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Re: Vegavis gen. nov. - new anseriform in today's Nature



----- Original Message -----
From: "John Bois" <jbois@umd5.umd.edu>
Sent: Friday, January 21, 2005 2:13 AM

Feduccia's response to the K duck is that it couldn't be a duck because
the extinctions were too devastating for ducks to survive!

Feduccia is supposed to be an expert on birds, not on impacts. Is there really already a published remark by him on *Vegavis*?


At the instant the asteroid hit there were sure many small juvenile
non-avian dinosaurs, surely with adaptation for hiding.  It's as if the
non-avian dinosaurs were freaks, without instincts for seeking cover etc.
Given the "lawn-mower" ecology, juvenile dino babies would have had
similar access to protection as birds.

Sure, but that's not going to help them during the fungal spike, and not during the fern spike and the following climatic fluctuations either.


- Flight. Means the ability to cheaply cover vast distances in search of
food, mates, nesting sites and whatnot. This in turn means that much fewer
individuals per continent need to survive to continue the species.

So, now you're saying na dinosaurs survived in some locations but couldn't find mates because they couldn't fly? This _is_ becoming less extreme!

Slowly it's dawning on me what you seem to think I thought. I never said or meant that the impact DIRECTLY killed every single individual non-neornithean dinosaur, if that's what you mean. I say that the impact decimated their populations below the point of sustainability.


- Ability to live off seeds (Galliformes, Palaeognathae).

...and who knows how many non-avian dinosaurs.

Not any known one.

- Ability to live off insects (Galliformes, Palaeognathae, who knows what
else).

Ditto...

Insects alone can't have been enough for any known Late Cretaceous nonavian dinosaur.


check the diet of juvenile crocs.

Crocs survived...

Evidence for Cretaceous members of Neoaves -- a huge clade! -- is still
quite poor. Besides... the more species we find that are _not_ ancestral to
extant species, the _more_ support there is for an instantaneous,
all-encompassing catastrophe... and this, too, is going on now, partly by
new finds (the toothed bird of Maastricht, *Limenavis*...), partly by
revisions of known specimens (*Iaceornis*, probably *Polarornis* and
*Neogaeornis*...).

OK...so now you need another mechanism, one that kills off the old birds and spares the new.

Wrong. I need a combination (!) of mechanisms that kills off the old birds and spares a few (!!!) of the new ones -- perhaps so few that dumb luck alone (!) suffices as the explanation.


This is sounding more and more like angels on pinheads.

You wish. :-)