Biologists follow 'fossilizable' clues to pinpoint when mammal, bird and dinosaur ancestors became athletes

Biologists follow 'fossilizable' clues to pinpoint when mammal, bird and dinosaur ancestors became athletes 12/30/2016 02:07 PM EST Biologists have established a "fossilizable" indicator of athleticism in the bones of extinct vertebrates. The study is the first to draw a link between RBC size and microscopic traces of blood vessels and bone cells inside the bone. They found that extinct mammal and bird relatives had smaller RBCs and were likely better athletes than earlier terrestrial vertebrates. The timing of RBC-size reduction coincided with Earth's greatest mass extinction event 252 million years ago. Full story at http://unews.utah.edu/biologists-follow-fossilizable-clues-to-pinpoint-when-mammal-bird-and-dinosaur-ancestors-became-athletes/ Source University of Utah This is an NSF News From the Field item.   Follow NSF:  This email was sent using GovDelivery, on behalf of: National Science Foundation Update · 4201 Wilson Boulevard · Arlington, VA 22230 · 703-292-5111