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A new study challenges the idea that the asteroid impact 66 million years ago led to a big pulse of bird evolution. The study found that birds began diversifying tens of millions of years before the impact, suggesting that the asteroid had no major effect on bird evolution.
I imagine this will ruffle a few feathers, said Scott Edwards, an evolutionary biologist at Harvard and one of the study's authors.
The fossil record has long supported the idea that the asteroid impact caused a burst of bird evolution, as the mass extinction of other species would have reduced competition for birds. However, the new study's analysis of DNA from 124 bird species indicates that bird diversification began long before the impact.
Dinosaurs evolved primitive feathers at least 200 million years ago, not for flight but most likely for insulation or a mating display.