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Re: Archie bones

In a message dated 96-02-02 14:51:33 EST, ornstn@inforamp.net (Ronald
Orenstein) writes:

>My God, you weren't kidding!  Okay, let's get this straight:  I am not aware
>of one single feature that Archaeopteryx shares with cormorants and anhingas
>(and I am talking about convergences here, obviously - certainly nobody is
>implying that Archie is a cormorant) that can be interpreted as an
>adaptation for diving.  In fact, though Archie is arguably a pretty
>specialized dinosaur, it strikes me as a very generalized bird.
>If you are under the impression that cormorants and anhingas do not show
>skeletal specializations for diving and associated prey capture, you are
>incorrect.  See Johnsgard, "Cormorants, Darters and Pelicans of the World",
>pp. 34-41, for a summary of these.  They include: elongation of the
>postacetabular portion of the pelvis (for attachment of musculature involved
>in foot-propelled diving); well-developed patella; adaptations of the
>cervical vertebrae for thrusting (especially in anhingas); a relatively
>sturdy ribcage (in cormorants) to withstand water pressures; etc.
>>Hey, there were lagoons a plenty in Bavaria of 145 Ma. Maybe some of those
>>_Archaeopteryx_ skeletons got there by drowning during dives. Wouldn't it
>>neat to find fish scales in the stomach of one of those specimens? Of
>>this still wouldn't prove they dived after the fish, only that they ate (or
>>scavenged) them.
>As you said yourself in relation to proterosuchids, the fact that the
>specimens ended up under water proves nothing, and I know of no feature in
>Archie that suggests aquatic feeding habits.  As I suggested in an earlier
>post, they could have nested on lake islets to avoid predators and flown
>regularly over water to get to feeding grounds (as some nutmeg pigeons do

Well, there's one neat idea shot down in flames, eh? So was Larry Martin
incorrect about there being no hollow bones in _Archaeopteryx_? And if this
were the case, namely, that _Archaeopteryx_ bones were solid, it would have
to be a reversal, since many theropod bones were hollow, even pneumatic.
So--why the reversal, if indeed it happened?