Posts Tagged ‘The American hyena’

The American Hyena (Chasmaporthetes ossifragus)

October 1, 2013

In 1921 Oliver Hays was the curator of a museum that eventually became the Smithsonian.  One day, he was examining fossils that had been collected from the Val Verde Copper Mine in Anita, Arizona 20 years earlier.  Barnum Brown, a world renowned fossil collector at a time when fossil hunters were celebrities, had labeled 1 specimen as “cat.”  This curious specimen consisted of just a lower jaw. After much pain-staking comparisons with other specimens, Oliver Hay concluded the jaw belonged to an extinct species of hyena that he named Chasmaporthetes ossifragus.  The paleontological community doubted Hay had correctly identified the specimen.  It was nearly 50 years before enough evidence had accumulated to verify Hay’s conclusion that hyenas once roamed North America.

Artist’s depiction of Chasmaporthetes–the hunting hyena.  It was a fast runner and an important carnivore on 4 continents during the Pliocene.

Chasmaporthetes ossifragus, known as the hunting hyena, lived in North America from about 4.9 million years BP to ~780,000 BP, making it an important large carnivore of the Pliocene and early Pleistocene.    It had long strong legs and is thought to have been an active hunting animal that chased its prey down, possibly in packs.  Although it possessed a powerful bite and did eat some bone, it didn’t eat as much bone as the modern extant spotted hyena (Crocuta crocuta).  It lived alongside other large predators such as the bone eating dog (Borophagus diversidens), the giant cheetah (Acinonyx), the scimitar-toothed cat (Dinobastis), and the dirk-toothed cat (Megantereon).  It likely preyed upon horses, llamas, camels, peccaries, deer, pronghorn, marmots, and other small mammals.

Fossil remains of Chamaporthetes have been found at 4 sites in Florida, 3 sites in Arizona, 2 sites in north Texas, 2 sites in Mexico, and 1 site in New Mexico.  It is the only species of hyena known to have crossed the Bering landbridge to North America where it was likely more widespread than its fossil record would indicate–there just aren’t many Pliocene-aged fossil sites in the midwest and northeast.  A similar species, Chasmaporthetes lunensis, lived in Europe, Asia, and Africa during the same time period, and it may actually be the same species.  This means the hunting hyena was 1 of the most wide ranging and successful large carnivores ever.  The reason for its extinction is unknown, but it disappeared at a time when forests were replacing grassland and desert habitats.  Archaic species of wolves ecologically replaced American hyenas, but it’s not known whether they outcompeted them or simply took advantage of an extinction that occurred due to other causes.

Despite their appearance, hyenas are more closely related to cats than dogs.  The order Carnivora is split into 2 suborders–feliforms and caniforms.  Feliforms include cats, civets, mongoose, and hyenas while caniforms include dogs, bears, weasels, skunks, pandas, raccoons, and seals.  There are 4 extant species of hyena.  The odd little aardwolf (Proteles cristata) is a nocturnal solitary animal that primarily feeds upon termites.  The brown hyena (Hyeaena brunnei) is a solitary scavenger that lives in South Africa.  The striped hyena (Hyeaena hyeaena)  is also a solitary scavenger, but it lives in North Africa, the Middle East, and India.  The spotted hyena ranges all across Africa and is more of an active pack hunter than the striped and brown hyenas.  It’s the species most commonly filmed for nature documentaries.  During the Pleistocene, spotted hyenas lived across Europe and Asia, and they occasionally fed upon humans.  Once in a while, archaeologists find hyena dung in caves that contains human hair and bones.

Most Homo erectus bones found in Asian caves were dragged inside by hyenas.

Oldest human hair known.  It was found in hyena dung, dating to between 250,000 BP- 195,000 BP.