Comments for Reptilian Rants

Comment on Mechanics of bipedalism suggest dinosaurs had to be warm-blooded. Or: Why the aerobic capacity model needs to be retired. by John Hutchinson

John Hutchinson — Mon, 01 Mar 2010 19:38:31 +0000

Jura kindly posted a summary of his comments/queries for us on PLoS ONE and we responded:
http://2ilz.sl.pt

Comment on Bone histology says ectothermic goats, but does it? by Are Mammals Cold-Blooded? | CRAZY CREATURES

Are Mammals Cold-Blooded? | CRAZY CREATURES — Tue, 16 Feb 2010 17:24:26 +0000

[...] Researchers have found one mammal that is believed to exhibit ectothermic characteristics, a sheep like creature that went extinct about 5000 years ago. Bones of the Myotragus Balearicus show that its growth rate was related to the food available, similar to reptiles, and not continuous as in warm blooded mammals. However, this study probably doesn’t show enough evidence to class this animal as cold-blooded. A good counter argument can be found here. [...]

Comment on Dinosaur George can bite me! by Send George Home...

Send George Home... — Sat, 13 Feb 2010 18:35:42 +0000

“Dinosaur” George is nothing but a blowhard. I have seen all of the episodes and wondered where they got this guy so I looked him up and he is “self-taught”. Meaning has no education in these fields and he certainly is no scientist. He is a self promoter. They show would have been a lot more enjoyable without him constantly telling us things that have never been proven. Having said that, I did enjoy the show. It is great entertainment. But it is not “education”. Go to school “Dinosaur” George…….

Comment 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/

Comment on New study shows that gators are one-way breathers too. 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).

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

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

Comment on The old grey sauropod just ain’t what she used to be. by Jura

Jura — Wed, 27 Jan 2010 23:51:20 +0000

Yep. If I remember correctly too, the “brontosaurus” in the picture was heading back to her swampy habitat after coming on land to lay her eggs. My how the times have changed. : )

Comment on The old grey sauropod just ain’t what she used to be. by Greg Withnail

Greg Withnail — Wed, 27 Jan 2010 23:22:24 +0000

I had the book that the top illustration is from. Mine was simply called “Dinosaurs: Mighty Monsters of the Past.” I’ve been hunting for a copy for years now as the pictures were so fantastic. I remember the story that accompanied the illustration above. It told of an Allosaurus attacking a Brontosaurus, while Camptosaurus looked on. I always remember that the Allosaurus sunk his teeth into Brontosaurus’s “meaty shoulder” – made it sound quite tasty! lol

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