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List of parties to the Biological Weapons Convention Several countries made reservations when ratifying the agreement declaring that it did not imply their complete satisfaction that the Treaty allows the stockpiling of biological agents and toxins for "prophylactic, protective or other peaceful purposes", nor should it imply recognition of other countries they do not recognise. According to a Report to the Meeting of States Parties to the Convention, as of August 2019 183 states have ratified the BWC. However, the status of the succession of a number of additional states to the BWC is unclear. For further details, see the Succession of colonies to the BWC section below. Multiple dates indicate the different days in which states submitted their signature or deposition, varied by location. This location is noted by: (L) for London, (M) for Moscow, and (W) for Washington D.C. The Republic of China (Taiwan), which is currently only recognized by , deposited their instruments of ratification of the BWC with the United States government prior to the US's decision to switch their recognition of the sole legitimate government of China from the Republic of China (ROC) to the People's Republic of China (PRC) in 1971. When the PRC subsequently ratified the treaty, they described the ROC's ratification as "illegal". The ROC has committed itself to continue to adhere to the requirements of the treaty, and the United States has declared that they still consider them to be "bound by its obligations". The following four states have signed, but not ratified the BWC | Biology | https://en.wikipedia.org/wiki?curid=18638946 | List of parties to the Biological Weapons Convention | 140,163 |
List of parties to the Biological Weapons Convention The following 10 UN member states have neither signed nor ratified the BWC. The status of several former dependent territories of a state party to the BWC, whose administrating power ratified the Convention on their behalf, with regards to the Convention following their independence is currently unclear. According to the Vienna Convention on Succession of States in respect of Treaties (to which 22 states are party), "newly independent states" (a euphemism for former colonies) receive a "clean slate", such that the new state does not inherit the treaty obligations of the colonial power, but that they may join multilateral treaties to which their former colonizers were a party without the consent of the other parties in most circumstances. Conversely, in "cases of separation of parts of a state" (a euphemism for all other new states), the new state remains bound by the treaty obligations of the state from which they separated. To date, this Convention has only been ratified by 22 states. The United Kingdom attached a territorial declaration to their instrument of ratification of the BWC in 1975 stating in part that it applied to: This declaration bound the territories of Kiribati and Tuvalu to the terms of the Convention. Following their independence, none of these states have made unambiguous declarations of succession to the BWC. Dominica and Vanuatu's statuses were likewise ambiguous from their independence until 2016 | Biology | https://en.wikipedia.org/wiki?curid=18638946 | List of parties to the Biological Weapons Convention | 140,164 |
List of parties to the Biological Weapons Convention In 1979, Kiribati gained their independence and subsequently the President of Kiribati sent a note to the UNSG stating that: Since then, none of the depositaries for the BWC have received an instrument of accession or succession to the Convention from Kiribati. However, the Government of Kiribati has made statements suggesting that it does not consider itself a party to the treaty. Following independence in 1978, the Prime Minister of Tuvalu sent a note to the UNSC stating that: Since then, none of the depositaries for the BWC have received an instrument of accession or succession to the Convention from Tuvalu. However, the Government of Tuvalu has made statements suggesting that it does not consider itself a party to the treaty. After becoming independent in 1978, the Prime Minister of Dominica sent a note to the Secretary-General of the United Nations (UNSG) stating that: The Government of Dominica later stated that it did not consider itself bound by the Convention. However, Dominica was listed as a state party to the BWC in documents from the Meetings of the States Parties to the BWC. The UK Treaty Office (as depositary) did not receive an instrument of succession from Dominica until 2016. In 1980, the territory gained their independence | Biology | https://en.wikipedia.org/wiki?curid=18638946 | List of parties to the Biological Weapons Convention | 140,165 |
List of parties to the Biological Weapons Convention Vanuatu was listed as a state party to the BWC in documents from the Meetings of the States Parties to the BWC, however the Government of Vanuatu made statements suggesting that it did not consider itself a party to the treaty and the UK depositary had no record of receiving an instrument of succession to the BWC from Vanuatu until 2016. | Biology | https://en.wikipedia.org/wiki?curid=18638946 | List of parties to the Biological Weapons Convention | 140,166 |
International Journal of Biometeorology The is a peer-reviewed scientific journal which publishes original research papers, review articles, and short communications on studies examining the interactions between living organisms and factors of the natural and artificial physical environment. The journal is published by Springer Science+Business Media on behalf of the International Society of Biometeorology, its scope includes the fields of Earth and environmental science, life sciences, animal physiology, plant physiology and environmental medicine/environmental psychology. | Biology | https://en.wikipedia.org/wiki?curid=18646738 | International Journal of Biometeorology | 140,167 |
List of sequenced plastomes A plastome is the genome of a plastid, a type of organelle found in plants and in a variety of protoctists. The number of known plastid genome sequences grew rapidly in the first decade of the twenty-first century. For example, 25 chloroplast genomes were sequenced for one molecular phylogenetic study. The flowering plants are especially well represented in complete chloroplast genomes. As of January, 2017, all of their orders are represented except Commelinales, Picramniales, Huerteales, Escalloniales, Bruniales, and Paracryphiales. A compilation of all available complete plastid genomes is maintained by the NCBI in a public repository. This sortable table is expected to compile complete plastid genomes representing the largest range of sizes, number of genes, and angiosperm families. Meta-algae are organisms with photosynthetic organelles of secondary or tertiary endosymbiotic origin, and their close non-photosynthetic, plastid-bearing, relatives. Apicomplexans are a secondarily non-photosynthetic group of chromalveoates which retain a reduced plastid organelle. Dinoflagellate plastid genomes are not organised into a single circular DNA molecule like other plastid genomes, but into an array of mini-circles. In some photosynthetic organisms that ability was acquired via symbiosis with a unicellular green alga (chlorophyte) or red alga (rhodophyte). In some such cases not only does the chloroplast of the former unicellular alga retain its own genome, but a remnant of the alga is also retained | Biology | https://en.wikipedia.org/wiki?curid=18667488 | List of sequenced plastomes | 140,168 |
List of sequenced plastomes When this retains a nucleus and a nuclear genome it is termed a nucleomorph. The unicellular eukaryote "Paulinella chromatophora" possesses an organelle (the cyanelle) which represents an independent case of the acquisition of photosynthesis by cyanobacterial endosymbiosis. (Note: the term cyanelle is also applied to the plastids of glaucophytes.) | Biology | https://en.wikipedia.org/wiki?curid=18667488 | List of sequenced plastomes | 140,169 |
Malnutrition–inflammation complex (syndrome), abbreviated as "MICS" and also known as "malnutrition–inflammation–cachexia syndrome", is a common condition in chronic disease states such as chronic kidney disease (where it is also known as uremic malnutrition or protein–energy malnutrition) and chronic heart failure. The MICS is believed to be a cause of survival paradoxes seen in these distinct patient populations, also known as reverse epidemiology populations. | Biology | https://en.wikipedia.org/wiki?curid=18675046 | Malnutrition–inflammation complex | 140,170 |
Kim Sterelny (born 1950) is an Australian philosopher and professor of philosophy in the Research School of Social Sciences at Australian National University and Victoria University of Wellington. He is the winner of several international prizes in the philosophy of science, and was previously editor of "Biology and Philosophy". He is also a member of the Australian Academy of the Humanities. He is currently the First Vice President of the Division for Logic, Methodology and Philosophy of Science and Technology of the International Union of History and Philosophy of Science and Technology (2020-2023). Sterelny's principal area of research is in the philosophy of biology. He states "the development of evolutionary biology since 1858 is one of the great intellectual achievements of science." Sterelny has also written extensively about the philosophy of psychology. He is the author of many important papers in these areas, including widely anthologised papers on group selection, meme theory and cultural evolution such as "Return of the Gene" (with Philip Kitcher), "Memes Revisited" and "The Evolution and Evolvability of Culture." Together with his former student Paul Griffiths, in 1999, Sterelny published "Sex and Death", a comprehensive treatment of problems and alternative positions in the philosophy of biology. This book incorporated a number of the positions developed in previous articles on the range of topics in the philosophy of biology | Biology | https://en.wikipedia.org/wiki?curid=18675139 | Kim Sterelny | 140,171 |
Kim Sterelny At certain points Sterelny and his coauthor differed (for example, on the Darwinian treatment of emotions and on the prospects for developmental systems theory). In 2004 Sterelny's book "Thought in a Hostile World: The Evolution of Human Cognition" received the Lakatos Award for a distinguished contribution to the philosophy of science. This book provides a Darwinian account of the nature and evolution of human cognitive capacities, and is an important alternative to nativist accounts familiar from evolutionary psychology. By combining an account of neural plasticity, group selection, and niche construction, Sterelny shows how much of the data on which nativist accounts rely can be accounted for without attributing a large number of genetically hardwired modules to the mind/brain. In 2008 Sterelny was awarded the Jean-Nicod Prize. His lectures are published under the title, "The Evolved Apprentice". These lectures build on the non-nativist Darwinian approach of "Thought in a Hostile World," while providing a discussion of a great deal of recent work by other philosophers, biological anthropologists and ecologists, gene-culture co-evolution theorists, and evolutionary game theorists. | Biology | https://en.wikipedia.org/wiki?curid=18675139 | Kim Sterelny | 140,172 |
Paul Breslin is a geneticist and biologist. He is most notable for his work in taste perception and oral irritation, in humans as well as in "Drosophila melanogaster", the common fruit fly. He is a member of the faculty at the Monell Chemical Senses Center and acts as director of the Science Apprenticeship Program. He is a professor in the Department of Nutritional Sciences at Rutgers, the State University of New Jersey. | Biology | https://en.wikipedia.org/wiki?curid=18682025 | Paul Breslin | 140,173 |
Science, Evolution, and Creationism is a publication by the United States National Academy of Sciences. The book's authors intended to provide a current and comprehensive explanation of evolution and "its importance in the science classroom". It was "intended for use by scientists, teachers, parents, and school board members who wanted to engage in more constructive conversations with others who remain uncertain about evolution and its place in the public school curriculum." The book, published on January 3, 2008, is available as a free PDF file on the National Academies Press website. "Science, Evolution, and Creationism" differs from prior National Academy of Sciences publications regarding creation and evolution in public education and the creation-evolution controversy; it is intended "specifically for the lay public", devoting much of its space to "explaining the differences between science and religion, and asserting that acceptance of evolution does not require abandoning belief in God." The book provides statements from notable biologists and clergy members to support the claim that "attempts to pit science and religion against each other create controversy where none needs to exist." The authors of "Science, Evolution, and Creationism", who include Francisco J | Biology | https://en.wikipedia.org/wiki?curid=18683754 | Science, Evolution, and Creationism | 140,174 |
Science, Evolution, and Creationism Ayala and Bruce Alberts, highlight developments in evolutionary biology and its relevance to the study of emerging infectious diseases, the 2006 discovery of the transitional fossil "Tiktaalik", and the application of evolutionary theory in many areas of science and engineering beyond biology. The book was released as several states, particularly Texas and Florida, considered revisions in state science standards. A study at Arizona State University used the book as part of a two-week module, within an introductory biology course, focusing on science, evolution, and religion. The percentage of students who held the view that there was a conflict between religion and evolution was reduced by about half. The pro-intelligent design organization, the Discovery Institute, states that "Science, Evolution, and Creationism" "completely misrepresent[s] intelligent design" and "exaggerates the success of evolution". Tony Perkins, president of the Family Research Council, argues that "Science, Evolution, and Creationism" "ignores" criticism of "Darwinism". In an interview on NBC, Glenn Branch, deputy director of the National Center for Science Education, called the publication "a definitive statement from a leading scientific authority about the scientific bankruptcy of intelligent design creationism." Praise for the publication was received from Lawrence Krauss and editorials in "Nature", "New Scientist", and several newspapers. | Biology | https://en.wikipedia.org/wiki?curid=18683754 | Science, Evolution, and Creationism | 140,175 |
End-Botomian mass extinction The end-Botomian mass extinction event, also known as the late early Cambrian extinctions, refer to two extinction intervals that occurred during Stages 4 and 5 of the Cambrian Period, approximately 513 to 509 million years ago. Estimates for the decline in global diversity over these events range from 50% of marine genera up to 80%. Among the organisms affected by this event were the small shelly fossils, archaeocyathids (an extinct group of sponges), trilobites, brachiopods, hyoliths, and mollusks . There are several hypotheses for the causes of these extinctions. There is evidence that major changes in the carbon cycle and sea level occurred during this time . Evidence also exists for the development of anoxia (a loss of oxygen) in some environments in the oceans . One hypothesis that unifies this evidence links these environmental changes to widespread volcanic eruptions caused by the emplacement of the Kalkarindji Large Igneous Province or LIP . These widespread eruptions would have injected large amounts of greenhouse gases into the atmosphere causing warming of the climate and subsequent acidification and loss of oxygen in the oceans . However the precise timing between the eruptions and the extinction events remain unresolved . | Biology | https://en.wikipedia.org/wiki?curid=18687743 | End-Botomian mass extinction | 140,176 |
Ranunculetum fluitantis is one of the 24 Aquatic plant communities (A18) included in the British National Vegetation Classification (NVC). The vegetation type or community comprises stands of submerged vegetation dominated by clumps of River water crowfoot. Few other plants are found with any frequency among the denser stands but there can be "Myriophyllum"; "Potamogeton perfoliatus" and patches of moss on submerged stones. | Biology | https://en.wikipedia.org/wiki?curid=18689064 | Ranunculetum fluitantis | 140,177 |
