Around 66 million years ago, the Chicxulub event changed the world when an asteroid slammed into the Yucatan Peninsula and plunged the world into a darkness that killed off 75% of the existing species. The dinosaurs were the best-known of the victims. But not all dinosaurs died out. The few that survived were birds. Even then, the surviving bird species were only a small percentage of the birds that existed before the asteroid impact.
Why these these particular species of birds survive? What's the difference between Cretaceous birds and those living today? It appears to be big brains. But it's not just size- new scans of Ichthyornis, a bird that went extinct after the asteroid impact, shows a small forebrain, or cerebrum, like many dinosaurs. Modern birds have much larger forebrains compared to their other brain structures. The forebrain is responsible for many functions, so scientists don't yet know exactly how a larger forebrain aided some birds' survival, but speculate that it might have made them more able to modify their behavior in the face of a new environment. Just don't call them birdbrains. Read more about this research at LiveScience. -via Damn Interesting
Image credit: Torres et al/CC BY 4.0)
#bird #dinosaur #birdevolution #extinction #asteroid #birdbrain