Saturday Science: Reaching Critical Mass

No, it's not about atomic bombs. It's about the evolution of birds:

The early stages of the process through which birds evolved from dinosaurs was slow and gradual, and there was no single “missing link” separating the two different types of creatures, according to research published in Thursday’s edition of the journal Current Biology.

Lead author Dr. Stephen Brusatte, a paleontologist at the University of Edinburgh in Scotland, and his colleagues analyzed the anatomical make-up of more than 850 body features in 150 extinct species in order to map the evolutionary journey from meat-eating dinosaurs to ancient birds. Based on the fossil records, they found that the emergence of birds took place bit-by-bit over the course of 150 million years.

That's something I've noticed in reading about dinosaurs -- as we've discovered more about them, it's become apparent that things like feathers were around long before there were birds to wear them. It makes sense that other characteristics would pop up along the line until you had something approaching bird-hood.

And then things started happening really fast:

“There was no moment in time when a dinosaur became a bird, and there is no single missing link between them,” Dr. Brusatte said in a statement. “What we think of as the classic bird skeleton was pieced together gradually over tens of millions of years. Once it came together fully, it unlocked great evolutionary potential that allowed birds to evolve at a super-charged rate.”

And so we now have everything from sparrows to ostriches.

I have to admit of a certain fondness for sparrows. They're just always so busy.