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Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)



> > >> The fossil record points in the opposite
> > direction: the
> > >> bats still haven't got the idea of
> soaring,
> > and the birds
> > >> seem to only have evolved it after the
> Mesozoic
> > was
> > >> over. 

Again, forgive me to nitpick (especially as it's really not important, as there 
seem to have not been Early Cretaceous soarers): the fossil records supports a 
Maastrichtian-ish origin of soaring. When an avian fossil record of some 
density sets in again in the Pg, taxa that for all we can say must have been 
very good (pelagic) soarers actually abound. And I don't think soaring ability 
dropped out of the skies in an instant, particularly not over a bolide-blasted 
Early Paleocene landscape - given the fact that there is good indication, 
inference or even evidence of above-average soaring capability existing in 
*diverse* lineages (pelagornithids, tubenoses, ?Lari, phalacrocoracids) by the 
end-Paleocene.

For the fossil record to support a post-K origin of soaring in Neornithes, it 
would be necessary for at least one structural homoplasy, probably at least 4 
(around which we won't get, because the opposite would require even more) to 
evolve, out of non-specifically-adapted flappers/gliders/pick-your-poisons in 
less than 10 Ma, probably less than 5. 

Cf. Hope's review in "Mesozoic Birds". Any wing bone that resembles that of, 
say, a tubenose more than anything else was either from a tubenose (in which at 
least basic pelagic soaring is plesiomorphic), or from a pelagic soarer 
incertae sedis.


Regards,

Eike

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