University of Michigan scientists have used artificial intelligence to uncover a striking pattern in the evolution of Passeriformes, the vast bird group that includes most songbirds. Their analysis suggests these birds did not evolve at a steady pace. Instead, major changes often arrived in rapid bursts that lined up with shifts in Earth's climate.
Evolutionary theory has long proposed that life diversifies through periods of fast change followed by slower phases. Fossils have offered clues that this pattern exists, but the new study identified it by analyzing skeletal measurements from modern bird specimens. The researchers also found that several of the most important evolutionary bursts occurred around periods of major climate change.
Evolution in Sudden Bursts
"This is really important for evolutionary theory because there's a long history, going back 100 years, that predicts the emergence of new groups, called evolutionary radiations, is often associated with an explosive burst of diversification. Evolutionary theory predicts that adaptive radiations may account for a large portion of the diversity of life on Earth," said Jake Berv, lead author of the study and postdoctoral fellow in the U-M School for Environment and Sustainability.