Oophila amblystomatis, commonly known as chlamydomonad algae or salamander algae, is a species of single-celled green algae. The Latin specific name means "loves salamander eggs". It does not occur anywhere in nature other than in the eggs of the spotted salamander, "Ambystoma maculatum". The alga can invade and grow in the amphibian's egg capsule. Once inside, it metabolizes the carbon dioxide produced by the embryo and provides it with oxygen as a result of photosynthesis. This is an example of symbiosis, and the only known example an intracellular endosymbiont microbe in vertebrates. This symbiosis between "Oophila" and the salamander may exist beyond the oocyte and early embryonic stage. Chlorophyll autofluorescence observation and ribosomal DNA analysis suggest that this algal species has invaded embryonic salamander tissues and cells during development and may even be transmitted to the next generation. "amblystomatis" are only found in freshwater in woodland ponds. They grow best at a water depth of 30cm with the water temperature being 15C and an air temperature of 14C. Their optimal pH tolerance ranges from 6.26-6.46 and they require an environment where there is 12 hours of sunlight and 12 hours of darkness. Cells are motile are able to move the water by the use of a flagelluma. "amblystomatis" can also reproduce sexually and asexually. 16S rRNA has been partially sequenced as well as the 18S rRNA for the plasmid, however whole genome sequencing has not been done. | Biology | https://en.wikipedia.org/wiki?curid=18692111 | Oophila | 140,178 |
Pycnidium A pycnidium (plural pycnidia) is an asexual fruiting body produced by mitosporic fungi in the form order Sphaeropsidales (Deuteromycota, Coelomycetes). It is often spherical or inversely pearshaped (obpyriform) and its internal cavity is lined with conidiophores. When ripe, an opening generally appears at the top, through which the pycnidiospores escape. | Biology | https://en.wikipedia.org/wiki?curid=18692252 | Pycnidium | 140,179 |
Acervulus An acervulus (pl. acervuli) is a small asexual fruiting body that erupts through the epidermis of host plants parasitised by mitosporic fungi of the form order Melanconiales (Deuteromycota, Coelomycetes). It has the form of a small cushion at the bottom of which short crowded conidiophores are formed. The spores escape through an opening at the top. | Biology | https://en.wikipedia.org/wiki?curid=18692328 | Acervulus | 140,180 |
Sporodochium A sporodochium (pl. sporodochia) is a small, compact stroma (mass of hyphae) usually formed on host plants parasitised by mitosporic fungi of the form order Tuberculariales (subdivision Deuteromycota, class Hyphomycetes). This stroma bears the conidiophores on which the asexual spores or conidia are formed. | Biology | https://en.wikipedia.org/wiki?curid=18692401 | Sporodochium | 140,181 |
Seraticin is an antibiotic discovered by scientists at Swansea University able to inhibit 12 different strains of methicillin-resistant "Staphylococcus aureus" (MRSA), as well as "E. coli" and "C. difficile". The research was funded by the charity Action Medical Research, with support from the Rosetrees Trust. was isolated as a compound of less than 500 Da molecular weight from the maggot secretions of the common green bottle fly ("Lucilia sericata"). It was patented in 2010 and has the empirical formula , but its chemical identity is unknown. | Biology | https://en.wikipedia.org/wiki?curid=18733028 | Seraticin | 140,182 |
Kunio Yamazaki Dr. was a biologist who worked at the Monell Chemical Senses Center from 1980 until his death. Yamazaki is most notable for his extensive work with the major histocompatibility complex. He has worked with Dr. Gary Beauchamp, also of Monell, before. | Biology | https://en.wikipedia.org/wiki?curid=18733535 | Kunio Yamazaki | 140,183 |
Chromosome landing Chromosomal landing is a genetic technique used to identify and isolate clones in a genetic library. Chromosomal landing reduces the problem of analyzing large, and/or highly repetitive genomes by minimizing the need for chromosome walking. It is based on the principle that the expected average between-marker distances can be smaller than the average insert length of a clone library containing the gene of interest. From the abstract of : | Biology | https://en.wikipedia.org/wiki?curid=18744044 | Chromosome landing | 140,184 |
Johan Lundström Dr. Johan N. Lundström (born 1973) is a Swedish biologist and psychologist. He was awarded his Ph.D. in 2005 from Uppsala University and is most notable for his chemosensory work, and currently works at the Monell Chemical Senses Center. His experiments involve the use of neuroimaging and testing of human behavior. | Biology | https://en.wikipedia.org/wiki?curid=18744801 | Johan Lundström | 140,185 |
History of attachment theory Attachment theory, originating in the work of John Bowlby, is a psychological, evolutionary and ethological theory that provides a descriptive and explanatory framework for understanding interpersonal relationships between human beings. In order to formulate a comprehensive theory of the nature of early attachments, Bowlby explored a range of fields including evolution by natural selection, object relations theory (psychoanalysis), control systems theory, evolutionary biology and the fields of ethology and cognitive psychology. There were some preliminary papers from 1958 onwards but the full theory is published in the trilogy "Attachment and Loss", 1969- 82. Although in the early days Bowlby was criticised by academic psychologists and ostracised by the psychoanalytic community, attachment theory has become the dominant approach to understanding early social development and given rise to a great surge of empirical research into the formation of children's close relationships. In infants, behavior associated with attachment is primarily a process of proximity seeking to an identified attachment figure in situations of perceived distress or alarm, for the purpose of survival. Infants become attached to adults who are sensitive and responsive in social interactions with the infant, and who remain as consistent caregivers for some months during the period from about six months to two years of age | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,186 |
History of attachment theory During the later part of this period, children begin to use attachment figures (familiar people) as a "secure base" to explore from and return to. Parental responses lead to the development of patterns of attachment which in turn lead to 'internal working models' which will guide the individual's feelings, thoughts, and expectations in later relationships.<ref name="Bretherton/Mul"></ref> Separation anxiety or grief following serious loss are normal and natural responses in an attached infant. The human infant is considered by attachment theorists to have a need for a secure relationship with adult caregivers, without which normal social and emotional development will not occur. However, different relationship experiences can lead to different developmental outcomes. Mary Ainsworth developed a theory of a number of attachment patterns or "styles" in infants in which distinct characteristics were identified; these were secure attachment, avoidant attachment, anxious attachment and, later, disorganized attachment. In addition to care-seeking by children, peer relationships of all ages, romantic and sexual attraction, and responses to the care needs of infants or sick or elderly adults may be construed as including some components of attachment behavior. A theory of attachment is a framework of ideas that attempt to explain attachment, the almost universal human tendency to prefer certain familiar companions over other people, especially when ill, injured, or distressed | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,187 |
History of attachment theory Historically, certain social preferences, like those of parents for their children, were explained by reference to instinct, or the moral worth of the individual. The concept of infants' emotional attachment to caregivers has been known anecdotally for hundreds of years. Most early observers focused on the anxiety displayed by infants and toddlers when threatened with separation from a familiar caregiver. Psychological theories about attachment were suggested from the late nineteenth century onward. Freudian theory attempted a systematic consideration of infant attachment and attributed the infant's attempts to stay near the familiar person to motivation learned through feeding experiences and gratification of libidinal drives. In the 1930s, the British developmentalist Ian Suttie put forward the suggestion that the child's need for affection was a primary one, not based on hunger or other physical gratifications. A third theory prevalent at the time of Bowlby's development of attachment theory was "dependency". This approach posited that infants were dependent on adult caregivers but that dependency was, or should be outgrown as the individual matured. Such an approach perceived attachment behaviour in older children as regressive whereas within attachment theory older children and adults remain attached and indeed a secure attachment is associated with independent exploratory behaviour rather than dependence | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,188 |
History of attachment theory William Blatz, a Canadian psychologist and teacher of Bowlby's colleague Mary Ainsworth, was among the first to stress the need for security as a normal part of personality at all ages, as well as normality of the use of others as a secure base and the importance of social relationships for other aspects of development. Current attachment theory focuses on social experiences in early childhood as the source of attachment in childhood and in later life. Attachment theory was developed by Bowlby as a consequence of his dissatisfaction with existing theories of early relationships. Bowlby was influenced by the beginnings of the object relations school of psychoanalysis and in particular, Melanie Klein, although he profoundly disagreed with the psychoanalytic belief then prevalent that saw infants' responses as relating to their internal fantasy life rather than to real life events. As Bowlby began to formulate his concept of attachment, he was influenced by case studies by Levy, Powdermaker, Lowrey, Bender and Goldfarb. An example is the one by David Levy that associated an adopted child's lack of social emotion to her early emotional deprivation. Bowlby himself was interested in the role played in delinquency by poor early relationships, and explored this in a study of young thieves. Bowlby's contemporary René Spitz proposed that "psychotoxic" results were brought about by inappropriate experiences of early care | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,189 |
History of attachment theory A strong influence was the work of James and Joyce Robertson who filmed the effects of separation on children in hospital. They and Bowlby collaborated in making the 1952 documentary film "A Two-Year Old Goes to the Hospital" illustrating the impact of loss and suffering experienced by young children separated from their primary caretakers. This film was instrumental in a campaign to alter hospital restrictions on visiting by parents. In his 1951 monograph for the World Health Organization, "Maternal Care and Mental Health", Bowlby put forward the hypothesis that "the infant and young child should experience a warm, intimate, and continuous relationship with his mother (or permanent mother substitute) in which both find satisfaction and enjoyment" and that not to do so may have significant and irreversible mental health consequences. This proposition was both influential in terms of the effect on the institutional care of children, and highly controversial. There was limited empirical data at the time and no comprehensive theory to account for such a conclusion. Following the publication of "Maternal Care and Mental Health", Bowlby sought new understanding from such fields as evolutionary biology, ethology, developmental psychology, cognitive science and control systems theory and drew upon them to formulate the innovative proposition that the mechanisms underlying an infants tie emerged as a result of evolutionary pressure | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,190 |
History of attachment theory He realised that he had to develop a new theory of motivation and behaviour control, built on up-to-date science rather than the outdated psychic energy model espoused by Freud. Bowlby expressed himself as having made good the "deficiencies of the data and the lack of theory to link alleged cause and effect" in "Maternal Care and Mental Health" in his later work "Attachment and Loss" published between 1969 and 1980. Bowlby's first official representations were carried out for the relationship theory in three very controversial lectures in 1957 by the British Psychoanalytical Society in London. The formal origin of attachment theory can be traced to the publication of two 1958 papers, one being Bowlby's "The Nature of the Child's Tie to his Mother", in which the precursory concepts of "attachment" were introduced, and Harry Harlow's "The Nature of Love", based on the results of experiments which showed, approximately, that infant rhesus monkeys spent more time with soft mother-like dummies that offered no food than they did with dummies that provided a food source but were less pleasant to the touch. Bowlby followed this up with two more papers, "Separation Anxiety" (1960a), and "Grief and Mourning in Infancy and Early Childhood" (1960b). At about the same time, Bowlby's former colleague, Mary Ainsworth was completing extensive observational studies on the nature of infant attachments in Uganda with Bowlby's ethological theories in mind | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,191 |
History of attachment theory Mary Ainsworth's innovative methodology and comprehensive observational studies informed much of the theory, expanded its concepts and enabled some of its tenets to be empirically tested. Attachment theory was finally presented in 1969 in "Attachment" the first volume of the "Attachment and Loss" trilogy. The second and third volumes, "Separation: Anxiety and Anger" and "Loss: Sadness and Depression" followed in 1972 and 1980 respectively. "Attachment" was revised in 1982 to incorporate more recent research. Bowlby's attention was first drawn to ethology when he read Lorenz's 1952 publication in draft form although Lorenz had published much earlier work. Soon after this he encountered the work of Tinbergen, and began to collaborate with Robert Hinde. In 1953 he stated "the time is ripe for a unification of psychoanalytic concepts with those of ethology, and to pursue the rich vein of research which this union suggests". Konrad Lorenz had examined the phenomenon of "imprinting" and felt that it might have some parallels to human attachment. Imprinting, a behavior characteristic of some birds and a very few mammals, involves rapid learning of recognition by a young bird or animal exposed to a conspecific or an object or organism that behaves suitably. The learning is possible only within a limited age period, known as a critical period | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,192 |
History of attachment theory This rapid learning and development of familiarity with an animate or inanimate object is accompanied by a tendency to stay close to the object and to follow when it moves; the young creature is said to have been imprinted on the object when this occurs. As the imprinted bird or animal reaches reproductive maturity, its courtship behavior is directed toward objects that resemble the imprinting object. Bowlby's attachment concepts later included the ideas that attachment involves learning from experience during a limited age period, and that the learning that occurs during that time influences adult behavior. However, he did not apply the imprinting concept in its entirety to human attachment, nor assume that human development was as simple as that of birds. He did, however, consider that attachment behavior was best explained as instinctive in nature, an approach that does not rule out the effect of experience, but that stresses the readiness the young child brings to social interactions. Some of Lorenz's work had been done years before Bowlby formulated his ideas, and indeed some ideas characteristic of ethology were already discussed among psychoanalysts some time before the presentation of attachment theory. Bowlby's view of attachment was also influenced by psychoanalytical concepts and the earlier work of psychoanalysts. In particular he was influenced by observations of young children separated from familiar caregivers, as provided during World War II by Anna Freud and her colleague Dorothy Burlingham | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,193 |
