16 SEP 2011 by ideonexus
Birds to Reptiles
Because reptiles appear in the fossil record before birds, we can guess
that the common ancestor of birds and reptiles was an ancient reptile,
and would have looked like one. We now know that this common ancestor
was a dinosaur. Its overall appearance would give few clues that it was
indeed a “missing link”—that one lineage of descendants would later give
rise to all modern birds, and the other to more dinosaurs. Truly birdlike
traits, such as wings and a large breastbone for anchoring ...Folksonomies: evolution
Folksonomies: evolution
Birds and reptiles share many resemblances, meaning they have a common ancestor, which is dinosaurs.
19 MAY 2011 by ideonexus
Species Divisions are Complicated
Zoologists have traditionally divided the vertebrates into classes: major divisions with
names like mammals, birds, reptiles and amphibians. Some zoologists, called 'cladists',* insist that a
proper class must consist of animals all of whom share a common ancestor which belonged to that
class and which has no descendants outside that group. The birds would be an example of a good
class. All birds are descended from a single ancestor that would also have been called a bird and
would have sha...The ancestors are birds are reptiles, but in the fossil record where do we draw the line between them?