News Finding: Wills agrees that the new research makes this explanation for the Cambrian explosion "look a lot more probable now."
Paper Finding: That study suggested that reconstructing relationships between Cambrian lineages would be essentially impossible assuming constant evolutionary rates, unless they diverged gradually over a time period of >100 Myr.
News Context: Innovations such as exoskeletons, vision, and jaws created new niches and evolution sped up to fill them. Wills agrees that the new research makes this explanation for the Cambrian explosion "look a lot more probable now." "It's an excellent first step," says Douglas Erwin, a paleontologist at the Smithsonian Institution in Washington, D.C., but the exact rates of evolution in the study might not be reliable.
Paper Context: These results are robust to dating methods and calibration assumptions (Table S3) . That study suggested that reconstructing relationships between Cambrian lineages would be essentially impossible assuming constant evolutionary rates, unless they diverged gradually over a time period of >100 Myr. However, the same study showed that phylogenetic relationships in a ''Cambrian bush'' are resolvable if elevated evolutionary rates during the critical time window generated large suites of changes on chronologically short branches.