History of attachment theory Observations of separated children's grief by René Spitz were another important factor in the development of attachment theory. However, Bowlby rejected psychoanalytical explanations for early infant bonds. He rejected both Freudian "drive-theory", which he called the Cupboard Love theory of relationships, and early object-relations theory as both in his view failed to see the attachment as a psychological bond in its own right rather than an instinct derived from feeding or sexuality. Thinking in terms of primary attachment and neo-darwinism, Bowlby identified as what he saw as fundamental flaws in psychoanalysis, namely the overemphasis of internal dangers at the expense of external threat, and the picture of the development of personality via linear "phases" with "regression" to fixed points accounting for psychological illness. Instead he posited that several lines of development were possible, the outcome of which depended on the interaction between the organism and the environment. In attachment this would mean that although a developing child has a propensity to form attachments, the nature of those attachments depends on the environment to which the child is exposed. The important concept of the internal working model of social relationships was adopted by Bowlby from the work of the philosopher Kenneth Craik, who had noted the adaptiveness of the ability of thought to predict events, and stressed the survival value of and natural selection for this ability | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,194 |
History of attachment theory According to Craik, prediction occurs when a "small-scale model" consisting of brain events is used to represent not only the external environment, but the individual's own possible actions. This model allows a person to mentally try out alternatives and to use knowledge of the past in responding to the present and future. At about the same time that Bowlby was applying Craik's ideas to the study of attachment, other psychologists were using these concepts in discussion of adult perception and cognition. The theory of control systems (cybernetics), developing during the 1930s and '40s, influenced Bowlby's thinking. The young child's need for proximity to the attachment figure was seen as balancing homeostatically with the need for exploration. The actual distance maintained would be greater or less as the balance of needs changed; for example, the approach of a stranger, or an injury, would cause the child to seek proximity when a moment before he had been exploring at a distance. Behaviour analysts have constructed models of attachment. Such models are based on the importance of contingent relationships. Behaviour analytic models have received support from research. and meta-analytic reviews. Although research on attachment behaviors continued after Bowlby's death in 1990, there was a period of time when attachment theory was considered to have run its course | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,195 |
History of attachment theory Some authors argued that attachment should not be seen as a trait (lasting characteristic of the individual), but instead should be regarded as an organizing principle with varying behaviors resulting from contextual factors. Related later research looked at cross-cultural differences in attachment, and concluded that there should be re-evaluation of the assumption that attachment is expressed identically in all humans. In a recent study conducted in Sapporo, Behrens, et al., 2007 found attachment distributions consistent with global norms using the six-year Main & Cassidy scoring system for attachment classification. Interest in attachment theory continued, and the theory was later extended to adult romantic relationships by Cindy Hazan and Phillip Shaver. Peter Fonagy and Mary Target have attempted to bring attachment theory and psychoanalysis into a closer relationship by way of such aspects of cognitive science as mentalization, the ability to estimate what the beliefs or intentions of another person may be. A "natural experiment" has permitted extensive study of attachment issues, as researchers have followed the thousands of Romanian orphans who were adopted into Western families after the end of Nicolae Ceauşescu's regime. The English and Romanian Adoptees Study Team, led by Michael Rutter, has followed some of the children into their teens, attempting to unravel the effects of poor attachment, adoption and new relationships, and the physical and medical problems associated with their early lives | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,196 |
History of attachment theory Studies on the Romanian adoptees, whose initial conditions were shocking, have in fact yielded reason for optimism. Many of the children have developed quite well, and the researchers have noted that separation from familiar people is only one of many factors that help to determine the quality of development. Neuroscientific studies are examining the physiological underpinnings of observable attachment style, such as vagal tone which influences capacities for intimacy, stress response which influences threat reactivity (Lupien, McEwan, Gunnar & Heim, 2009), as well as neuroendocrinology such as oxytocin. These types of studies underscore the fact that attachment is an embodied capacity not only a cognitive one. Some authors have noted the connection of attachment theory with Western family and child care patterns characteristic of Bowlby's time. The implication of this connection is that attachment-related experiences (and perhaps attachment itself) may alter as young children's experience of care change historically. For example, changes in attitudes toward female sexuality have greatly increased the numbers of children living with their never-married mothers and being cared for outside the home while the mothers work. This social change, in addition to increasing abortion rates, has also made it more difficult for childless people to adopt infants in their own countries, and has increased the number of older-child adoptions and adoptions from third-world sources | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,197 |
History of attachment theory Adoptions and births to same-sex couples have increased in number and even gained some legal protection, compared to their status in Bowlby's time. One focus of attachment research has been on the difficulties of children whose attachment history was poor, including those with extensive non-parental child care experiences. Concern with the effects of child care was intense during the so-called "day care wars" of the late 20th century, during which the deleterious effects of day care were stressed. As a beneficial result of this controversy, training of child care professionals has come to stress attachment issues and the need for relationship-building through techniques such as assignment of a child to a specific care provider. Although only high-quality child care settings are likely to follow through on these considerations, nevertheless a larger number of infants in child care receive attachment-friendly care than was the case in the past, and emotional development of children in nonparental care may be different today than it was in the 1980s or in Bowlby's time. Finally, any critique of attachment theory needs to consider how the theory has connected with changes in other psychological theories. Research on attachment issues has begun to include concepts related to behaviour genetics and to the study of temperament (constitutional factors in personality), but it is unusual for popular presentations of attachment theory to include these | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,198 |
History of attachment theory Importantly, some researchers and theorists have begun to connect attachment with the study of mentalization or Theory of Mind, the capacity that allows human beings to guess with some accuracy what thoughts, emotions, and intentions lie behind behaviours as subtle as facial expression or eye movement. The connection of theory of mind with the internal working model of social relationships may open a new area of study and lead to alterations in attachment theory. The maternal deprivation hypothesis, attachment theory's precursor, was enormously controversial. Ten years after the publication of the hypothesis, Ainsworth listed nine concerns that she felt were the chief points of controversy. Ainsworth separated the three dimensions of maternal deprivation into lack of maternal care, distortion of maternal care and discontinuity of maternal care. She analysed the dozens of studies undertaken in the field and concluded that the basic assertions of the maternal deprivation hypothesis were sound although the controversy continued. As the formulation of attachment theory progressed, critics commented on empirical support for the theory and for the possible alternative explanations for results of empirical research. Wootton questioned the suggestion that early attachment history (as it would now be called) had a lifelong impact | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,199 |
History of attachment theory In 1957 found the young relationship theory in the DDR (East Germany) by an essay of James Robertson in the "Zeitschrift für ärztliche Fortbildung" (magazine for a medical further education) and Eva Schmidt-Kolmer carried out some journal extracts from Bowlby's essay "Maternal Care and mental Health" for WHO. In the following period it came to extensive comparative development psychological in the DDR at the end of the fifties. Examinations between family-bound babies and small children, day and week hayracks-as well as Institution children. The findings could do with regard to the morbidity for the family-bound children, the physical and emotional development as well as adaption disturbances at change of environment. After the construction of the Berlin Wall 1961 it didn't come to any additional publications in the DDR Relationship theory and comparative investigations with family-bound children. The previous ones Research results weren't published further and got like the relationship theory into oblivion in the DDR in the subsequent years. In the 1970s, problems with the emphasis on attachment as a trait (a stable characteristic of an individual) rather than as a type of behaviour with important organising functions and outcomes, led some authors to consider that "attachment (as implying anything but infant-adult interaction) [may be said to have] outlived its usefulness as a developmental construct..." and that attachment behaviours were best understood in terms of their functions in the child's life | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,200 |
History of attachment theory Children may achieve a given function, such as a sense of security, in many different ways and the various but functionally comparable behaviours should be categorized as related to each other. This way of thinking saw the secure base concept (the organisation of exploration of an unfamiliar situation around returns to a familiar person) as "central to the logic and coherence of attachment theory and to its status as an organizational construct." Similarly, Thompson pointed out that "other features of early parent-child relationships that develop concurrently with attachment security, including negotiating conflict and establishing cooperation, also must be considered in understanding the legacy of early attachments." From an early point in the development of attachment theory, there was criticism of the theory's lack of congruence with the various branches of psychoanalysis. Like other members of the British object-relations group, Bowlby rejected Melanie Klein's views that considered the infant to have certain mental capacities at birth and to continue to develop emotionally on the basis of fantasy rather than of real experiences. But Bowlby also withdrew from the object-relations approach (exemplified, for example, by Anna Freud), as he abandoned the "drive theory" assumptions in favor of a set of automatic, instinctual behaviour systems that included attachment. Bowlby's decisions left him open to criticism from well-established thinkers working on problems similar to those he addressed | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,201 |
History of attachment theory Bowlby was effectively ostracized from the psychoanalytic community. More recently some psychoanalysts have sought to reconcile the two theories in the form of attachment-based psychotherapy, a therapeutic approach. Ethologists expressed concern about the adequacy of some of the research on which attachment theory was based, particularly the generalisation to humans from animal studies. Schur, discussing Bowlby's use of ethological concepts (pre-1960) commented that these concepts as used in attachment theory had not kept up with changes in ethology itself. Ethologists and others writing in the 1960s and 1970s questioned the types of behaviour used as indications of attachment, and offered alternative approaches. For example, crying on separation from a familiar person was suggested as an index of attachment. Observational studies of young children in natural settings also provided behaviours that might be considered to indicate attachment; for example, staying within a predictable distance of the mother without effort on her part and picking up small objects and bringing them to the mother, but usually not other adults. Although ethological work tended to be in agreement with Bowlby, work like that just described led to the conclusion that "[w]e appear to disagree with Bowlby and Ainsworth on some of the details of the child's interactions with its mother and other people" | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,202 |
History of attachment theory Some ethologists pressed for further observational data, arguing that psychologists "are still writing as if there is a real entity which is 'attachment', existing over and above the observable measures." Robert Hinde expressed concern with the use of the word "attachment" to imply that it was an intervening variable or a hypothesised internal mechanism rather than a data term. He suggested that confusion about the meaning of attachment theory terms "could lead to the 'instinct fallacy' of postulating a mechanism with the behaviours, and then using that as an explanation for the behaviour". However, Hinde considered "attachment behaviour system" to be an appropriate term of theory language which did not offer the same problems "because it refers to postulated control systems that determine the relations between different kinds of behaviour." Bowlby's reliance on Piaget's theory of cognitive development gave rise to questions about object permanence (the ability to remember an object that is temporarily absent) and its connection to early attachment behaviours, and about the fact that the infant's ability to discriminate strangers and react to the mother's absence seems to occur some months earlier than Piaget suggested would be cognitively possible. More recently, it has been noted that the understanding of mental representation has advanced so much since Bowlby's day that present views can be far more specific than those of Bowlby's time | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,203 |
