Creature of the Week #27: Andrewsarchus

In the TV series Walking With (Prehistoric) Beasts Andrewsarchus is depicted as a mighty mammalian monster - the largest meat eating mammal of all time, eating virtually anything unlucky enough to cross it's path.
Seen here in a music video mash up:


But what do we really know about Andrewsarchus? Surprisingly little in all actuality. The name Andrewsarchus mongoliensis means "Andrews'(as in legendary fossil hunter Roy Chapman Andrews) ruler of Mongolia". The only remains of this animal is a single incomplete 32" x 22" skull (upper jaw only) and a few scraps of bone found in Mongolia and dating from around 40 million years ago during the Eocene. You can see a cast of the skull for yourself in the American Museum of Natural history in New York.


Or just look at this picture.

A strange looking beast, Andrewsarchus has been fancifully described as a sheep in a wolf's clothing as it's closest living relatives are believed to be goats while it appears to be a carnivore. However, said relationship with sheep may be incorrect. Some speculate that Andrewsarchus is related more closely to pigs while others suggest that it is so unique that it belongs in a group of it's own.
So what the heck is it? The short answer is we simply cannot be sure until more remains are found. What we do know is that it was really big. Estimates vary, but the most liberal place it as being some 13 feet in length, over 6 feet tall and weighing in around a metric tonne (1,000 kilograms/2,200 pounds).

Those measurements may not sound all that impressive compared to say the larger meat eating dinosaurs who could weigh in excess of 6 tonnes and stretch to over 40 feet in length, but I assure you if you met one in the flesh you would probably be a lot more concerned than the girl in the illustration above. Keep in mind Andrewsarchus was twice the size of the largest mammalian carnivore of today, the polar bear - an animal capable of hunting whales. Perhaps ironically, seemingly the only mammalian predator bigger than Andrewsarchus was another type of bear, Arctotherium of Pliocene South America.

So what did Andrewsarchus eat? It's blunt teeth are not immediately recognizable as those of a predator, leading many to believe it to be an omnivore, eating a combination of plant matter and meat. However, it's jaws would have been immensely powerful, capable of crunching through even very large bones. Some argue this as evidence of Andresarchus' nature as a scavenger while others believe the crushing bite negated the need for sharp teeth, allowing Andrewsarchus to deliver a powerful killing blow to it's prey using sheer brute force. Curiously, Andrewsarchus fossils are found in coastal deposits so it may have combed beaches looking for easy prey such as turtles, beached whales or unsuspecting small crocodiles.
No one can be completely certain as to exactly what this curious animal was using it's jaws to eat. The best we have to work on for now is speculation.

And speculation is an awful lot of fun!

Speaking of fun, here is Andrewsarchus standing next to several really big things...