Truly Terrifying Entelodonts

i-0a3dcca5b7df1140fbffe273e45b1a6d-display_osborn_dinohyus.jpg


The skeleton of Daeodon (Dinohyus), an entelodont.


There are few fossil mammals that are as scary-looking as entelodonts. Justifiably called "Hell Pigs" in the book Cruisin' the Fossil Freeway, the long, toothy skulls of entelodonts are certainly imposing. This extinct group of pig relatives didn't just look fierce, though; the construction of their jaws and taphonomic evidence suggests that they had a taste for flesh as well as for plant foods.

Although entelodonts were most likely omnivores, their skulls show a variety of features that seem to be convergent with carnivores, especially bone-crushers like spotted hyena (Crocuta crocuta). The skull is long with many sharp teeth, the battery of premolars in mature individuals often showing wear-patterns consistent with those seen in bone-crushing carnivores today, including broken teeth that show similarities to the broken teeth of living hyenas. The area of muscle attachment on the side of the skull is also quite large, and entelodonts like Daeodon (Dinohyus) and Archaeotherium (pictured below) probably had a very powerful bite. Indeed, compared to modern relatives like pigs and peccaries, entelodonts had very long, powerful jaws that could have made short work of whatever carcasses they came across (or perhaps even whatever they might be able to catch).

i-df54666a99635678cb7c31b2c51c32a0-archaeotheriumskull.jpg


The skull of Archaeotherium. From Joeckel 1990.


Figuring out the place of entelodonts in terms of paleoecology is difficult, though. There were a number of other large predators that lived alongside them, and while it is highly likely that they did scavenge carcasses just how significant carrion was to their diet is hard to determine. Wear patterns on the canines of some of the largest entelodonts don't appear to support the idea that they were active hunters (at least not very often), but whatever they were consuming their long row of premolars were likely very important in processing food.

How much entelodonts scavenged may be open for debate, but the fact that they did is supported by fossil evidence. The bones of herbivores that shared habitats with entelodonts have been found showing characteristic tooth marks on them, one of the most recent such traces being bite marks on the humerus and femur of a chalicothere from Miocene-age deposits in Wyoming (Hunt 2005). More impressive taphonomic traces include a pile of camel fossils, and the evidence seems to indicate that the camels were hunted down and torn apart by the entelodont Archaeotherium. I'm sure there are other fossils bearing entelodont tooth marks, but I have yet to come across a synthetic work on the meat-eating habits of the "pigs from Hell."

i-5a8c5889579b00265225baec3e6fb7dc-entelodontbitemark.jpg


A percussion fracture on the distal end of a chalicothere femur, most likely the result of entelodont scavenging. From Hunt 2005.


References;

Foss, S.E. (2007) "Family Entelodontidae." The Evolution of the Artiodactyls, pp. 120-129

Hunt, R.M. (2005) "An Early Miocene Dome-Skulled Chalicothere from the ''Arikaree'' Conglomerates of Darton: Calibrating the Ages of High Plains Paleovalleys Against Rocky Mountain Tectonism." American Museum Novitates. No. 3486, pp. 1-45

Joeckel, R.M. (1990) "A Functional Interpretation of the Masticatory System and Paleoecology of Entelodonts." Paleobiology, Vol. 16 (4), pp. 459-482.

More like this

Thanks for the link Raymond. I've only heard this site being alluded to and was unable to find a link (if I did I would have gone into a little more detail with what I wrote above).

Looking at the drawing of the Archaeotherium skull, I noticed that three upper incisors are visible: so the arrangement of the incisors has a significant fore-and-aft component. (With many mammals the incisors are more side-by-side, and they would at least overlap in side view.) Ditto for two lowers.

I have no idea (and, in the current state of knowledge about basal Artiodactyl phylogeny, I don't think this is ENTIRELY my fault) how closely related Entelodonts are to primitive Cetaceans, but this is at least a resemblance. Try showing this drawing to a bunch of friends and see how many you can convince that it's a "Zeuglodon."

By Allen Hazen (not verified) on 12 Apr 2008 #permalink

I have read that Dinohyus hollandi (meaning "Holland's terrible pig") was named after John Holland (whose refutation of the "sprawling sauropod" idea you recently mentioned) by someone who didn't like him. A bit like Mosasaurus copeanus Marsh (looks like a simple dedication, but can be interpreted as Cope-anus).

By Lars Dietz (not verified) on 13 Apr 2008 #permalink

Well, as a total anatomical ignoramus I'm wondering why the first few ribs are so tightly conjoined with the breastbone. This almost looks turtle-ish...

And hey, half-hog, half-hyena, runs like a racehorse and eats camels. Entelodonts sound more like some Mark Twain brag than an actual animal. I love 'em.

The photograph at the top of the article is orthogonal enough to be the basis of a decent reconstruction. (Although without some shots from other angles...) Anyway. Where did you get that photo?

With those jaws, they could easily be the bears of their time, eating just about anything. They could browse on plants, hunt their own food, and hog carcases.

Altın Ãilek sayesinde sabah ve akÅam yemeklerden yarım saat önce alınarak iÅtahınızı kapatmaya yardımcı olarak, yemek vakti geldiÄinde yemek yeme isteÄinizin azalmasında yardımcı olacaktır.

Looking at the drawing of the Archaeotherium skull, I noticed that three upper incisors are visible: so the arrangement of the incisors has a significant fore-and-aft component. (With many mammals the incisors are more side-by-side, and they would at least overlap in side view.) Ditto for two lowers.

iggered the succession of different forms (he did not advocate evolution nor did he support multiple creations, and he generally kept his religious beliefs out of his efforts to create a hard-nosed, syste