History of attachment theory In 1969, Gewirtz discussed how mother and child could provide each other with positive reinforcement experiences through their mutual attention and therefore learn to stay close together; this explanation would make it unnecessary to posit innate human characteristics fostering attachment. Learning theory saw attachment as a remnant of dependency and the quality of attachment as merely a response to the caregivers cues. Behaviourists saw behaviours such as crying as a random activity that meant nothing until reinforced by a caregivers response therefore frequent responses would result in more crying. To attachment theorists, crying is an inborn attachment behaviour to which the caregiver must respond if the infant is to develop emotional security. Conscientious responses produce security which enhances autonomy and results in less crying. Ainsworth's research in Baltimore supported the attachment theorists view. In the last decade, behaviour analysts have constructed models of attachment based on the importance of contingent relationships. These behaviour analytic models have received some support from research and meta-analytic reviews. There has been critical discussion of conclusions drawn from clinical and observational work, and whether or not they actually support tenets of attachment theory | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,204 |
History of attachment theory For example, Skuse based criticism of a basic tenet of attachment theory on the work of Anna Freud with children from Theresienstadt, who apparently developed relatively normally in spite of serious deprivation during their early years. This discussion concluded from Freud's case and from some other studies of extreme deprivation that there is an excellent prognosis for children with this background, unless there are biological or genetic risk factors. The psychoanalyst Margaret Mahler interpreted ambivalent or aggressive behaviour of toddlers toward their mothers as a normal part of development, not as evidence of poor attachment history. Some of Bowlby's interpretations of the data reported by James Robertson were eventually rejected by the researcher, who reported data from 13 young children who were cared for in ideal circumstances during separation from their mothers. Robertson noted, "...Bowlby acknowledges that he draws mainly upon James Robertson's institutional data. But in developing his grief and mourning theory, Bowlby, without adducing non-institutional data, has generalized Robertson's concept of protest, despair and denial beyond the context from which it was derived. He asserts that these are the usual responses of young children to separation from the mother regardless of circumstance.. | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,205 |
History of attachment theory "; however, of the 13 separated children who received good care, none showed protest and despair, but "coped with separation from the mother when cared for in conditions from which the adverse factors which complicate institutional studies were absent". In the second volume of the trilogy, "Separation", published two years later, Bowlby acknowledged that Robertsons foster study had caused him to modify his views on the traumatic consequences of separation in which insufficient weight was given to the influence of skilled care from a familiar substitute. Some authors have questioned the idea of attachment patterns, thought to be measured by techniques like the Strange Situation Protocol. Such techniques yield a taxonomy of categories considered to represent qualitative difference in attachment relationships (for example, secure attachment versus avoidant). However, a categorical model is not necessarily the best representation of individual difference in attachment. An examination of data from 1139 15-month-olds showed that variation was continuous rather than falling into natural groupings. This criticism introduces important questions for attachment typologies and the mechanisms behind apparent types, but in fact has relatively little relevance for attachment theory itself, which "neither requires nor predicts discrete patterns of attachment." As was noted above, ethologists have suggested other behavioural measures that may be of greater importance than Strange Situation behaviour | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,206 |
History of attachment theory Following the argument made in the 1970s that attachment should not be seen as a trait (lasting characteristic of the individual), but instead should be regarded as an organising principle with varying behaviours resulting from contextual factors, later research looked at cross-cultural differences in attachment, and concluded that there should be re-evaluation of the assumption that attachment is expressed identically in all humans. Various studies appeared to show cultural differences but a 2007 study conducted in Sapporo in Japan found attachment distributions consistent with global norms using the six-year Main & Cassidy scoring system for attachment classification. Recent critics such as J. R. Harris, Steven Pinker and Jerome Kagan are generally concerned with the concept of infant determinism (Nature versus nurture) and stress the possible effects of later experience on personality. Building on the earlier work on temperament of Stella Chess, Kagan rejected almost every assumption on which attachment theory etiology was based, arguing that heredity was far more important than the transient effects of early environment, for example a child with an inherent difficult temperament would not illicit sensitive behavioural responses from their care giver. The debate spawned considerable research and analysis of data from the growing number of longitudinal studies | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,207 |
History of attachment theory Subsequent research has not bourne out Kagan's argument and broadly demonstrates that it is the caregivers' behaviours that form the child's attachment style although how this style is expressed may differ with temperament. Harris and Pinker have put forward the notion that the influence of parents has been much exaggerated and that socialisation takes place primarily in peer groups, although H. Rudolph Schaffer concludes that parents and peers fulfill different functions and have distinctive roles in children's development. Concern about attachment theory has been raised with regard to the fact that infants often have multiple relationships, within the family as well as in child care settings, and that the dyadic model characteristic of attachment theory cannot address the complexity of real-life social experiences. | Biology | https://en.wikipedia.org/wiki?curid=18756845 | History of attachment theory | 140,208 |
Stem cell doping is the postulated practice of enhancing athletic performance through various beneficial effects of stem cells injected into the bloodstream or otherwise introduced into the body. Currently there are no documented cases of stem cell doping, but there are suspicions that the practice may already be emerging. | Biology | https://en.wikipedia.org/wiki?curid=18760780 | Stem cell doping | 140,209 |
Animal nutrition focuses on the dietary needs of animals, primarily those in agriculture and food production, but also in zoo's, aquariums, and wildlife management. There are seven major classes of nutrients: carbohydrates, fats, fibre, minerals, proteins, vitamins, and water. Macronutrients (excluding fiber and water) provide structural material (amino acids from which proteins are built, and lipids from which cell membranes and some signaling molecules are built) and energy. Some of the structural material can be used to generate energy internally, though the net energy depends on such factors as absorption and digestive effort, which vary substantially from instance to instance. Vitamins, minerals, fiber, and water do not provide energy, but are required for other reasons. A third class dietary material, fiber (i.e., non-digestible material such as cellulose), seems also to be required, for both mechanical and biochemical reasons, though the exact reasons remain unclear. Molecules of carbohydrates and fats consist of carbon, hydrogen, and oxygen atoms. Carbohydrates range from simple monosaccharides (glucose, fructose, galactose) to complex polysaccharides (starch). Fats are triglycerides, made of assorted fatty acid monomers bound to glycerol backbone. Some fatty acids, but not all, are essential in the diet: they cannot be synthesized in the body. Protein molecules contain nitrogen atoms in addition to carbon, oxygen, and hydrogen. The fundamental components of protein are nitrogen-containing amino acids | Biology | https://en.wikipedia.org/wiki?curid=18761393 | Animal nutrition | 140,210 |
Animal nutrition Essential amino acids cannot be made by the animal. Some of the amino acids are convertible (with the expenditure of energy) to glucose and can be used for energy production just as ordinary glucose. By breaking down existing protein, some glucose can be produced internally; the remaining amino acids are discarded, primarily as urea in urine. This occurs normally only during prolonged starvation. Other dietary substances found in plant foods (phytochemicals, polyphenols) are not identified as essential nutrients but appear to impact health in both positive and negative ways. Most foods contain a mix of some or all of the nutrient classes, together with other substances. Some nutrients can be stored internally (e.g., the fat soluble vitamins), while others are required more or less continuously. Poor health can be caused by a lack of required nutrients or, in extreme cases, too much of a required nutrient. For example, both salt provides sodium and chloride, both essential nutrients, but will cause illness or even death in too large amounts. Dietary fibre is a carbohydrate (polysaccharide or oligosaccharide) that is incompletely absorbed in some animals. Proteins are the basis of many animal body structures (e.g. muscles, skin, and hair). They also form the enzymes which control chemical reactions throughout the body. Each molecule is composed of amino acids which are characterized by the inclusion of nitrogen and sometimes sulfur | Biology | https://en.wikipedia.org/wiki?curid=18761393 | Animal nutrition | 140,211 |
Animal nutrition The body requires amino acids to produce new proteins (protein retention) and to replace damaged proteins (maintenance). As there is no protein or amino acid storage provision, amino acids must be present in the diet. Excess amino acids are discarded, typically in the urine. For all animals, some amino acids are "essential" (an animal cannot produce them internally) and some are "non-essential" (the animal can produce them from other nitrogen-containing compounds). A diet that contains adequate amounts of amino acids (especially those that are essential) is particularly important in some situations: during early development and maturation, pregnancy, lactation, or injury (a burn, for instance). A few amino acids from protein can be converted into glucose and used for fuel through a process called gluconeogenesis; this is done in quantity only during starvation. Dietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen that are present in nearly all organic molecules. The term "mineral" is archaic, since the intent is to describe simply the less common elements in the diet. Many elements are essential in relative quantity; they are usually called "bulk minerals". Some are structural, but many play a role as electrolytes. These include: Many elements are required in trace amounts, usually because they play a catalytic role in enzymes. Vitamin deficiencies may result in disease conditions | Biology | https://en.wikipedia.org/wiki?curid=18761393 | Animal nutrition | 140,212 |
Animal nutrition Excess of some vitamins is also dangerous to health (notably vitamin A), and animal nutrition researchers have managed to establish safe levels for some common companion animals. Deficiency or excess of minerals can also have serious health consequences. Though not a nutrient as such, an entry for "ash" is sometimes found on nutrition labels, especially for pet food. This entry measures the weight of inorganic material left over after the food is burned for two hours at 600 °C. Thus, it does not include water, fibre, and nutrients that provide calories, but it does include some nutrients, such as minerals Too much ash may contribute to feline urological syndrome in domestic cats. Animal intestines contain a large population of gut flora which are essential to digestion, and are also affected by the food eaten. | Biology | https://en.wikipedia.org/wiki?curid=18761393 | Animal nutrition | 140,213 |
Metallophyte A metallophyte is a plant that can tolerate high levels of heavy metals such as lead. Such plants range between "obligate metallophytes" (which can only survive in the presence of these metals), and "facultative metallophytes" which can tolerate such conditions but are not confined to them. European examples include alpine pennycress ("Thlaspi caerulescens"), the zinc violet ("Viola calaminaria"), spring sandwort ("Minuartia verna"), sea thrift ("Armeria maritima"), "Cochlearia", common bent ("Agrostis capillaris") and plantain ("Plantago lanceolata"). Few metallophytes are known from Latin America. Metallophytes commonly exist as specialised flora found on spoil heaps of mines. Such plants have potential for use for phytoremediation of contaminated ground. | Biology | https://en.wikipedia.org/wiki?curid=18765773 | Metallophyte | 140,214 |
Dancing plague of 1518 The dancing plague (or dance epidemic) of 1518 was a case of dancing mania that occurred in Strasbourg, Alsace (now modern-day France), in the Holy Roman Empire in July 1518. Somewhere between 50 and 400 people took to dancing for days. The outbreak began in July 1518 when a woman began to dance fervently in a street in Strasbourg. Some sources claim that, for a period, the plague killed around fifteen people per day; however, the sources of the city of Strasbourg at the time of the events did not mention the number of deaths, or even if there were fatalities. Historical documents, including "physician notes, cathedral sermons, local and regional chronicles, and even notes issued by the Strasbourg city council" are clear that the victims danced. It is not known why. Historical sources agree that there was an outbreak of dancing after a single woman started dancing, a group of mostly young women joined in, and the dancing did not seem to die down. It lasted for such a long time that it attracted the attention of the Strasbourg magistrate and bishop, and some number of doctors ultimately intervened, putting the afflicted in a hospital. Where the controversy arises is the matter of whether people ultimately danced to their deaths. The main source for this claim comes from John Waller, who has written several journal articles on the subject and the book "A Time to Dance, a Time to Die: The Extraordinary Story of the Dancing Plague of 1518" | Biology | https://en.wikipedia.org/wiki?curid=18776822 | Dancing plague of 1518 | 140,215 |
Dancing plague of 1518 There do not appear to be any sources contemporaneous to the events that make note of any fatalities. The sources cited by Waller that mention deaths were all from later retellings of the events. There is also uncertainty around the identity of the initial dancer (either an unnamed woman or "Frau Troffea") and the number of dancers involved (somewhere between 50 and 400). Modern theories include food-poisoning caused by the toxic and psychoactive chemical products of ergot fungi, which grows commonly on grains in the wheat family (such as rye) that was used for baking bread. Ergotamine is the main psychoactive product of ergot fungi; it is structurally related to the drug lysergic acid diethylamide (LSD-25), and is the substance from which LSD-25 was originally synthesized. The same fungus has also been implicated in other major historical anomalies, including the Salem witch trials. However, John Waller in "The Lancet" argues that "this theory does not seem tenable, since it is unlikely that those poisoned by ergot could have danced for days at a time. Nor would so many people have reacted to its psychotropic chemicals in the same way. The ergotism theory also fails to explain why virtually every outbreak occurred somewhere along the Rhine and Moselle rivers, areas linked by water but with quite different climates and crops" | Biology | https://en.wikipedia.org/wiki?curid=18776822 | Dancing plague of 1518 | 140,216 |
