Comments on: Resizing Amphicoelias

By: Gabriel Garcia

Gabriel Garcia — Sun, 14 Jun 2009 22:57:04 +0000

Oops, I went to say Argentinosaurus.

By: Gabriel Garcia

Gabriel Garcia — Sun, 14 Jun 2009 22:56:05 +0000

This is not the largest dinosaur! Argentinoasurus is, it weighed about 90 to 115 tons, but the blue whale can weigh 209 tons.

By: Whitney Colbert

Whitney Colbert — Mon, 13 Oct 2008 22:57:44 +0000

I have serious doubts as to the size estimate, given that we don’t really know, and never will know, barring a complete specimen (highly unlikely to ever occur given the enormity of the animal even at minimum, the area of ground needed to be intact to preserve it, and the fact that fully articulated skeletons are almost non-existent in the fossil record)…the SHAPE, in life, of the animal. It could’ve had a highly tapered tail, neck, or both- which could make it yards and yards shorter than estimated.
Given the size of the known specimens, however, I’d caution a guess that it would likely have at least rivaled the blue whale in weight and certainly length would have likely been in excess of 120 feet in larger individuals.
Not that we should rule out a 190 foot animal- not too long ago, the top minds in science thought it IMPOSSIBLE for an animal the size of apatosaurus to support it’s (comparatively tiny) bulk without the aid of water, and couldn’t FATHOM and animal the size of argentinosaurus and the like. Yet they’re known to have existed, walked on land, held their tails above the ground, and even traveled together.

By: Sarda Sahney

Sarda Sahney — Tue, 20 Mar 2007 21:25:39 +0000

Sorry to double post, but would you mind if I put this image on my blog with a link back to yours?

By: Sarda Sahney

Sarda Sahney — Tue, 20 Mar 2007 21:24:48 +0000

Amazing! I wonder how much it ate? How fast it lost heat? My nephew would probably ask how much gas it produced!

By: dinogami (Jerry D. Harris)

dinogami (Jerry D. Harris) — Thu, 01 Feb 2007 23:33:58 +0000

Yup…the paper in the new NMMNH&S Bulletin was most of what I was talking about last year…one last little tidbit will show up at SVP in 2008 (yes, 08), and that will make all the drawings pale in comparison!

As for how A. fragillimus could get enough food with a gigantic stomach, the answer lies in a relationship between gut size and nutrition extraction from plant matter. Basically, the longer the food sits there, the more it is broken down and the more nutrients are extracted from it, and the larger the stomach, the longer the food sits there. Thus, sauropods seem to have been able to get more from less food than most herbivores may have. This, and other related aspects of sauropod paleobiology, were also covered recently in:

Engelmann, G.F., Chure, D.J., and Fiorillo, A.R. 2004. The implications of a dry climate for the paleoecology of the fauna of the Upper Jurassic Morrison Formation; pp. 297-308 in Turner, C.E., Peterson, F., and Dunagan, S.P. (eds.), Reconstruction of the Extinct Ecosystem of the Upper Jurassic Morrison Formation. Sedimentary Geology 167.

By: wolfwalker

wolfwalker — Fri, 19 Jan 2007 01:23:09 +0000

_Fifty-eight meters long_?

That’s one honkin’ HUGE animal!

And there’s no reason to think the vertebra that Cope found was from a maximum-size individual. Others of the species might have gotten even larger. So much for the blue whale as “the largest animal that ever lived on Earth.”

One other line jumped out at me from the abstract of Carpenter’s paper. Carpenter wrote: “One possible cause for large body size in sauropods, based on studies of extant mammalian megaherbivores, may be due to increased gut size for more efficient digestion of low quality browse by hindgut fermentation.”

Later in the paper he says that diplodocids achieved larger gut size by simply enlarging the entire body, leading to the monstrous sizes achieved by “Seismosaurus” and _Amphicoelias fragillimus_. Doesn’t this imply that these dinosaurs gained at least enough additional nutrition from the increased gut capacity to feed their increased mass? _A. fragillimus_ is double the length of _Diplodocus carnegei_, which implies eight times the mass, which in turn implies eight times the need for feed. Does this make sense in light of the known or calculated values of the nutritive value for Late Jurassic plants?

By: Halbred

Halbred — Mon, 15 Jan 2007 21:30:47 +0000

That’s insane. Questions immediately pop into my head. How fast did it grow? How could it have possibly been endothermic at that size? How could it even stand, given its significant tonnage?