Thunder beasts of New York

I may as well finish what I started. Inspired by the two recent brontothere articles, Dan Varner and Mike P. Taylor were kind enough to supply the pictures you see here. Both feature Megacerops specimens displayed at the American Museum of Natural History in New York.


This classic photo shows Erwin S. Christman (1885-1921) working on the life-sized Megacerops head that he and William K. Gregory created for what's now the Lila Acheson Wallace Wing of Mammals and Their Extinct Relatives at the AMNH [we looked briefly at Christman's work on theropod dinosaurs back here]. At the time (c. 1911), this head was labelled as that of Brontotherium platyceras*, a name now included in the synonymy of Megacerops coloradensis (Mihlbachler in Janis et al. 2008). While many M. coloradensis individuals have paired horns that look like blunt, parallel knobs, individuals once labelled as Brontotherium tend to have Y-shaped horns that are flattened from front to back. These are most likely big, old males.

* It started out as Menodus platyceras Scott & Osborn, 1887 and, over the years, was also termed Megacerops platyceras.

Thanks to Henry Osborn's influential work on the group, brontotheres became intimately associated with the AMNH. In 1929, Osborn published a two-volume, 953 page monograph on the group, proposing numerous new genera and species (Osborn 1929). Christman's illustrations decorated the work, as did those of Charles Knight and Lindsey Morris Sterling. Osborn's approach to brontothere taxonomy proved problematic and he's been criticised for being a 'hyper-splitter' (Debus & Debus 2002). Recent revisions have sunk the majority of these alleged taxa. George Simpson, also of the AMNH, was able to say in 1945 that Osborn had clearly been led astray by individual, sexual, ontogenetic and taphonomic variation, and he noted that 'subjective criteria have seemed to warrant placing every good specimen in a new species' (Simpson 1945, Wallace 1994).


This incredible skeleton, easily the best known brontothere specimen in the world, is AMNH 518, collected from White River, South Dakota, in 1892. You can gauge its size from the adjacent person, and note that Christman's 'Brontotherium' head is just making it into shot at the very top. Originally identified as Brontops robustus, AMNH 518 is also now included within Megacerops coloradensis. This specimen is particularly well known because it has an obvious rib trauma on its right hand side - a healed injury that has usually been regarded as resulting from intraspecific combat.

And there we have it, thanks to Dan and Mike for passing on the images. There are, of course, many other neat and striking brontothere images out there: Carl Buell's paintings and Frederick Blaschke's Field Museum diorama of 1931, among others, coming to mind. Hat tip to them all, for we must move on...

Refs - -

Debus, A. A. & Debus, D. E. 2002. Dinosaur Memories. iUniverse, Bloomington.

Janis, C. M., Hulbert, R. C. & Mihlbachler, M. C. 2008. Addendum. In Janis, C. M., Gunnell, G. F. & Uhen, M. D. (eds). Evolution of Tertiary Mammals of North America, Volume 2: Small Mammals, Xenarthrans, and Marine Mammals. Cambridge University Press (Cambridge), pp. 645-693.

Osborn, H. F. 1929. The titanotheres of ancient Wyoming, Dakota, and Nebraska (two volumes). United States Geological Survey Monographs 55, 1-953.

Simpson, G. G. 1945. The principles of classification and a classification of mammals. Bulletin of the American Museum of Natural History 85, 1-350.

Wallace, J. 1994. The American Museum of Natural History Book of Dinosaurs and Other Ancient Creatures. Prion, London.


More like this

I am in awe of that sculpture. Looks like they just lobbed the living animal's head right off. Are there any good color photos of it?

Our local museum has a diorama with two adult megacerops and a juvenile - can send you a photo of it sometime if you want it for a post.

By Epinephrine (not verified) on 28 Mar 2009 #permalink

One of my favorite alcoves in the "Mammals and their extinct relatives" section of the 4th floor of the AMNH! That is, of course, the broken-ribbed Brontothere I mentioned in my comment to the previous Brontothere post. (((The woman in the photo, b.t.w., is standing with her back to one of the other fascinating, and emotionally loaded, Perissodactyl exhibits: a mare (of some 3-toed late Miocene species) that died, probably of resulting infection, after a breech presentation of a foal: the foal's bones are preserved in place. Viviparity, in species with large, precocial, young, means walking on the edge of catastrophe with each pregnancy.)))

One loss when the AMNH re-worked its Paleontological halls about a decade ago: the skeletal mount of Phenacodus is no longer on display. There is a skeleton (not sure how much is original bone) of "Hyracotherium" with a bunch of later horses, and it would be nice to be able to compare it with Phenacodus.

