Those giant killer pigs from hell aren&rsquo;t pigs
 By Darren Naish
Yes, it&rsquo;s an entelodont &ndash; a member of a group of fossil artiodactyls  that inhabited North America, Eurasia and Africa between the Eocene and  Miocene, with the oldest species in the group being those of Middle  Eocene Asia.
Entelodonts (properly Entelodontidae) have generally been regarded as  suiforms (close kin to pigs and peccaries) but some recent analyses have  found the sampled members of the group to be members of the hippo +  cetacean clade Cetancodontamorpha (O&rsquo;Leary &amp;amp; Gatesy 2008, Spaulding et al. 2009) and hence fairly well removed phylogenetically from pigs and peccaries. Andrewsarchus,  the famous Eocene giant predator or omnivore so often regarded as a  mesonychian (or mesonychid), seems to be a cetancodontamorphan close to  entelodonts (see the links below for much more on Andrewsarchus).
Entelodonts are widely regarded as omnivores that scavenged dead animals  and, at least sometimes, caught and ate live ones. Evidence for this  omnivorous lifestyle comes from their pointed incisors, recurved,  pointed, serrated canines , serrated premolars and an unusually mobile jaw joint. Further evidence comes from studies on bite strength  (Effinger 1998, Joeckel 1990) and from bite marks left on the bones of  other mammals (Hunt 2005). Oh yeah, and there&rsquo;s the discovery of a pile  of bitten-in-half little camels from the Early Oligocene, the marks on  their bones matching the tooth anatomy of the entelodont Archaeotherium (Sundell 1999).  Massive bony cheek flanges and bony tubercles on the lower jaw might  have been used in intraspecific fights, and some specimens preserve  skull injuries apparently inflicted by other entelodonts&amp;#8230;
(read more: Tetrapod Zoology blog at Scientific American)
(image: Entelodon by Jaime Chirinos)