A radical shortening in the bony tails of birds that lived
over 100 million years ago freed the legs to evolve in new ways and enabled an
explosive radiation of early bird species, a new study shows.
A team composed of Wits Senior Researcher Dr Jonah Choiniere
and Dr Roger Benson of Oxford University’s Department of Earth Sciences
examined fossils of the earliest birds from the Cretaceous Period (145-66
million years ago). At that time primitive birds such as Confuciusornis had
already evolved powered flight while living alongside their dinosaur kin,
necessitating changes to their forelimbs. The team investigated how this new
aerial lifestyle related to changes in their hind limbs (legs).