Comments on: New study shows that gators are one-way breathers too.

By: Michael O. Erickson

Michael O. Erickson — Sat, 30 Jan 2010 00:57:59 +0000

Well, for one, not everyone is convinced that crocodilians are only secondarily ectothermic. The idea is still highly controversial, though it may not seem so as the proponents of the hypothesis have been more vocal than the detractors.

Also, despite what many have claimed, feathers do not necessarily support full-blown endothermy, as Jura has touched upon here:

http://reptilis.net/2009/04/13/a-critical-evalution-of-tianyulong-confiusci-part-3-plucking-at-the-idea-of-feathered-dinosaurs/

By: JW

JW — Thu, 28 Jan 2010 22:53:00 +0000

As a comment to the comments (the post is very nice):
Actually, on the contrary, what this paper does is further support the possibility that unidirectional lungs DO support endothermy, and in fact like many features of crocodylian anatomy, suggests that modern crocs simply “downgraded” their physiology to match their lifestyle. Aside from that, there are so many lines of evidence that support dinosaur endothermy, that the unidirectional lung is by no means necessary (e.g. feathers).

By: Louis Bérubé

Louis Bérubé — Thu, 28 Jan 2010 03:24:22 +0000

Speaking of endothermy…

If it took us this long to figure out gator breathing direction when living specimens are all around us, what are the odds of actually coming to any solid conclusion about something as complex as dinosaur metabolism?

Good writeup, Jura.

By: Jura

Jura — Thu, 28 Jan 2010 00:28:42 +0000

Thanks. I’ve always felt that the push to make dinosaurs “warm-blooded” was specifically to allow us to imagine them running around, taking care of their children, or getting into epic battles with each other. All traits that have generally been considered a hallmark of “warm-blooded” animals only. What I hope, is that data from Farmer, Sanders, Somma and others will help to remove this old stereotype of what “cold-blooded” animals can and cannot do. Who knows, there might even come a day when calling a dinosaur a “good reptile” is no longer considered an insult.

By: Michael O. Erickson

Michael O. Erickson — Wed, 27 Jan 2010 21:26:54 +0000

My thoughts: Farmer and Sanders’ work destroys the link between unidirectional air-flow and endothermy, and calls for people to quit throwing the presense of flow-through lungs and air-sacs in non-avian saurischians up in the faces of those such as yourself and myself*, who consider dinosaurs to have been ectothermic.**

Another excellent post, Jura!

*I was once an endothermy advocate. No so anymore.

**Or, who quite simply fail to be swayed by the purported evidence “clearly” favoring endothermy and prefer to view the evidence as equivocal.