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RE: flight beginnings
They didn't stop using this argument until they became MANIACs.
Geist and Feduccia (2000) write- "Furthermore, the non-aerodynamic,
stereotypically deep, laterally-compressed body shape of theropods,
characterized by the relatively long, narrow, vertical to subvertical pubes,
and the long, stiffened, counterbalancing tail typical of derived
maniraptorans, is antithetical to arboreality."
Feduccia (2001) wrote- "As a final note, the entire bauplan of early (late
Triassic) theropods is exactly the opposite of what one would desire for the
origin of flight. Theropods such as Herrerasaurus, Syntarsus and Coelophysis
are typical, and exhibit the typical theropod body plan, with a laterally
Then in 2002, Feduccia suddenly places maniraptorans in Aves, destroying almost
all of his previous arguments, including this one.
References- Geist and Feduccia, 2000. Gravity defying behaviors: Identifying
models for protoaves. American Zoologist. 40(4), 664-675.
Feduccia, 2001. The problem of bird origins and early avian evolution. Journal
fur Ornithologie. 142, 139-147.
> Date: Tue, 24 Mar 2015 13:49:19 -0600
> From: firstname.lastname@example.org
> To: email@example.com; firstname.lastname@example.org
> Subject: RE: flight beginnings
> I'd like to add to that if I may.
> Larry Martin some time back in the [late 70s ??], once postulated that
> certain pseudosuchians had a body plan that made them more aerodynamic
> than early theropods because of the positioning of the downward projecting
> pubes in these early dinosaurs. Theropods were just not aerodynamic enough
> [compared to pseudosuchians].
> My thoughts at the time were that this actually helped theropods in the 1st
> The downward projecting pubes MAY have acted similarly as the anteroventrally
> placed "training" wheels on a kids bicycle. The "onboard computer" in both
> was not highly developed. Theropods and little kids had the added advantage of
> "trainers" until they w
> Martin must have figured this out because I never heard him ever raise this
> again. But .. isn't that supposed to be how science works ?? You attempt to
> your hypothesis .. not hide it ??
> I'm being a little harsh here. Sorry.
>> Date: Tue, 24 Mar 2015 18:18:19 +1100
>> From: email@example.com
>> To: firstname.lastname@example.org
>> Subject: Re: flight beginnings
>> Check out Dyke et al. 2013. DOI: 10.1038/ncomms3489
>> I like the idea of gliding in terrestrial theropods that
>> opportunistically foraged in trees, and used aerial locomotion to
>> return to terra firma. No thrust needed, nor even an extensive glide
>> path. Just maneuverability and orientational control during the
>> descent. (No need for a perching foot either.)
>> It may not be a coincidence that in some of these maniraptorans the
>> proportions of the third toe are similar to those of the modern kakapo
>> (_Strigops_), a flightless ground-dwelling parrot that climbs tree
>> trunks and uses its wings to return to the ground.
>> On Tue, Mar 24, 2015 at 3:04 AM, Richard W. Travsky wrote:
>>> On 3/22/2015 10:25 PM, Tim Williams wrote:
>>>> My favored hypothesis is that the first birds (and their maniraptoran
>>>> kin) used their feathered forelimbs for control during brief descents,
>>>> rather than for ascents (which require thrust, as well as lift).
>>> Do you mean by providing a cushion of air?