You are currently browsing the tag archive for the ‘scavenger’ tag.

Giant Short-Faced Bear (by Joseph S. Venus)

Giant Short-Faced Bear (by Joseph S. Venus)

With the possible exception of the polar bear, the brown bear is the largest land predator on Earth today—which brings up the question of whether there were larger bears alive in prehistory. Amazingly, the answer is a resounding yes!  The short-faced bear (Arctodus simus) lived in North America during the Pleistocene.  It ranged from Alaska down to the Gulf of Mexico.  The huge bears first appeared 800,000 in the past: yet they only died out 12,500 years ago (a time which coincides suspiciously with the proliferation of humans in the Americas).  The largest short-faced bears are estimated to have weighed up to 957 kilograms (2,110 pounds) and they stood 1.5 meters (5 feet) tall at the shoulder.02bear2

The short-faced bear derived its name from its broad squat muzzle—a feature which gave the bear an incredibly powerful bite.  Using these powerful jaws the bears could crack open huge bones and gobble up the marrow.  Yet short faced bears also had longer thinner legs and arms than living bears.  The combination of graceful runners’ limbs and bulldog-like muzzle has greatly perplexed scientists.  Was the bear a predator who ran down Pleistocene megafauna and then bit its prey to death, or was it a huge scavenger which wondered across the continent looking for carrion to crack apart with its ferocious jaws.  There is still not scientific consensus about the lifestyle of the immense bear, however what is certain is that the short-faced bear was one of the two largest mammalian land predators known to paleontology (the other contender for the title is the even-more-mysterious Andrewsarchus).

The fossilized skeleton of a short-faced bear at the (amazing-sounding) American Bear Center

The fossilized skeleton of a short-faced bear at the (amazing-sounding) American Bear Center

Andrewsarchus Skull at the American Museum of Natural History

In the summer of 1923, Kan Chuen Pao unearthed an enormous skull from the baking Gobi desert of Mongolia.  Pao was a member of a paleontology expedition led by Roy Chapman Andrews, a world famous explorer, adventurer, and naturalist who, during the course of his career, rose from being a janitor at the American Museum of Natural History to being its director.  The skull they found was an enigma—the creature was a mammal with immensely powerful jaws but blunt peg-like teeth. No substantial bones were found other than the skull sans jaw (nor have any further specimens ever been discovered). The skull was discovered in sediments deposited during the late Eocene, the sweltering summer epoch when most extant mammalian orders evolved, so it is probably 36 to 40 odd million years old.  Andrews was immediately of the opinion that it was a huge carnivore, but what sort of creature was it really?

A toothy hairy model of Andrewsarchus

The creature was named Andrewsarchus mongoliensis in honor of Adrews and his expedition.  Andrewsarchus may have been the largest mammalian carnivore ever (although short faced bears might have been larger).  The one skull, currently in New York, measures 83 cm (33 inches) long and 56 cm (22 inches)wide–which suggests the animal may have been 3.4 meters (11 feet) long and nearly 2 meters (6 feet) tall at the shoulders.  Such a creature could weigh more than 1000 kg (2200 lb).

A drawing of Andrewsarchus with a large ninja to explain scale (Picture Credit: Everything Dinosaur)

But Adrewsarchus may not have been a carnivore:  ever since the beginning of the jazz age, Paleontologists have argued about the monster’s diet.  Andrewsarchus lived along the coast of the eastern Tethys Ocean, a sea which was dried out and destroyed when the Indian subcontinent barreled into Asia during the late Eocene/Early Oligocene.

A Delightful Andrewsarchus model/toy produced by Bullyland

Some scientists believe the creature was a hunter which captured the giant land animals of the time. Other scientists believe the animal was a scavenger which lived on the rotting carcasses of primitive whales and beached sea turtles.  Another group feels that the creature fed on huge beds of shellfish, and a final school holds that the animal was even larger than believed and was at least part-herbivore!

An unpainted model of an athletic hunting Andrewsarchus (as envisioned by Paleocraft)

The taxonomy of Andrewsarchus is equally confusing.  The great skull was initially classified as a giant creodont (an extinct order of alpha-predators which share an ancestor with today’s carnivore).  The first scientific paper about the creature by great paleontologist and…um, eugenicist, Henry Fairfield Osborn, states, “An outline sketch of the skull was sent in a letter to the Museum, from which Dr. W. D. Matthew immediately observed its real affinity to the primitive Creodonta of the family Mesonychidae.”

Later scientists have been less certain about lots of things than Osborn was and Andrewsarchus’ place in the mammalian family is now unclear.  A consensus is emerging that the great creature shared common ancestors with the artiodactyls (like hippos, deer, and pigs).  Perhaps its heritage provides insights into the link between the artiodactyls and their close (yet oh so distant) cousins the whales.

A digital Andrewsarchus pensively gnawing a bone beside the Eastern Tethys (from BBC’s “Walking with Beasts”)

Whatever the case is, these giant hoofed creatures with their immense powerful maws must have been amazing and terrifying to behold.  Their fate seems to have been sealed as the Tethys closed and the Gobi basin dried out, but, whenever I think of the harrowing deserts of Mongolia and China, I imagine their fearsome toothy spirits towering over the other strange ghosts of that haunted place.

Ye Olde Ferrebeekeeper Archives

July 2020
M T W T F S S
 12345
6789101112
13141516171819
20212223242526
2728293031