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Re: SVP Details II



Mickey wrote: "Hartman concludes that lengthening of primary and caudal feathers in maniraptorans provided pitch control and stability to short duration leaps on to prey (as has been hypothesized for dromaeosaurids). He thinks this shows that wing and caudal feathers may have evolved in a terrestrial context."

First of all, I want to thank Mickey for taking the time to provide a SVP summary to the list. Since he was covering such a large quantity of talks, this is certaainly not meant as a criticism of his explanation of my presentation. I did, however, want to clarify the logic in my arguement.
The anti-bird/dino types have often cited hypothetical models of evolutionary pathways to flight that state in-effect that it is impossible for flight to have evolved from terrestrial cursors. They also argue that known theropods are not arboreal, ergo birds could not have evolved from theropods.
See my other post, or Gishlick's analysis, for evidence on why theropods could not have been arboreal scansors. It may well be that we will find arboreal theropods (yes, I know of the long fingered critter, and no, it is NOT arboreal, unless it brachiates). My main thesis was that there is no barrier to evolving flight within a terrestrial context, so other hypothetical models should not be used to critique phylogenetic analyses unless their is unambiguous fossil evidence for a particular mode of evolving flight.
In fact, my talk did not actually deal with the change-over to flight, but rather with pre-adaption to flight by evolving aerodynaimc surfaces. The model does in fact cover this change-over, but my talk was long enough as it was, so everyone will just have to wait for it to be published.
After highlighting some functional aspects of my aerodynamic model, I presented a couple converging lines of evidence that suggest that this _may_ have been the evolutionary pathway that maniraptorans took on the way to flight.
I had also made some phylogeneticly based predictions on future finds as well as unstudied anatomy on known taxa, but alas, I had already taxed the time my excellent moderators could alot me, and I had to skip this portion.
Until these predictions are published and there has been time for other workers to confirm whether any of the predictions are accurate, I will not claim that birds leanred to fly "from the ground up." I do hope, however, to counter the use of other models of flight evolution to critique the excellent phylogenetic analyses currently be done.


That's it, thanks,

Scott
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