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Re: OUR FRIEND, THE KIWI



Greg Paul wrote:

>Of course wingless kiwis have a theropod-like locomotary apparatus,
>suggesting that their locomotary energetics were similar. Kiwis have
>fur-like feathers similar to those reported on the Chinese theropod,
>suggesting a similar need to retain internally generated body heat.

<Snip>

And to continue the analogy further, Kiwis can lay a single egg up to 25%
of the body mass suggesting Tyrannosaurus eggs must have weighed in at
around 1.5 tonnes.

I really don't think that you are using suitable caution here in your
comparisons. Apart from scaling effects, there are details that you seem to
gloss-over. Eg: From what I have seen of the Chinese bird-dinosaur, there
is a single row of short, rounded projections along the back that could be
the imprints of feathers. Kiwis are covered in rather long, straggly
looking feathers of a different structure. The differences between the
structure and distribution of these structures suggests that they may have
well had different uses in the two animals. This sould be enough to shake
confidence in the argument that, because Sinsauropterx had feather-like
structures and Kiwis have feathers and because Kiwi feathers are used for
heat retention, then Sinsauropteryx must have been using them for the same
purpose. God forbid (an unusual term of phrase for an atheist) this can not
reasonably be used as a line of argument that all theropods were
warm-blooded!

While I do agree that some modern birds such as the kiwi do have many
structural similarities in their hind limb structure with those of
theropods, I urge a high degree of caution when trying to use such
similarities in the reconstruction of extinct animals.

Cheers, Paul


Dr Paul M.A. Willis
Consulting Vertebrate Palaeontologist
Quinkana Pty Ltd
pwillis@ozemail.com.au