into the air (Introduction)
by David Turell 
, Wednesday, October 24, 2012, 20:43 (5010 days ago)
Birds came from dinosaurs, who had feathers. but how to get airborne? No one yet knows. Here is a possibility:- http://blogs.scientificamerican.com/observations/2012/10/23/reanalysis-of-four-winged-d...