Dancing plague of 1518 Waller speculates that the dancing was "stress-induced psychosis" on a mass level, since the region where the people danced was riddled with starvation and disease, and the inhabitants tended to be superstitious. Seven other cases of dancing plague were reported in the same region during the medieval era. This could have been a florid example of psychogenic movement disorder happening in mass hysteria or mass psychogenic illness, which involves many individuals—small groups to almost 1,000 people—suddenly exhibiting the same bizarre behavior. The behavior spreads rapidly and broadly in an epidemic pattern. This kind of comportment could have been caused by the elevated levels of psychological stress, i.e. the despair caused by the ruthless years (even by the rough standards of the Middle Ages) the people of Alsace were suffering. This psychogenic illness could have created a chorea (Greek khoreia or "to dance"), a situation comprising random and intricate unintentional movements that flit from body part to body part. Diverse choreas (St. Vitus' dance, St. John's dance, tarantism) were labeled in the Middle Ages referring to the independent epidemics of "dancing mania" that happened in central Europe, particularly at the time of the plague. | Biology | https://en.wikipedia.org/wiki?curid=18776822 | Dancing plague of 1518 | 140,217 |
Chloragogen cell Chloragogen cells, also called as "y cells", are cells in annelids that function similarly to the liver in vertebrates. The cells store glycogen and neutralize toxins and are present in coelomic fluid of some annelids. They are yellowish in colour due to the presence of yellow granules called chloragosomes. These cells are derived from the inner coelomic epithelium, and help in excretory functions, as most commonly demonstrated in earthworms. They have characteristic vesicular bulging which store and transport substances like glycogen and nitrogenous wastes. They take part in the deamination of amino acids and synthesis of urea. Silicates taken in along with food are deposited in the chloragogen cells. | Biology | https://en.wikipedia.org/wiki?curid=18776997 | Chloragogen cell | 140,218 |
Quaternary extinction event The Quaternary period (from 2.588 ± 0.005 million years ago to the present) saw the extinctions of numerous predominantly megafaunal species, which resulted in a collapse in faunal density and diversity and the extinction of key ecological strata across the globe. The most prominent event in the Late Pleistocene is differentiated from previous Quaternary pulse extinctions by the widespread absence of ecological succession to replace these extinct species, and the regime shift of previously established faunal relationships and habitats as a consequence. The earliest casualties were incurred at 130,000 BCE (the start of the Late Pleistocene). However, the great majority of extinctions in Afro-Eurasia and the Americas occurred during the transition from the Pleistocene to the Holocene epoch (13,000 BCE to 8,000 BCE). This extinction wave did not stop at the end of the Pleistocene, continuing, especially on isolated islands, in human-caused extinctions, although there is debate as to whether these should be considered separate events or part of the same event. Among the main causes hypothesized by paleontologists are overkill by the widespread appearance of humans and natural climate change. A notable modern human presence first appeared during the Middle Pleistocene in Africa, and started to establish continuous, permanent populations in Eurasia and Australasia from 120,000 BCE and 63,000 BCE respectively, and the Americas from 22,000 BCE | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,219 |
Quaternary extinction event A variant of the former possibility is the second-order predation hypothesis, which focuses more on the indirect damage caused by overcompetition with nonhuman predators. Recent studies have tended to favor the human-overkill theory. The Late Pleistocene extinction event saw the extinction of many mammals weighing more than 40 kg. The proportional rate of megafauna extinctions is progressively larger the greater the human migratory distance from Africa. The extinctions in the Americas entailed the elimination of all the larger (over 100 kg) mammalian species of South American origin, including those that had migrated north in the Great American Interchange. Only in the continents of Australia, North America, and South America did the extinction occur at family taxonomic levels or higher. The proportional rate of megafauna extinctions being incrementally bigger the larger the migratory distance from Africa might be related to non-African megafauna and "Homo sapiens" not having evolved as species alongside each other. For their part, Australia, North America and South America, which respectively had the highest incremental extinction rates, had no known native species of Hominoidea (apes) at all, and specifically no species of Hominidae (greater apes) or "Homo". The increased rate of extinction mirrors the sequential pattern of the migration of anatomically modern humans | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,220 |
Quaternary extinction event The further away from Africa, the more recently the area has been inhabited by humans, and the less time the environments (including its megafauna) had had to become accustomed to humans and vice versa. There is no evidence of megafaunal extinctions at the height of the Last Glacial Maximum, indicating that increasing cold and glaciation were not factors. There are three main hypotheses concerning the Pleistocene extinction: There are some inconsistencies between the current available data and the prehistoric overkill hypothesis. For instance, there are ambiguities around the timing of sudden extinctions of Australian megafauna. Biologists note that comparable extinctions have not occurred in Africa and South or Southeast Asia, where the fauna evolved with hominids. Post-glacial megafaunal extinctions in Africa have been spaced over a longer interval. Evidence supporting the prehistoric overkill hypothesis includes the persistence of certain island megafauna for several millennia past the disappearance of their continental cousins. Ground sloths survived on the Antilles long after North and South American ground sloths were extinct. The later disappearance of the island species correlates with the later colonization of these islands by humans. Similarly, woolly mammoths died out on remote Wrangel Island 1,000 years after their extinction on the mainland | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,221 |
Quaternary extinction event Steller's sea cows also persisted in seas off the isolated and uninhabited Commander Islands for thousands of years after they had vanished from the continental shores of the north Pacific. Alternative hypotheses to the theory of human responsibility include climate change associated with the last glacial period and the Younger Dryas event, as well as Tollmann's hypothetical bolide, which claim that the extinctions resulted from bolide impact(s). Such a scenario has been proposed as a contributing cause of the 1,300-year cold period known as the Younger Dryas stadial. This impact extinction hypothesis is still in debate due to the exacting field techniques required to extract minuscule particles of extraterrestrial impact markers such as iridium at a high resolution from very thin strata in a repeatable fashion, as is necessary to conclusively distinguish the event peak from the local background level of the marker. The debate seems to be exacerbated by infighting between the Uniformitarianism camp and the Catastrophism camp. Recent research indicates that each single species responded differently to environmental changes, and that one factor by itself cannot explain the large number of extinctions. The causes are complex, and may involve elements of climate change, interspecific competition, unstable population dynamics, and human predation. The Afrotropic and Indomalaya biogeographic realms, or Old World tropics, were relatively spared by the Late Pleistocene extinctions | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,222 |
Quaternary extinction event Sub-Saharan Africa and southern Asia are the only regions that have terrestrial mammals weighing over 1000 kg today. However, there are indications of megafaunal extinction events throughout the Pleistocene, particularly in Africa two million years ago, which coincide with key stages of human evolution and climatic trends. The center of human evolution and expansion, Africa and Asia were inhabited by advanced hominids by 2mya, with "Homo habilis" in Africa, and "Homo erectus" on both continents. By the advent and proliferation of "Homo sapiens" circa 315,000 BCE, dominant species included "Homo heidelbergensis" in Africa, the denisovans and neanderthals (fellow "H. heidelbergensis" descendants) in Eurasia, and "Homo erectus" in Eastern Asia. Ultimately, on both continents, these groups and other populations of Homo were subsumed by successive radiations of "H. sapiens". There is evidence of an early migration event 268,000 BCE and later within neanderthal genetics, however the earliest dating for "H. sapiens" inhabitation is 118,000 BCE in Arabia, China and Israel, and 71,000 BCE in Indonesia. Additionally, not only have these early Asian migrations left a genetic mark on modern Papuan populations, the oldest known pottery in existence was found in China, dated to 18,000 BCE. Particularly during the late Pleistocene, megafaunal diversity was notably reduced from both these continents, often without being replaced by comparable successor fauna | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,223 |
Quaternary extinction event Climate change has been explored as a prominent cause of extinctions in Southeast Asia. Megafauna that disappeared in Africa or Asia during the Early and Middle Pleistocene include: The Palearctic realm spans the entirety of the European continent and stretches into northern Asia, through the Caucasus and central Asia to northern China, Siberia and Beringia. During the Late Pleistocene, this region was noted for its great diversity and dynamism of biomes, including the warm climes of the Mediterranean basin, open temperate woodlands, arid plains, mountainous heathland and swampy wetlands, all of which were vulnerable to the severe climatic fluctuations of the interchanges between glacial and interglacials periods (stadials). However, it was the expansive mammoth steppe which was the ecosystem which united and defined this region during the Late Pleistocene. One of the key features of Europe's Late Pleistocene climate was the often drastic turnover of conditions and biota between the numerous stadials, which could set within a century. For example, during glacial periods, the entire North Sea was drained of water to form Doggerland. The final major cold spell occurred from 25,000 BCE to 18,000 BCE and is known as the Last Glacial Maximum, when the Fenno-Scandinavian ice sheet covered much of northern Europe, while the Alpine ice sheet occupied significant parts of central-southern Europe | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,224 |
Quaternary extinction event Europe and northern Asia, being far colder and drier than today, was largely hegemonized by the mammoth steppe, an ecosystem dominated by palatable high-productivity grasses, herbs and willow shrubs. This supported an extensive biota of grassland fauna and stretched eastwards from Spain in the Iberian Peninsula to Yukon in modern-day Canada. The area was populated by many species of grazers which assembled in large herds similar in size to those in Africa today. Populous species which roamed the great grasslands included the woolly mammoth, woolly rhinoceros, "Elasmotherium", steppe bison, Pleistocene horse, muskox, "Cervalces", reindeer, various antelopes (Goat-horned antelope, mongolian gazelle, saiga antelope and twisted-horned antelope) and steppe pika. Carnivores included Eurasian cave lion, scimitar cat, cave hyena, grey wolf, dhole and the Arctic fox. At the edges of these large stretches of grassland could be found more shrub-like terrain and dry conifer forests and woodland (akin to forest steppe or taiga). The browsing collective of megafauna included woolly rhinoceros, giant deer, moose, "Cervalces", tarpan, aurochs, woodland bison, camels and smaller deer (Siberian roe deer, red deer and Siberian musk deer). Brown bears, wolverines, cave bear, wolves, lynx, leopards and red foxes also inhabited this biome. Tigers were at stages also present, from the edges of eastern Europe around the Black Sea to Beringia | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,225 |
Quaternary extinction event The more mountainous terrain, incorporating montane grasslands, subalpine conifer forests, alpine tundra and broken, craggy slopes, was occupied by several species of mountain-going animals like argali, chamois, ibex, mouflon, pika, wolves, leopards, "Ursus sp." and lynx, with snow leopards, Baikal yak and snow sheep in northern Asia. Arctic tundra, which lined the north of the mammoth steppe, reflected modern ecology with species such as the polar bear, wolf, reindeer and muskox. Other biomes, although less noted, were significant in contributing to the diversity of fauna in Late Pleistocene Europe. Warmer grasslands such as temperate steppes and Mediterranean savannahs hosted "Stephanorhinus", gazelle, European bison, Asian ostriches, "Leptobos", cheetah and onager. These biomes also contained an assortment of mammoth steppe fauna, such as saiga antelope, lions, scimitar cats, cave hyenas, wolves, Pleistocene horse, steppe bison, twisted-horned antelope, aurochs and camels. Temperate coniferous, deciduous, mixed broadleaf and Mediterranean forests and open woodlands accommodated straight-tusked elephants, "Praemegaceros", "Stephanorhinus", wild boar, bovids such as European bison, tahr and tur, species of "Ursus" such as the Etruscan bear and smaller deer (Roe deer, red deer, fallow deer and Mediterranean deer) with several mammoth steppe species such as lynx, tarpan, wolves, dholes, moose, giant deer, woodland bison, leopards and aurochs | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,226 |
Quaternary extinction event Woolly rhinoceros and mammoth occasionally resided in these temperate biomes, mixing with predominately temperate fauna to escape harsh glacials. In warmer wetlands, European water buffalo and hippopotamus were present. Although these habitats were restricted to micro refugia and to southern Europe and its fringes, being in Iberia, Italy, the Balkans, Ukraine's Black Sea basin, the Caucasus and western Asia, during inter-glacials these biomes had a far more northernly range. For example, hippopotamus inhabited Great Britain and straight-tusked elephant the Netherlands, as recently as 80,000 BCE and 42,000 BCE respectively. The first possible indications of habitation by hominins are the 7.2 million year old finds of "Graecopithecus", and 5.7 million year old footprints in Crete — however established habitation is noted in Georgia from 1.8 million years ago, proceeded to Germany and France, by "Homo erectus". Prominent co-current and subsequent species include "Homo antecessor", "Homo cepranensis", "Homo heidelbergensis", neanderthals and denisovans, preceding habitation by Homo sapiens circa 38,000 BCE. Extensive contact between African and Eurasian Homo groups is known at least in part through transfers of stone-tool technology in 500,000 BCE and again at 250,000 BCE. Europe's Late Pleistocene biota went through two phases of extinction. Some fauna became extinct before 13,000 BCE, in staggered intervals, particularly between 50,000 BCE and 30,000 BCE | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,227 |
Quaternary extinction event Species include cave bear, "Elasmotherium", straight-tusked elephant, "Stephanorhinus", water buffalo, neanderthals, gazelle and scimitar cat. However, the great majority of species were extinguished, extirpated or experienced severe population contractions between 13,000 BCE and 9,000 BCE, ending with the Younger Dryas. At that time there were small ice sheets in Scotland and Scandinavia. The mammoth steppe disappeared from the vast majority of its former range, either due to a permanent shift in climatic conditions, or an absence of ecosystem management due to decimated, fragmented or extinct populations of megaherbivores. This led to a region wide extinction vortex, resulting in cyclically diminishing bio-productivity and defaunation. Insular species on Mediterranean islands such as Sardinia, Sicily, Malta, Cyprus and Crete, went extinct around the same time as humans colonised those islands. Fauna included dwarf elephants, megacerines and hippopotamuses, and giant avians, otters and rodents. Many species extant today were present in areas either far to the south or west of their contemporary ranges. For example, all the Arctic fauna on this list inhabited regions as south as the Iberian Peninsula at various stages of the Late Pleistocene. "See also:" "List of North American animals extinct in the Holocene" During the last 60,000 years, including the end of the last glacial period, approximately 51 genera of large mammals have become extinct in North America | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,228 |
