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Birds Had To Relearn Flight After Meteor Wiped Out Dinosaurs, Fossil Records Suggest (theguardian.com)
An anonymous reader quotes a report from The Guardian: Birds had to rediscover flight after the meteor strike that killed off the dinosaurs, scientists say. The cataclysm 66 million years ago not only wiped out Tyrannosaurus rex and ground-dwelling dinosaur species, but also flying birds, a detailed survey of the fossil record suggests. As forests burned around the world, the only birds to survive were flightless emu-like species that lived on the ground. The six to nine-mile-wide meteor struck the Earth off the coast of Mexico, releasing a million times more energy than the largest atomic bomb. Hot debris raining from the sky is thought to have triggered global wildfires immediately after the impact. It took hundreds or even thousands of years for the world's forests of palms and pines to recover. Fossil records from New Zealand, Japan, Europe and North America, all show evidence of mass deforestation. They also reveal that birds surviving the end of the Cretaceous period had long sturdy legs made for living on the ground. They resembled emus and kiwis, said the researchers whose findings are reported in the journal Current Biology.
It's interesting that flightless birds had a pretty strong reign during the early recovery phases. They were often the dominant hunters of the time.
It's often speculated that mammals eventually replaced those giant flightless birds as the alpha hunters not because mammals are more powerful than big birds, but rather because mammals learned to better leverage pack hunting: social coordination. Otherwise, this era would have resembled Dinosaurs 2.0, with 40-foot birds: Sqaaawwwk!! BOOOM
Table-ized A.I.
Not suprising as it is also thought to have created a tsunami 330 feet tall along the coasts of Texas and flordia, but as high as 2.9 miles in deep ocean. It is 12 miles deep and 93 miles in diameter. It's pretty amazing as you can date the effects in many areas by the layer of material it spread over the whole world. Good thing these giant impacts are extremely rare because if we spot it late there is jack squat we could do.
According to some estimates that fallen debris may have heated the air to the temperature of a pizza oven. The ground dwelling birds and small mammals would have needed only 30-40 cm of ground to protect themselves from it. Also, animals capable of diving would have access to food supplies that had been protected from the heat and the resulting fires.
Crocodiles and turtles can survive longer periods without food than the bigger, presumably warm blooded dinosaurs and those aquatic species may have been vulnerable as their food chains were altered by the changing climate and marine chemistry from the impact and increasing pressure from the fish.