Katherine Taylor, Quanta Magazine
As dinosaurs morphed into birds, they shrank dramatically and adopted a more babylike skull shape. Shown left to right: Velociraptor, a dinosaur of the class that gave rise to birds; Archaeopteryx, often called the first bird; and a modern chicken and pigeon.
“A bird didn’t just evolve from a T. rex overnight, but rather the classic features of birds evolved one by one; first bipedal locomotion, then feathers, then a wishbone, then more complex feathers that look like quill-pen feathers, then wings,” Stephen Brusatte, a paleontologist at the University of Edinburgh in Scotland said. “The end result is a relatively seamless transition between dinosaurs and birds, so much so that you can’t just draw an easy line between these two groups.”
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