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
Missing Links Make Defining Species Possible
As we trace the ancestry of modern Homo sapiens backwards, there must come a time when
the difference from living people is sufficiently great to deserve a different specific name, say
Homo ergaster. Yet, every step of the way, individuals were presumably sufficiently similar to their
parents and their children to be placed in the same species. Now we go back further, tracing the
ancestry of Homo ergaster, and there must come a time when we reach individuals who are
sufficiently different fro...Without missing links, species would blur into each other.