Re: GOULD ON FLIGHTLESS THEROPODS

[chris brochu <cbrochu@fieldmuseum.org>]

Sadly, I have to agree with everything Darren said about Gould's article.
Gould has had some magnificent essays over the years; this was not one of
them.



chris




>On SJ Gould's article in the Nov' _Natural History_ (vol. 109, ish. 9),
>George wrote...
>
>> OK, I'll bite. What point did Gould miss? I thought the article was
>> interesting, if rather ironically: It's one of the first articles I've
>> seen that hints that BCF is how dinosaurologists had theropod-bird
>> relations all along.
>
>This may be my interpretationary bias but.... Gould makes out that
>people are up in arms about the Jones et al. (2000) study BECAUSE
>Jones et al. are claiming that _Caudipteryx_ is a secondarily flightless
>bird. Gould expresses his bemusement at lack of acceptance of this
>relatively simple concept, and bemoans the fact that most workers
>express scepticism. However, his approach lacks some fundamental
>criticism.
>
>(1) As was discussed way back when the paper came out, inherent to
>the Jones et al. study is the implication that _Caudipteryx_ is nothing
>to do with coelurosaurian theropods. As Jim F argued, this is not the
>main point of the paper, but is IS inherent to the study.
>
>(2) The big deal about _Caudipteryx_ - and the reason that derivation
>of _Caudipteryx_ from a flighted ancestor is regarded as so
>controversial by many workers - is that it is probably outside of the
>clade that includes _Archaeopteryx_ and other birds. Gould did not
>(apparently) recognise this and accepts the purported avian status of
>_Caudipteryx_ as provided by Jones et al.
>
>I'm also troubled by Gould's discussion about problems with 'living
>dinosaurs'. He says that we don't go round calling mammals living
>_Dimetrodons_. This is hardly the same and, in fact, you could call
>mammals living eupelycosaurs if you wanted to. What Gould says
>about basal synapsids is pretty wrong so far as I can tell - what is this
>about 'three major subgroups, only two bearing sails on their backs.
>Mammals probably evolved as a branch of the third, sailless group'?? I
>presume his 'sailless group' refers to the old concept of
>Ophiacodontia? (or is he talking about caseasaurs?) The two sailed
>groups, sphenacodontids and edaphosaurids, actually branch off closer
>to the Mammalia than these and, in any case, basal members of these
>two groups were apparently sailless (I'm unaware of any sailless
>edaphosaurid but the sphenacodontid _Sphenacodon_ is sailless).
>
>Gould argues that we don't call poodles wolves. I disagree... dogs are
>wolves and, if you're being pedantic you certainly ARE right in calling
>your poodle a wolf.
>
>As an aside, the article is historically interesting in that Gould recounts
>Greg Paul's argument about derivation of bird-like flightless theropods
>from flighted ancestors, yet without reference to Greg or to this
>hypothesis. In 1988 GSP suggested that a flightless descendant of an
>_Archaeopteryx_-like ancestor would not be as strongly modified for
>flight as advanced birds, would have big hand claws, long fingers etc
>and would thus make a 'better' dinosaur than, say, a flightless
>palaeognath. Gould presents an identical argument.
>
>I don't know if this is just me being stupid, but I should like to say that
>the article is written in indecipherable riddles - it is absolutely stacked
>full of obscure references that went completely over my head. I've
>never really noticed this in Gould's writing before.
>
>There is one nice line though...
>
>"... our latter-day tyrannosaurs in the trees continually chirp the New
>Age message of _Jurassic Park_: life finds a way"
>
>DARREN NAISH
>PALAEOBIOLOGY RESEARCH GROUP
>School of Earth, Environmental & Physical Sciences
>UNIVERSITY OF PORTSMOUTH
>Burnaby Building
>Burnaby Road                           email: darren.naish@port.ac.uk
>Portsmouth UK                          tel (mobile): 0776 1372651
>P01 3QL                                tel (office): 023 92842244
>                                       tel (home): 023 80446718


------------------------
Christopher A. Brochu
Department of Geology
Field Museum
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Chicago, IL 60605

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