Quaternary extinction event Of these, many genera extinctions can be reliably attributed to a brief interval of 11,500 to 10,000 radiocarbon years before present, shortly following the arrival of the Clovis people in North America . Prominent paleontological sites include Mexico and Panama, the crossroads of the American Interchange. Most other extinctions are poorly constrained in time, though some definitely occurred outside of this narrow interval. In contrast, only about half a dozen small mammals disappeared during this time. Previous North American extinction pulses had occurred at the end of glaciations, but not with such an ecological imbalance between large mammals and small ones (Moreover, previous extinction pulses were not comparable to the Quaternary extinction event; they involved primarily species replacements within ecological niches, while the latter event resulted in many ecological niches being left unoccupied). Such include the last native North American terror bird ("Titanis"), rhinoceros ("Aphelops") and hyena ("Chasmaporthetes"). Human habitation commenced unequivacolly approximately 22,000 BCE north of the glacier, and 13,500 BCE south, however disputed evidence of southern human habitation exists from 130,000 BCE and 17,000 BCE onwards, described from sites in California and Meadowcroft in Pennsylvania | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,229 |
Quaternary extinction event North American extinctions (noted as herbivores (H) or carnivores (C)) included: The survivors are in some ways as significant as the losses: bison (H), grey wolf (C), lynx (C), grizzly bear (C), American black bear (C), deer (e.g. caribou, moose, wapiti (elk), "Odocoileus" sp.) (H), pronghorn (H), white-lipped peccary (H), muskox (H), bighorn sheep (H), and mountain goat (H); the list of survivors also include species which were extirpated during the Quaternary extinction event, but recolonised at least part of their ranges during the mid-holocene from South American relict populations, such as the cougar (C), jaguar (C), giant anteater (C), collared peccary (H), ocelot (C) and jaguarundi (C). All save the pronghorns and giant anteaters were descended from Asian ancestors that had evolved with human predators. Pronghorns are the second-fastest land mammal (after the cheetah), which may have helped them elude hunters. More difficult to explain in the context of overkill is the survival of bison, since these animals first appeared in North America less than 240,000 years ago and so were geographically removed from human predators for a sizeable period of time. Because ancient bison evolved into living bison, there was no continent-wide extinction of bison at the end of the Pleistocene (although the genus was regionally extirpated in many areas). The survival of bison into the Holocene and recent times is therefore inconsistent with the overkill scenario | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,230 |
Quaternary extinction event By the end of the Pleistocene, when humans first entered North America, these large animals had been geographically separated from intensive human hunting for more than 200,000 years. Given this enormous span of geologic time, bison would almost certainly have been very nearly as naive as native North American large mammals. The culture that has been connected with the wave of extinctions in North America is the paleo-American culture associated with the Clovis people ("q.v."), who were thought to use spear throwers to kill large animals. The chief criticism of the "prehistoric overkill hypothesis" has been that the human population at the time was too small and/or not sufficiently widespread geographically to have been capable of such ecologically significant impacts. This criticism does not mean that climate change scenarios explaining the extinction are automatically to be preferred by default, however, any more than weaknesses in climate change arguments can be taken as supporting overkill. Some form of a combination of both factors could be plausible, and overkill would be a lot easier to achieve large-scale extinction with an already dying population due to climate change. Lack of tameable megafauna was perhaps one of the reasons why Amerindian civilizations evolved differently from Old World ones. Critics have disputed this by arguing that llamas, alpacas, and bison were domesticated | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,231 |
Quaternary extinction event The Neotropic realm was affected by the fact that South America had been isolated as an island continent for many millions of years, and had a wide range of fauna found nowhere else, although many of them became extinct during the Great American Interchange about 3 million years ago, such as the "Sparassodonta" family. Those that survived the interchange included the ground sloths, glyptodonts, litopterns, pampatheres, phorusrhacids (terror birds) and notoungulates; all managed to extend their range to North America. [https://www.floridamuseum.ufl.edu/files/7513/9447/0046/bulletin-Mcdonaldlowres.pdf <nowiki>[3]</nowiki>] In the Pleistocene, South America remained largely unglaciated except for increased mountain glaciation in the Andes, which had a two-fold effect- there was a faunal divide between the Andes, and the colder, arid interior resulted in the advance of temperate lowland woodlands, tropical savannas and deserts at the expense of rainforests. Within these open environments, megafauna diversity was extremely dense, with over 40 genera recorded from the Guerrero member of Luján Formation alone. Ultimately, by the mid-Holocene, all the preeminent genera of megafauna became extinct- the last specimens of "Doedicurus" and "Toxodon" have been dated to 4,555 BCE and 3,000 BCE respectively. Their smaller relatives remain, including anteaters, tree sloths, armadillos; New World marsupials: opossums, shrew opossums, and the monito del monte (actually more related to Australian marsupials) | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,232 |
Quaternary extinction event Intense human habitation was established circa 11,000 BCE, however partly disputed evidence of pre-clovis habitation occurs since 46,000 BCE and 20,000 BCE, such as at the Serra da Capivara National Park (Brazil) and Monte Verde (Chile) sites. Today the largest land mammals remaining in South America are the wild camels of the "Lamini" group, such as the guanacos and vicuñas, and the "Tapirus" genus, of which Baird's tapir can reach up to 400 kg. Other notable surviving large fauna are peccaries, marsh deer ("Capreolinae"), giant anteaters, spectacled bears, maned wolves, pumas, ocelots, jaguars, rheas, emerald tree boas, boa constrictors, anacondas, American crocodiles, caimans, and giant rodents such as capybaras. In Sahul (a former continent composed of Australia and New Guinea), the sudden and extensive spate of extinctions occurred earlier than in the rest of the world. Most evidence points to a 20,000 year period after human arrival circa 63,000 BCE, but scientific argument continues as to the exact date range. In the rest of the Pacific (other Australasian islands such as New Caledonia, and Oceania) although in some respects far later, endemic fauna also usually perished quickly upon the arrival of humans in the late Pleistocene and early Holocene. This section does only include extinctions that took place prior to European discovery of the respective islands | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,233 |
Quaternary extinction event The extinctions in the Pacific included: Some extinct megafauna, such as the bunyip-like "Diprotodon", may remain in folk memory or be the sources of cryptozoological legends. There is no general agreement on where the Holocene, or anthropogenic, extinction begins, and the ends, or if they should be considered separate events at all. Some have suggested that anthropogenic extinctions may have begun as early as when the first modern humans spread out of Africa between 100,000 and 200,000 years ago, which is supported by rapid megafaunal extinction following recent human colonisation in Australia, New Zealand and Madagascar, in a similar way that any large, adaptable predator moving into a new ecosystem would. In many cases, it is suggested even minimal hunting pressure was enough to wipe out large fauna, particularly on geographically isolated islands. Only during the most recent parts of the extinction have plants also suffered large losses. Overall, the Holocene extinction can be characterised by the human impact on the environment. The Holocene extinction continues into the 21st century, with overfishing, ocean acidification and the amphibian crisis being a few broader examples of an almost universal, cosmopolitan decline of biodiversity. The hunting hypothesis suggests that humans hunted megaherbivores to extinction, which in turn caused the extinction of carnivores and scavengers which had preyed upon those animals | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,234 |
Quaternary extinction event Therefore, this hypothesis holds Pleistocene humans responsible for the megafaunal extinction. One variant, known as "blitzkrieg", portrays this process as relatively quick. Some of the direct evidence for this includes: fossils of some megafauna found in conjunction with human remains, embedded arrows and tool cut marks found in megafaunal bones, and European cave paintings that depict such hunting. Biogeographical evidence is also suggestive: the areas of the world where humans evolved currently have more of their Pleistocene megafaunal diversity (the elephants and rhinos of Asia and Africa) compared to other areas such as Australia, the Americas, Madagascar and New Zealand without the earliest humans. A picture arises of the megafauna of Asia and Africa evolving alongside humans, learning to be wary of them, and in other parts of the world the wildlife appearing ecologically naive and easier to hunt. This is particularly true of island fauna, which display a disastrous lack of fear of humans. Of course, it is impossible to demonstrate this naïveté directly in ancient fauna. Circumstantially, the close correlation in time between the appearance of humans in an area and extinction there provides weight for this scenario. The megafaunal extinctions covered a vast period of time and highly variable climatic situations. The earliest extinctions in Australia were complete approximately 50,000 BP, well before the last glacial maximum and before rises in temperature | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,235 |
Quaternary extinction event The most recent extinction in New Zealand was complete no earlier than 500 BP and during a period of cooling. In between these extremes megafaunal extinctions have occurred progressively in such places as North America, South America and Madagascar with no climatic commonality. The only common factor that can be ascertained is the arrival of humans. This phenomenon appears even within regions. The mammal extinction wave in Australia about 50,000 years ago coincides not with known climatic changes, but with the arrival of humans. In addition, large mammal species like the giant kangaroo "Protemnodon" appear to have succumbed sooner on the Australian mainland than on Tasmania, which was colonised by humans a few thousand years later. Worldwide, extinctions seem to follow the migration of humans and to be most severe where humans arrived most recently and least severe where humans originated — in Africa (see figure "March of Man" below). This suggests that prey animals and human hunting ability evolved together, so the animals evolved avoidance techniques. As humans migrated throughout the world and became more and more proficient at hunting, they encountered animals that had evolved without the presence of humans. Lacking the fear of humans that African animals had developed, animals outside of Africa were easy prey for human hunting techniques. It also suggests that this is independent of climate change | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,236 |
Quaternary extinction event Extinction through human hunting has been supported by archaeological finds of mammoths with projectile points embedded in their skeletons, by observations of modern naïve animals allowing hunters to approach easily and by computer models by Mosimann and Martin, and Whittington and Dyke, and most recently by Alroy. A study published in 2015 supported the hypothesis further by running several thousand scenarios that correlated the time windows in which each species is known to have become extinct with the arrival of humans on different continents or islands. This was compared against climate reconstructions for the last 90,000 years. The researchers found correlations of human spread and species extinction indicating that the human impact was the main cause of the extinction, while climate change exacerbated the frequency of extinctions. The study, however, found an apparently low extinction rate in the fossil record of mainland Asia. The overkill hypothesis, a variant of the hunting hypothesis, was proposed in 1966 by Paul S. Martin, Professor of Geosciences Emeritus at the Desert Laboratory of the University of Arizona. The major objections to the theory are as follows: At the end of the 19th and beginning of the 20th centuries, when scientists first realized that there had been glacial and interglacial ages, and that they were somehow associated with the prevalence or disappearance of certain animals, they surmised that the termination of the Pleistocene ice age might be an explanation for the extinctions | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,237 |
Quaternary extinction event Critics object that since there were glacial in the evolutionary history of many of the megafauna, it is rather implausible that only after the last glacial maximum would there be such extinctions. However, this criticism is rejected by a recent study indicating that terminal Pleistocene megafaunal community composition may have differed markedly from faunas present during earlier interglacials, particularly with respect to the great abundance and geographic extent of Pleistocene "Bison" at the end of the epoch. This suggests that the survival of megafaunal populations during earlier interglacials is essentially irrelevant to the terminal Pleistocene extinction event, because bison were not present in similar abundance during any of the earlier interglacials. Some evidence weighs against climate change as a valid hypothesis as applied to Australia. It has been shown that the prevailing climate at the time of extinction (40,000–50,000 BP) was similar to that of today, and that the extinct animals were strongly adapted to an arid climate. The evidence indicates that all of the extinctions took place in the same short time period, which was the time when humans entered the landscape. The main mechanism for extinction was probably fire (started by humans) in a then much less fire-adapted landscape. Isotopic evidence shows sudden changes in the diet of surviving species, which could correspond to the stress they experienced before extinction | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,238 |
Quaternary extinction event Evidence in Southeast Asia, in contrast to Europe, Australia, and the Americas, suggests that climate change and an increasing sea level were significant factors in the extinction of several herbivorous species. Alterations in vegetation growth and new access routes for early humans and mammals to previously isolated, localized ecosystems were detrimental to select groups of fauna. Some evidence obtained from analysis of the tusks of mastodons from the American Great Lakes region appears inconsistent with the climate change hypothesis. Over a span of several thousand years prior to their extinction in the area, the mastodons show a trend of declining age at maturation. This is the opposite of what one would expect if they were experiencing stresses from deteriorating environmental conditions, but is consistent with a reduction in intraspecific competition that would result from a population being reduced by human hunting. The most obvious change associated with the termination of an ice age is the increase in temperature. Between 15,000 BP and 10,000 BP, a 6 °C increase in global mean annual temperatures occurred. This was generally thought to be the cause of the extinctions. According to this hypothesis, a temperature increase sufficient to melt the Wisconsin ice sheet could have placed enough thermal stress on cold-adapted mammals to cause them to die | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,239 |
