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Re: Missing link feather fossils



Speaking of storkish critters, I suppose you all have heard of the recent
trade agreement between South Africa, Tibet, and the Netherlands, swapping
cattle for birds, and known as the Gnu yak stork exchange...
(he dodges stones)
Scott Perry
----- Original Message ----- 
From: "evelyn sobielski" <koreke77@yahoo.de>
To: <dinosaur@usc.edu>
Sent: Monday, February 25, 2008 9:33 AM
Subject: Re: Missing link feather fossils


>
> > structure? I wonder how they compare to the feathers
> > of ratites.
>
> Many ratite feathers have an aftershaft, that is, they
> have a small secondary feather attached to the bottom
> part. But some don't. Still, it would be worthwhile to
> compare them to these, as well as to other Cretaceous
> non-pennaceous feathers.
>
> It is almost certainly impossible tha they are ratite
> feathers though. Finding a ratite from there and then
> is almost as unlikely as finding a tarsometatarsus of
> a passeriform bird in the Mesozoic (the latter is if
> the present consensus is any good about impossible.
> The former cannot be ruled out but is highly, highly
> unlikely).
>
> The St Bathan's fauna (Journal of Systematic
> Palaeontology 5 (1): 1&#8211;39
> doi:10.1017/S1477201906001957) includes what seems to
> be moa remains, but it is Early/Mid-Miocene. This ties
> in with ostrich fossils and _Emuarius_ suiggesting
> that at the end of the Paleogene, there were ratites
> was we know them today, both by lineage and by
> morphology.
>
> _Diogenornis_ is the only (and tentative) indication
> at present that the ratite morphotype evolved in the
> Paleogene, possibly even the latest Cretaceous.
>
> But all these are southern hemisphere finds. The
> northern hemisphere apparently had other giant birds
> in the Paleogene (diatrymas and _Eremopezus_ for
> example - the latter might have been a superficially
> ostrich-like storkish critter, perhaps). Laurasian
> ratites seem to have been rather tinamou-like til
> ostriches arrived in the Neogene (not sure, but it's
> the most satisfying hypothesis).
>
> Given that diatrymas are generally held to be
> Galloanseres nowadays, they are a possible candidate.
> 100 Ma seems a bit much though; all we *can* say is
> that Gastornithiformes must have been a distinct
> lineage about 70 mya (qua _Vegavis_), but the present
> scenario would make it very unlikely that they were
> distinct *and* had arrived at their morphotype 100 mya
> already.
>
> _Gargantuavis_ is sufficiently close in time, place
> and lineage to make an older relative of it the most
> promising *avian* candidate. Its lineage is unknown
> but it seems not to have been a modern bird (in the
> strict sense, i.e. Neornithes). If this is correct, it
> makes for a comfortable to very comfortable fit
> (depending on whether it was enantiornithine or much
> closer to modern birds).
>
> IONO whether the supposed diatryma feathers were
> verified. At least part of it seems to have been plant
> fibers.
>
>
> Regards,
>
> Eike
>
>
>
>
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