[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Archaeopteryx or Velociraptor
Imagine that Velociraptor is a) nonavian (generally agreed on) and b)
secondarily flightless. In the absence of a volant outgroup to the
Velociraptor-Neornithe clade, no amount of phylogeny can ever hope to
demonstrate that it is secondarily flightless.
Imagine for a moment that the world is attempting to decieve us about
the true workings of evolution (paranoid, yes, but everything is so darn
complicated that sometimes it seems like a pretty good model...) and has
conspired to eliminate both
b) all fossils of volant birds from outside the neognath-paleognath split.
Pretty simply, you don't have a chance in heck of using a phylogenetic
bracketing to demonstrate secondary flightlessness in ratites.
It may simply be that, as in my speculative example, the current data
is such that no amount of phylogenization can ever resolve it.
this is possible, the data that would be necessary for me to accept
> this hypothesis is a phylogenetic analysis placing one or more of the
> typical "non-avian" theropods within a clade with known flying members.
> This has not yet been the result of theropod phylogenetic analyses.
> > If modern birds had not given up their teeth and hand claws during their
> >evolution, the predominant predator might still be very theropod-like.
> At various points in the Cenozoic, large predatory flightless bitds did
> become the local dominant predators.
> Thomas R. Holtz, Jr.
> Vertebrate Paleontologist Webpage: http://www.geol.umd.edu
> Dept. of Geology Email:email@example.com
> University of Maryland Phone:301-405-4084
> College Park, MD 20742 Fax: 301-314-9661