John Leonard wrote:
>
> The case for birds evolving from a dinosaur lineage of velociraptor sort
> appears very strong, as I understand it, but opponents (such as Feduccia)
> point out that birds like Archaeopteryx are known from the mid Jurassic, and
> their supposed dinosaurs ancestor don't appear until the Cretaceous. In
> other words fossil evidence for birds can be found for periods 150 million
> years before their supposed ancestors are found in the fossil record!
The following page contains some useful information on the
relationships between birds and dinosaurs:
http://www.ucmp.berkeley.edu/diapsids/avians.html
The page responds to the age "problem" quite concisely:
"Some researchers have raised issues that may seem to make the
theropod origin of birds difficult to support, but these
difficulties are more illusory than substantial. One proposed
difficulty is the gap in the fossil record between the first
known bird (Late Jurassic) and the dromaeosaurs, probable sister
group of birds (Early Cretaceous). This overlooks the blatant
fact that other maniraptoran coelurosaurs, such as Ornitholestes,
Coelurus, and Compsognathus, are known from strata of Late Jurassic
age. If other maniraptorans were there, it logically follows that
the ancestors of dromaeosaurs were there. Fragmentary remains of
possible dromaeosaurs are also known from the Late Jurassic."
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Paul Taylor Veni, vidi, tici -
I came, I saw, I ticked.
Birding-Aus is on the Web at
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