From Discovery.com:
All Birds Descend from One Feathered Founder
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The ancestry of every bird alive today can be traced back to a single “Founding Feathered Father” that lived in South America 95 million years ago, according to a new study.
The common ancestor of living birds, described in the journal Science Advances, likely lived much later than previously estimated. Prior reports suggested that the founding bird lived up to 170 million years ago during the Jurassic Period.
Dinosaurs (that didn’t evolve into birds) were still prevalent in South America 95 million years ago, yet the Founding Feathered Father would have been a standout.
So that’s less time for bird evolution?
Birds Evolved In ‘Big Bang,’ New Family Tree Reveals
“Rapid diversification around 66 million years ago has been interpreted as the effect of empty ecological niches left by the mass extinction (which killed off the dinosaurs and many other animals),” Claramunt said. “But our results show that rapid diversification began before the mass extinction event and coinciding with a long-term cooling trend at the end of the Cretaceous.” More.
A Big Bang of birds? See here for more on that.
See also: Conclusions: What the fossils told us in their own words