I found this while "surfing" and thought it might be of interest in "the
Land of Parrots"
Anne
>
> An academic squabble over dead parrots has broken out in
> the pages of the science magazine Nature. Last year,
> Thomas
> Stidham of the University of California, Berkeley
> described
> in Nature a small piece of a fossil jawbone of what he
> claimed to have been from a parrot. The fossil would have
> supported a horny beak very like that seen in a
> present-day
> parrot, and had other features suggesting that its owner
> had
> once been of the psittacine persuasion.
>
> The surprise was the fossil's age -- 70 million years.
> This
> set feathers flying in the ornithological community,
> because
> it flew in the face of conventional wisdom that no
> parrots
> existed that could have perched on the shoulders of
> dinosaurs, way back in the Cretaceous period. Apart from
> a
> few seabirds, no representatives of any modern group of
> bird was thought to have appeared until after the
> dinosaurs
> had become extinct, 65 million years ago.
>
> When Stidham showed the fossil to other specialists, he
> met
> with opposition: people were quite prepared to believe
> that
> this fossil was of a parrot until he revealed its age, he
> recalled at a palaeontological conference last year.
> Nobody
> believed that a fossil parrot could be that old.
>
> Gareth Dyke of the University of Bristol, UK, and Gerald
> Mayr of the Forschungsinstitut Senckenberg,
> Frankfurt-am-Main, Germany, have studied the oldest
> fossil
> parrots generally recognized as such. These come from the
> Eocene epoch and are around 40 million years old. In a
> letter in the 27 May issue of Nature, they question
> whether
> Stidham's fossil could have come from a parrot. They
> point
> to features of the fossil which resemble features seen in
> certain theropod dinosaurs, as well as other birds.
>
> Stidham is robust in defence of his fossil's parentage:
> in a
> published response, he chides Dyke and Mayr for not
> coming up with a credible alternative identity for the
> fossil.
> Rather than pecking at individual features, says
> Stidham, his
> critics should come up with an idea of which animal --
> other
> than a parrot -- exhibits all the features shown by his
> fossil.
>
> But Stidham's language about the role of conventional
> wisdom is fighting talk indeed: "It seems less than
> defensible", he says, "to propose that we cannot have
> Cretaceous parrots because the oldest well preserved
> fossils
> known so far are Eocene." It is hard to argue with the
> logic
> of this bold statement.
>
> However, it could be that the flap will not die down
> until
> and unless somebody disinters more complete remains of a
> parrot from Cretaceous strata. Even though it is hard to
> imagine what else Stidham's fossil could have come from
> if
> not a parrot, it is a surprising fact that the curved
> parrot-like
> beak we think of as uniquely parrot-like is not found in
> all
> parrots: indeed, the Eocene specimens did not have
> 'parrot-like' beaks, and are recognized as parrots on the
> basis of skeletal features.
--
Anne & Roger A. Green
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