Daeodon shoshonensis

Click here to see the skeleton of Daeodon

Dinohyus or "terrible pig" is what this beast used to be known as, and it certainly must have had a terrible appearance. But is only distantly related to true pigs and hippos, all of which belong to the same suborder, Paleodonta.  Along with Archaeotherium it is a member of the now extinct Entelodontidae.

Daeodon lived during the lower Miocene of western North America about 18 million years ago. A part of the artiodactyl radiation that followed the rise of vast grasslands during this time. One location where numerous Daeodon's bones were found was at Agate Springs, in Sioux County Nebraska in the late19th Century. These were part of a massive bone bed, laid down in a stream deposit.  This location points towards the probability that these animals died in some sort of natural calamity, most likely a  drought. They may have crowded around the last pools in a drying river bed where they perished. The final result being their bones were eventually washed downstream and accumulated  in a river bend where they are found today.  Moropus is also found here

Daeodon was bison sized, standing about seven feet tall at the shoulder, with a head over one meter long. Click Here to see the skeleton. At first glance the massive skull is very reminiscent of a primitive predatory animal such as a Creodont,  with large canine tusks, sharp pre-molars and a long snout.  But on closer examination the bunodont  (low-crowned)  teeth, show characteristics that point to an omnivorous way of life.   Meat in the form of carrion may have been a very important element of its diet. Bones of Moropus have been found with tooth marks that match the teeth of Daeodon very well.  It was unlikely that Daeodon was an active hunter. Perhaps it ambushed the very young of the camel Oxydactylus or the rhino Menoceros when the parents' guard was down. But an animal as huge and odiferous as Daeodon must have been, probably did not make a living as a stealthy killer. 

An enormous saggital crest ran along the top of the skull of Daeodon, and there was large surface area on the mandible for the attachment of robust jaw operating muscles helped Daeodon crush into nuts, roots, carcasses, or each other. The skulls of all Entelodonts sport bony flanges on the malar bones. and  protuberances on the lower jaw.  These protrusions probably served a sexual recognition or group hierarchy function.

The limbs were surprisingly long and gracile and seem a little out of proportion with the heavily muscled body, but were obviously meant to propel Daeodon at a very respectable speed over good distances. The feet ended in two small-hoofed toes (didactyl ) which on the skeleton look a little small  to hold up such a huge beast.  Daeodon probably  had large hoofs and plantar pads on the feet to absorb shock and stabilize the animal as it moved. Fossilized tracks of Daeodon have been found in ancient mud at Agate Springs.

The physical damage found on many of the Daeodon bones, including many punctures and scrapes on the skull, seems to indicate that Daeodon probably fought amongst themselves during mating rituals, or over territory, or perhaps carcass rights. I can imagine them swinging their massive heads from side to side with mouths open, bellowing out some guttural sound, curling  back their lips and bearing the huge teeth and shoving with those powerful bodies.

The painting above captures a moment between two male Daeodon squaring off on the Miocene grassland  somewhere near Agate Springs. They roar a challenge at each other before coming together in clash of tusks and a cloud of dust. In the far background is the twin horned rhinoceros Menoceros arikarensis, whose bones are also found in abundance at Agate Springs.