By Allen Hazen (not verified) on 28 Mar 2009 #permalink

Just noticed: in the sculpture of what's-is-name, the upper lip is shown as slightly pointed: a bit like that of a Black Rhinoceros, though perhaps not as pronounced. Given that Brontotheres are thought to have been browsers and not grazers, this is a plausible touch.

By Allen Hazen (not verified) on 28 Mar 2009 #permalink

Allen: I recall reading a study on brontothere tooth microwear which showed that they were exclusively folivorous (with there being no evidence for frugivory, IIRC). And, as mentioned previously, the strongly reduced morphology of the incisors indicates the presence of a black rhino-like prehensile upper lip. The microwear study I have in mind might be...

Mihlbachler, M. C. & Solounias, N. 2002. Body size, dental microwear and brontothere diets through the Eocene. Journal of Vertebrate Paleontology 22 (suppl. 3), 88A.


There are, of course, many other neat and striking brontothere images out there: Carl Buell's paintings and Frederick Blaschke's Field Museum diorama of 1931, among others, coming to mind.

With brontothere images, there seems to be something of a tradition of painting an active volcano in the background of the landscape. Rudolph Zallinger did that in his The Age of Mammals mural, and ZdenÄk Burian did so at least twice. Does anyone remember the book Album of Prehistoric Animals by Tom McGowen and Rod Ruth, from the 70ies? It has a dramatic illustration (by Ruth) of brontotheres fleeing from a volcano eruption, while thunder and lightning fill the sky (IIRC). Thunder beasts indeed; I found that image seriously awesome as a child.

Thanks for reference. I will try to get it (JVP in electronic form my library has, but I'm not sure about supplements).

By Allen Hazen (not verified) on 29 Mar 2009 #permalink

I think i heard of a criptid from some where in north america that could probably be a living bronto, has eny one else heard of it?

By zach hawkins (not verified) on 29 Mar 2009 #permalink


Allen: I recall reading a study on brontothere tooth microwear which showed that they were exclusively folivorous (with there being no evidence for frugivory, IIRC).

Another paper reporting evidence for folivory in Megacerops (=Brontops) is:

Zanazzi, A. & Kohn, M.J. 2008. Ecology and physiology of White River mammals based on stable isotope ratios of teeth. Palaeogeography, Palaeoclimatology, Palaeoecology 257, 22-37.

It seems that brontotheres are always depicted as grey rhinoceri with funky horns. But for al we know, they may have been hairy (or at least furry), or brown, or black, right? Are there any reconstructions that stray from that beaten path?

By Kilian Hekhuis (not verified) on 30 Mar 2009 #permalink

Kilian --

It may be too small for you to have picked up on it, but the Zdenek Burian reconstruction that is at the top of Darren's previous post shows Brontotherium ... er, Megacerops as a dark-furred, slighly shaggy creature.

You can see a little of the furriness here: -- but in this case, the image is a bit too dark to see it to full effect.

(To be continued, because of SB's "one URL per comment" anti-spam rule.)

By Stevo Darkly (not verified) on 30 Mar 2009 #permalink

Charles Knight also did a brontothere reconstruction that was pretty furry -- this pencil sketch shows fur on the legs, and a rather shaggy mane on the neck and back:

(The color version of this also shows the shaggy mane quite clearly, but the fur on the limbs is harder to see.)

I also once found a restoration on the Web that depicted a brontothere mother and calf in a snowstorn -- I'm pretty shure they were depicted as furred. And dark gray or black in color. Can't remember where I found it or who did it -- you've caught me right before I need to go into a meeting, so maybe later.

By Stevo Darkly (not verified) on 30 Mar 2009 #permalink

Aha! Found that "black brontotheres in the snow" image.

I can't link to it directly, but go to --> "Paleo Art" --> "Ancient Mammals."

The image is rather small, though. I've tried blowing it up, but I can't tell whether the artist intended to depict the brontotheres as bare-skinned (brr!) or as having short, dense fur, like a deer.

By Stevo Darkly (not verified) on 30 Mar 2009 #permalink

Dartian -- Yes, I have Album of Prehistoric Animals. I read it a lot as a kid -- that was the first place I heard of quite a few of the weird prehistoric mammals.

By William Miller (not verified) on 31 Mar 2009 #permalink

Here's yet another brontothere image with a smoldering volcano in the horizon. I don't know who the artist is; does anyone? I'm almost sure that it's not Burian, although there's definitely a Burian-feel to the picture.

I really love this Megacerops head. I have once found a photo of the painted original, but it is really interesting to see it in the working porcess. The artistic level in which this wonderful life-like head was sculpted is really awesome. I suppose the head on the old photo is actually not the original, but an oil-clay model which was later casted in gypsum or another material. It looks really more life-like than many stuffed rhinos, and I would really love to have such a trophy-head over my bed or over the chimney. Sadly I have only my Megalania trophy head there...