Quaternary extinction event Their heavy fur, which helps conserve body heat in the glacial cold, might have prevented the dumping of excess heat, causing the mammals to die of heat exhaustion. Large mammals, with their reduced surface area-to-volume ratio, would have fared worse than small mammals. A study covering the past 56,000 years indicates that rapid warming events with temperature changes of up to had an important impact on the extinction of megafauna. Ancient DNA and radiocarbon data indicates that local genetic populations were replaced by others within the same species or by others within the same genus. Survival of populations was dependent on the existence of refugia and long distance dispersals, which may have been disrupted by human hunters. Studies propose that the annual mean temperature of the current interglacial that we have seen for the last 10,000 years is no higher than that of previous interglacials, yet some of the same large mammals survived similar temperature increases. Therefore, warmer temperatures alone may not be a sufficient explanation. In addition, numerous species such as mammoths on Wrangel Island and St. Paul Island survived in human-free refugia despite changes in climate. This would not be expected if climate change were responsible (unless their maritime climates offered some protection against climate change not afforded to coastal populations on the mainland) | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,240 |
Quaternary extinction event Under normal ecological assumptions island populations should be more vulnerable to extinction due to climate change because of small populations and an inability to migrate to more favorable climes. Other scientists have proposed that increasingly extreme weather—hotter summers and colder winters—referred to as "continentality", or related changes in rainfall caused the extinctions. The various hypotheses are outlined below. It has been shown that vegetation changed from mixed woodland-parkland to separate prairie and woodland. This may have affected the kinds of food available. Shorter growing seasons may have caused the extinction of large herbivores and the dwarfing of many others. In this case, as observed, bison and other large ruminants would have fared better than horses, elephants and other monogastrics, because ruminants are able to extract more nutrition from limited quantities of high-fiber food and better able to deal with anti-herbivory toxins. So, in general, when vegetation becomes more specialized, herbivores with less diet flexibility may be less able to find the mix of vegetation they need to sustain life and reproduce, within a given area. Increased continentality resulted in reduced and less predictable rainfall limiting the availability of plants necessary for energy and nutrition. Axelrod and Slaughter have suggested that this change in rainfall restricted the amount of time favorable for reproduction | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,241 |
Quaternary extinction event This could disproportionately harm large animals, since they have longer, more inflexible mating periods, and so may have produced young at unfavorable seasons (i.e., when sufficient food, water, or shelter was unavailable because of shifts in the growing season). In contrast, small mammals, with their shorter life cycles, shorter reproductive cycles, and shorter gestation periods, could have adjusted to the increased unpredictability of the climate, both as individuals and as species which allowed them to synchronize their reproductive efforts with conditions favorable for offspring survival. If so, smaller mammals would have lost fewer offspring and would have been better able to repeat the reproductive effort when circumstances once more favored offspring survival. In 2017 a study looked at the environmental conditions across Europe, Siberia and the Americas from 25,000–10,000 YBP. The study found that prolonged warming events leading to deglaciation and maximum rainfall occurred just prior to the transformation of the rangelands that supported megaherbivores into widespread wetlands that supported herbivore-resistant plants. The study proposes that moisture-driven environmental change led to the megafaunal extinctions and that Africa's trans-equatorial position allowed rangeland to continue to exist between the deserts and the central forests, therefore fewer megafauna species became extinct there. Critics have identified a number of problems with the continentality hypotheses | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,242 |
Quaternary extinction event The extinction of the megafauna could have caused the disappearance of the mammoth steppe. Alaska now has low nutrient soil unable to support bison, mammoths, and horses. R. Dale Guthrie has claimed this as a cause of the extinction of the megafauna there; however, he may be interpreting it backwards. The loss of large herbivores to break up the permafrost allows the cold soils that are unable to support large herbivores today. Today, in the arctic, where trucks have broken the permafrost grasses and diverse flora and fauna can be supported. In addition, Chapin (Chapin 1980) showed that simply adding fertilizer to the soil in Alaska could make grasses grow again like they did in the era of the mammoth steppe. Possibly, the extinction of the megafauna and the corresponding loss of dung is what led to low nutrient levels in modern-day soil and therefore is why the landscape can no longer support megafauna. It may be observed that neither the overkill nor the climate change hypotheses can fully explain events: browsers, mixed feeders and non-ruminant grazer species suffered most, while relatively more ruminant grazers survived. However, a broader variation of the overkill hypothesis may predict this, because changes in vegetation wrought by either Second Order Predation (see below) or anthropogenic fire preferentially selects against browse species. The hyperdisease hypothesis attributes the extinction of large mammals during the late Pleistocene to indirect effects of the newly arrived aboriginal humans | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,243 |
Quaternary extinction event The Hyperdisease Hypothesis proposes that humans or animals traveling with them (e.g., chickens or domestic dogs) introduced one or more highly virulent diseases into vulnerable populations of native mammals, eventually causing extinctions. The extinction was biased toward larger-sized species because smaller species have greater resilience because of their life history traits (e.g., shorter gestation time, greater population sizes, etc.). Humans are thought to be the cause because other earlier immigrations of mammals into North America from Eurasia did not cause extinctions. Diseases imported by people have been responsible for extinctions in the recent past; for example, bringing avian malaria to Hawaii has had a major impact on the isolated birds of the island. If a disease was indeed responsible for the end-Pleistocene extinctions, then there are several criteria it must satisfy (see Table 7.3 in MacPhee & Marx 1997). First, the pathogen must have a stable carrier state in a reservoir species. That is, it must be able to sustain itself in the environment when there are no susceptible hosts available to infect. Second, the pathogen must have a high infection rate, such that it is able to infect virtually all individuals of all ages and sexes encountered. Third, it must be extremely lethal, with a mortality rate of c. 50–75%. Finally, it must have the ability to infect multiple host species without posing a serious threat to humans | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,244 |
Quaternary extinction event Humans may be infected, but the disease must not be highly lethal or able to cause an epidemic. One suggestion is that pathogens were transmitted by the expanding humans via the domesticated dogs they brought with them. Unfortunately for such a theory it can not account for several major extinction events, notably Australia and North America. Dogs did not arrive in Australia until approximately 35,000 years after the first humans arrived and approximately 30,000 years after the megafaunal extinction was complete and as such can not be implicated. In contrast numerous species including wolves, mammoths, camelids and horses had emigrated continually between Asia and North America over the past 100,000 years. For the disease hypothesis to be applicable in the case of the Americas it would require that the population remain immunologically naive despite this constant transmission of genetic and pathogenic material. The Second-Order Predation Hypothesis says that as humans entered the New World they continued their policy of killing predators, which had been successful in the Old World but because they were more efficient and because the fauna, both herbivores and carnivores, were more naive, they killed off enough carnivores to upset the ecological balance of the continent, causing overpopulation, environmental exhaustion, and environmental collapse. The hypothesis accounts for changes in animal, plant, and human populations | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,245 |
Quaternary extinction event The scenario is as follows: This has been supported by a computer model, the Pleistocene extinction model (PEM), which, using the same assumptions and values for all variables (herbivore population, herbivore recruitment rates, food needed per human, herbivore hunting rates, etc.) other than those for hunting of predators. It compares the overkill hypothesis (predator hunting = 0) with second-order predation (predator hunting varied between 0.01 and 0.05 for different runs). The findings are that second-order predation is more consistent with extinction than is overkill (results graph at left). The Pleistocene extinction model is the only test of multiple hypotheses and is the only model to specifically test combination hypotheses by artificially introducing sufficient climate change to cause extinction. When overkill and climate change are combined they balance each other out. Climate change reduces the number of plants, overkill removes animals, therefore fewer plants are eaten. Second-order predation combined with climate change exacerbates the effect of climate change. (results graph at right). The second-order predation hypothesis is supported by the observation above that there was a massive increase in bison populations. First publicly presented at the Spring 2007 joint assembly of the American Geophysical Union in Acapulco, Mexico, the comet hypothesis suggests that the mass extinction was caused by a swarm of comets 12,900 years ago | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,246 |
Quaternary extinction event Using photomicrograph analysis, research published in January 2009 has found evidence of nanodiamonds in the soil from six sites across North America including Arizona, Minnesota, Oklahoma, South Carolina and two Canadian sites. Similar research found nanodiamonds in the Greenland ice sheet. Debate around this hypothesis has included, among other things, the lack of an impact crater, relatively small increased level of iridium in the soil, and the relative probability of such an event. That said, it took 10 years after publication of the Alvarez theory before scientists found the Chicxulub crater. If the bolide struck the Laurentide ice sheet as hypothesized by Firestone et al. (2007), we would not see the typical impact crater. A spike in platinum was found in the Greenland ice cores by Petaev et al. (2013), which they view as a global signal. Confirmation came in 2017 with the report that the Pt spike had been found at "11 widely separated archaeological bulk sedimentary sequences." Wolbach et al. reported in 2018 that "YDB peaks in Pt were observed at 28 sites" in total, including the 11 reported earlier and the one from Greenland. | Biology | https://en.wikipedia.org/wiki?curid=18783051 | Quaternary extinction event | 140,247 |
The Seven Pillars of Life are the essential principles of life described by Daniel E. Koshland in 2002 in order to create a universal definition of life. One stated goal of this universal definition is to aid in understanding and identifying artificial and extraterrestrial life. The seven pillars are Program, Improvisation, Compartmentalization, Energy, Regeneration, Adaptability, and Seclusion. These can be abbreviated as PICERAS. Koshland defines "Program" as an "organized plan that describes both the ingredients themselves and the kinetics of the interactions among ingredients as the living system persists through time." In natural life as it is known on Earth, the program operates through the mechanisms of nucleic acids and amino acids, but the concept of program can apply to other imagined or undiscovered mechanisms. "Improvisation" refers to the living system's ability to change its program in response to the larger environment in which it exists. An example of improvisation on earth is natural selection. "Compartmentalization" refers to the separation of spaces in the living system that allow for separate environments for necessary chemical processes. Compartmentalization is necessary to protect the concentration of the ingredients for a reaction from outside environments. Because living systems involve net movement in terms of chemical movement or body movement, and lose energy in those movements through entropy, energy is required for a living system to exist | Biology | https://en.wikipedia.org/wiki?curid=18789195 | The Seven Pillars of Life | 140,248 |
The Seven Pillars of Life The main source of energy on Earth is the sun, but other sources of energy exist for life on Earth, such as hydrogen gas or methane, used in chemosynthesis. "Regeneration" in a living system refers to the general compensation for losses and degradation in the various components and processes in the system. This covers the thermodynamic loss in chemical reactions, the wear and tear of larger parts, and the larger decline of components of the system in ageing. Living systems replace these losses by importing molecules from the outside environment, synthesizing new molecules and components, or creating new generations to start the system over again. "Adaptability" is the ability of a living system to respond to needs, dangers, or changes. It is distinguished from improvisation because the response is timely and does not involve a change of the program. Adaptability occurs from a molecular level to a behavioral level through feedback and feedforward systems. For example, an animal seeing a predator will respond to the danger with hormonal changes and escape behavior. "Seclusion" is the separation of chemical pathways and the specificity of the effect of molecules, so that processes can function separately within the living system. In organisms on Earth, proteins aid in seclusion because of their individualized structure that are specific for their function, so that they can efficiently act without affecting separate functions. Y. N. Zhuravlev and V. A | Biology | https://en.wikipedia.org/wiki?curid=18789195 | The Seven Pillars of Life | 140,249 |
The Seven Pillars of Life Avetisov have analyzed Koshland's seven pillars from the context of primordial life and, though calling the concept "elegant," point out that the pillars of compartmentalization, program, and seclusion don't apply well to the non-differentiated earliest life. | Biology | https://en.wikipedia.org/wiki?curid=18789195 | The Seven Pillars of Life | 140,250 |
Aggregate Spend is the process used in the United States to aggregate and monitor the total amount spent by healthcare manufacturers on individual healthcare professionals and organizations (HCP/O) through payments, gifts, honoraria, travel and other means. Also often referred to as the Physician Payments Sunshine Act, this initiative is a growing body of federal and state legislations intended to collectively address all or some of the following goals: Organizations monitored include pharmaceutical, biotechnology and, in some states, medical device organizations. On September 6, 2007, Senator Chuck Grassley (R-Iowa) introduced the Physician Payments Sunshine Act of 2007 (S. 2029). In March 2008, Rep. Peter DeFazio (D-Oregon) and Rep. Pete Stark (D-California) introduced a slightly different companion bill in the House of Representatives. (H.R. 5605). These bills were reintroduced in 111th Congress as the Physician Payments Sunshine Act of 2009 (S. 301 and H.R. 3138), again by Senator Chuck Grassley and in the House of Representatives by Rep. Baron Hill (D-Indiana). The bills all aimed to replace the differing state legislations with a single law, common to all 50 states. According to Ashley Glacel, the press secretary for the Senate Aging Committee, whose chairman, Herb Kohl, co-sponsored the bill, the Senate bill is more expansive because it also include Medical Device makers | Biology | https://en.wikipedia.org/wiki?curid=18797385 | Aggregate Spend | 140,251 |
Aggregate Spend The bills would amend the Social Security Act "to provide for transparency in the relationship between physicians and manufacturers of drugs, devices, or medical supplies for which payment is made under Medicare, Medicaid, or SCHIP." The bill proposed that each quarter, beginning on January 1, 2008, companies or their agents which manufacture drugs, medical devices, or medical supplies would be required to disclose all payments over $25 in value made "to a physician, or to an entity that a physician is employed by, has tenure with, or has an ownership interest in". The bill would also require manufacturers to provide details on the date, value and nature of the payment, such as whether it was for "food, entertainment, or gifts", "trips or travel", "a product or other item provided for less than market value", "participation in a medical conference, continuing medical education, or other educational or informational program or seminar, provision of materials related to such a conference or educational or informational program or seminar, or remuneration for promoting or participating in such a conference or educational or informational program or seminar", "product rebates or discounts", "consulting fees or honoraria" or "any other economic benefit". Companies would be required to submit a summary report in electronic format. The proposed penalties for breaches were "not less than $10,000, but not more than $100,000", for each such failure | Biology | https://en.wikipedia.org/wiki?curid=18797385 | Aggregate Spend | 140,252 |
Aggregate Spend The proposed federal law would undermine a stronger Vermont law if passed, according to state officials and advocacy groups. The reporting threshold under the proposed federal law is $500 - much higher than the $25 threshold found in a similar Vermont law passed five years ago. If passed, the federal bill would preempt the state law. In May 2008, the Pharmaceutical Research and Manufacturers of America stated that they supported a revised version of the bill, but only on condition of "the continued inclusion of the provision that preempts state law". In a media statement, the PhRMA president, Billy Tauzi,n stated that "PhRMA believes that preempting local and state marketing reporting or disclosure laws that have been enacted or are pending avoids a confusing myriad of local, state and federal requirements that confuse patients accessing the information and are overly burdensome and costly for those required to report." The federal bill was finally passed on March 21, 2010, as a provision under the Patient Protection and Affordable Care (PPAC) Act (https://www.cms.gov/LegislativeUpdate/downloads/PPACA.pdf), and several states — including California, Massachusetts, Minnesota, Maine, District of Columbia, West Virginia, Vermont and Nevada — have already passed their versions of the Sunshine Law. The federal law was due to go into effect from January 1, 2012, with the earliest reports (covering January - December 2012) mandated on or before March 31, 2013 | Biology | https://en.wikipedia.org/wiki?curid=18797385 | Aggregate Spend | 140,253 |
Aggregate Spend The penalties range from $10,000 to $100,000 for each violation, and can go up to $1 million. In February 2013 the planned dates for implementation were changed to: earliest reports to cover August - December 2013; submission by March 31, 2014. In February 2014 CMS (The Centers for Medicare & Medicaid Services) advised the planned submission dates and what would be submitted were changed. In essence this was because the required registration process, for those who would submit data and attest to the accuracy of that data, was not ready for use, nor were the supporting systems, people and processes for receiving the data On February 18, Open Payments registration and data submission for applicable manufacturers and applicable GPOs opened with a two-phased approach for the first reporting year of the new program: Phase 1 (February 18 through March 31) includes user registration in CMS’ Enterprise Portal (the gateway to CMS’ Enterprise Identity Management system (EIDM)) and submission of corporate profile information and summary aggregate 2013 (August - December) payment data. Phase 2 (begins in May and extends for no fewer than 30 days) includes industry registration in the Open Payments system, submission of detailed 2013( August - December) payment data, and legal attestation to the accuracy of the data | Biology | https://en.wikipedia.org/wiki?curid=18797385 | Aggregate Spend | 140,254 |
Aggregate Spend After Phase 2 submission is complete, physicians and teaching hospitals will have the opportunity to register with OpenPayments and view the transactions reported under their name, prior to it being made available to the public. During this review period, any reported transactions may be disputed by the recipient. If a transfer of value is disputed, it will still be publicized, but remain flagged as disputed, until the dispute has been resolved. compliance has been affected by individual state law compliance, which requires healthcare manufacturers to address and collect distinct spend types to comply with disclosure requirements at the HCP/O aggregate level. Minnesota, West Virginia, Vermont, California, Nevada, and Washington D.C. all have some type of gift-giving limit or disclosure law. Starting in July 2009, Massachusetts and Vermont Gift Ban Law became active with bans of $5,000 and $10,000 per violation respectively. Other states are evaluating similar options as well. On June 29, 2011, the Maine legislature passed House Paper No. 530 which was subsequently signed into law by Governor LePage on July 8, 2011, effectively repealing Maine’s aggregate spend reporting requirements (22 MRSA §2698-A) | Biology | https://en.wikipedia.org/wiki?curid=18797385 | Aggregate Spend | 140,255 |
Fat necrosis is a form of necrosis characterized by the action upon fat by digestive enzymes. In fat necrosis the enzyme lipase releases fatty acids from triglycerides. The fatty acids then complex with calcium to form soaps. These soaps appear as white chalky deposits. It is usually associated with trauma of the pancreas or acute pancreatitis.It can also occur in the breast, the salivary glands and neonates after a traumatic delivery. | Biology | https://en.wikipedia.org/wiki?curid=18798591 | Fat necrosis | 140,256 |
The Chemical Basis of Morphogenesis "The Chemical Basis of Morphogenesis" is an article that the English mathematician Alan Turing wrote in 1952. It describes how patterns in nature, such as stripes and spirals, can arise naturally from a homogeneous, uniform state. The theory, which can be called a reaction–diffusion theory of morphogenesis, has become a basic model in theoretical biology. Such patterns have come to be known as Turing patterns. For example, it has been postulated that the protein VEGFC can form Turing patterns to govern the formation of lymphatic vessels in the zebrafish embryo. Reaction–diffusion systems have attracted much interest as a prototype model for pattern formation. Patterns such as fronts, spirals, targets, hexagons, stripes and dissipative solitons are found in various types of reaction-diffusion systems in spite of large discrepancies e.g. in the local reaction terms. Such patterns have been dubbed "Turing patterns". Reaction–diffusion processes form one class of explanation for the embryonic development of animal coats and skin pigmentation. Another reason for the interest in reaction-diffusion systems is that although they represent nonlinear partial differential equations, there are often possibilities for an analytical treatment. | Biology | https://en.wikipedia.org/wiki?curid=18801936 | The Chemical Basis of Morphogenesis | 140,257 |
Nylon-eating bacteria and creationism The discovery of nylon-eating bacteria has been used by critics of creationism and intelligent design, in both print articles and on websites, to challenge creationist claims. These bacteria can produce novel enzymes that allow them to feed on by-products of nylon manufacture which did not exist prior to the invention of nylon in the 1930s. Critics of creationism have argued that this contradicts creationist claims that no new information can be added to a genome by mutation, and that proteins are too complex to evolve through a process of mutation and natural selection. Creationists have posted responses to these challenges on their own websites, which have in turn generated more responses from their critics. The issue was first raised by critics of creationism such as the National Center for Science Education, and New Mexicans for Science and Reason (NMSR) who stated that research refutes claims made by creationists and intelligent design proponents. The claims were that random mutation and natural selection can never add new information to a genome and that the odds against a useful new protein, such as an enzyme, arising through a process of random mutation would be prohibitively high. Physicist Dave Thomas, the President of NMSR, has stated that gene duplication and frame-shift mutations were powerful sources of random mutation | Biology | https://en.wikipedia.org/wiki?curid=18804548 | Nylon-eating bacteria and creationism | 140,258 |
Nylon-eating bacteria and creationism In particular, in response to comments by creationists such as Don Batten, NMSR has stated that it was these mutations that gave rise to nylonase, even if the genes were part of a plasmid as suggested by Batten. Proponents of creationism, such as Answers in Genesis and Creation Ministries International, have cited analyses posted by Don Batten that cited scientific research that showed the genes involved were on a plasmid, and stated that the phenomenon is evidence that plasmids in bacteria are a designed feature intended to allow bacteria to adapt easily to new food sources or cope with toxic chemicals. Batten stated It seems clear that plasmids are designed features of bacteria that enable adaptation to new food sources or the degradation of toxins. The details of just how they do this remains to be elucidated. The results so far clearly suggest that these adaptations did not come about by chance mutations, but by some designed mechanism. These claims have been dismissed. NMSR has stated that the gene duplication and frame-shift mutations that gave rise to nylonase were powerful sources of random mutation, whether or not the genes were part of a plasmid as suggested by Batten. A posting at TalkOrigins Archive by Ian Musgrave states that bacteria carry many genes in plasmids, particularly those involved in xenobiotic handling or metabolic functions. He states that in "Pseudomonas", most of the xenobiotic degradation genes are on plasmids | Biology | https://en.wikipedia.org/wiki?curid=18804548 | Nylon-eating bacteria and creationism | 140,259 |
Nylon-eating bacteria and creationism Therefore it is entirely likely that a xenobiotic handling enzyme will arise from mutations of xenobiotic handling genes. The fact that these genes are on plasmids does not invalidate the fact that they exist, and exist only in two strains of bacteria. Musgrave also criticized Batten for mis-stating the conclusions of some of the authors of the scientific literature on nylon-eating bacteria. MSNBC published an editorial from science writer Ker Than that stated that the evolution of the enzymes, known as nylonase, produced by nylon-eating bacteria was a compelling argument against the claim made by intelligent design proponents that specified complexity required an intelligent designer, since nylonase function was both specified and complex. The intelligent design proponent William Dembski posted a response that questioned whether the genetic changes that produced nylonase were complex enough to be considered specified complexity. Ken Miller said that intelligent design proponents claim that we can't see either design or evolution taking place and that therefore, according to the design proponents, intelligent design and evolution are both just matters of faith or world view. However, Miller said, the evolution of the enzyme nylonase, which scientists were able to repeat in the lab with another strain of bacteria, is one of a number of cases that show that evolution can be observed as it occurs. | Biology | https://en.wikipedia.org/wiki?curid=18804548 | Nylon-eating bacteria and creationism | 140,260 |
Phalanx Biotech Group was founded in 2002 as a result of collaboration between Taiwan's Industrial Technology Research Institute (ITRI) and several private companies and research institutes. It is a manufacturer of DNA microarrays and a provider of gene expression profiling and microRNA profiling services based in Hsinchu, Taiwan, San Diego, California, Shanghai, China, and in Beijing, China. The company sells its DNA microarrays and service platform under the registered trademark name OneArray. is a member of the FDA-led Microarray Quality Control Project. is a manufacturer and provider of DNA microarray products and services used for gene expression profiling and miRNA profiling. Human, Mouse, Rat and Yeast whole genome OneArray DNA microarrays are manufactured and used for gene expression profiling products and services. The miRNA profiling products and services include miRNA OneArray microarrays and related services for Human, Rodent, and many Model organism and Plant species. Other than the OneArray services, Phalanx also offers Agilent microarray services, qPCR services, PCR array profiling services, and NGS services. Each one of these services can be accompanied by an extensive, customizable bioinformatics package. The DNA microarrays are produced using a patented non-contact inkjet deposition of intact oligonucleotides. This is performed using a patented inkjet dispensing apparatus. The oligonucleotides are deposited on a standard size 25mm X 75mm glass slide. | Biology | https://en.wikipedia.org/wiki?curid=18812368 | Phalanx Biotech Group | 140,261 |
Narcolepsy is a long-term neurological disorder that involves a decreased ability to regulate sleep-wake cycles. Symptoms often include periods of excessive daytime sleepiness and brief involuntary sleep episodes. About 70% of those affected also experience episodes of sudden loss of muscle strength, known as cataplexy. These experiences can be brought on by strong emotions. Less commonly, there may be vivid hallucinations or an inability to move (sleep paralysis) while falling asleep or waking up. People with narcolepsy tend to sleep about the same number of hours per day as people without, but the quality of sleep tends to be lessened. The exact cause of narcolepsy is unknown, with potentially several causes. In up to 10% of cases, there is a family history of the disorder. Often, those affected have low levels of the neuropeptide "orexin", which may be due to an autoimmune disorder. Trauma, infections, toxins or psychological stress may also play a role. Diagnosis is typically based on the symptoms and sleep studies, after ruling out other potential causes. Excessive daytime sleepiness can also be caused by other sleep disorders such as sleep apnea, major depressive disorder, anemia, heart failure, drinking alcohol and not getting enough sleep. Cataplexy may be mistaken for seizures. While there is no cure, a number of lifestyle changes and medications may help. Lifestyle changes include taking regular short naps and sleep hygiene. Medications used include modafinil, sodium oxybate and methylphenidate | Biology | https://en.wikipedia.org/wiki?curid=18835541 | Narcolepsy | 140,262 |