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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.
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
Wooly Rhinoceros by Charles Knight (Los Angeles Natural History Museum)
Sadly, today the rhinoceroses are few on the ground. There are only five extant species of the family Rhinocerotidae and none of them are doing well–because of habitat loss and humankind’s obdurate (and extraordinarily foolish) belief that rhino horns have magical supernatural powers. Yet once the rhinos were a mighty force—in fact, the largest land mammal ever, the Paraceratherium, was a sort of rhino. There used to be multiple tribes of Rhinocerotidae, each containing numerous genera (which could in turn contain dozens of species) of these great horned perissodactyls. None of the extinct rhinos was more splendid that the magnificent wooly rhino (Coelodonta antiquitatis) which roamed Eurasia during the icy Pleistocene epoch and even survived (probably) up until the beginnings of human civilization.
The comparative size of a Wooly Rhinoceros
A wooly rhinoceros was a substantial creature. From fossils and mummified remains, we know they measured around 3 to 3.8 metres (10 to 12.5 feet) in length, and had an estimated weight of around 2,700–3,200 kg (5,999–7,000 lb)—so they were not much smaller than the still-living white rhinoceros (although wooly rhinoceroses are more closely related to the contemporary Sumatran rhinos—which do not become so big and heavy). As you might guess from the name, wooly rhinoceroses had magnificent hairy coats to help them survive the cold and they had two large horns for defense and for mating displays. For a long time, paleontologists have argued about whether the Coelodontas grazed grasses or browsed on tender shoots, berries, and mosses, but paleobotanical evidence (taken in tandem with fossilized skeletal features) now seems to indicate they were browsers, like bison or cows.
Wooly Rhinoceros (Illustration by Charles R. Knight, National Geographic)
Wooly rhinos roamed the frozen steppes of Eurasia–a habitat which was much larger in those days due to the ice age and the lower sea levels of the Pleistocene. For example, wooly rhinos could be found on the dry & icy wastelands of Southern England and they thundered across the cold plains which would later become the fertile hunting lands of Doggerland (which are now submerged beneath the North Sea). They were also prevalent across northern Europe and down through Central Asia all the way to the Tibetan Plateau.
Wooly Rhinoceros from Chauvet Cave (ca. 30,000-32,000 years ago)
Based on cave paintings from tens of thousands of years ago, humankind seems to have had an early fascination with these great furry beasts. Unfortunately the last wooly rhinos apparently went extinct around eight to ten thousand years ago (according to somewhat disputed carbon 14 readings from a specimen found frozen in the Siberian permafrost). Many large species of Paleocene megafauna died off at approximately the same time: whether the great behemoths went extinct from humanity’s increasingly effective hunting, climate change, or from some great pandemic which affected large animals is unclear (although contemporary scientists have been inclining towards climate change as a primary cause).
Woolly Rhinoceros Hunt (diorama from Horniman Museum, London)
The Elk (Cervus Canadensis)
The Elk (Cervus Canadensis) is one of the world’s largest deer: adult male elk can weigh up to 331 kg (730 lb) and stands 1.5 m (4.9 ft) at the shoulder. The magnificent antlered beasts are believed to have originated in Beringia, a now vanished steppeland which connected North America and Asia during the Pleistocene. The poor Elk suffers substantial name confusion. In Europe, moose (Alces alces) are known as elk. When Europeans arrived in North America, they thought the animals were similar so they christened Cervus Canadensis as “elk”. Native Americans called the creatures wapiti. Now elk are known by the European name “Elk” in America and the American name “wapiti” in Eurasia (so that they are not confused with moose which are still called elk). Ugh!
The current range of elki/wapiti (dark green) versus the original range (pale green)
Elk currently live in the great grasslands of northern China/Siberia and in the unpopulated western reaches of the United States and Canada (where they tend to be found in places like Wyoming and Colorado), however their range was once much more extensive. Before development and farming became universal, elk could be found in South China and in the Eastern United States. Kentucky has been experimenting with returning the great Elk herds to lands where they once last roamed wild before the Civil War. Obviously nobody wants to abandon farmlands or private forests to the ungentle hooves of a giant deer-monster, but Kentucky was extensively and abusively strip mined. The mountains were blasted down and great tracts of worthless wasteland was left. Far-sighted conservationists imported elk from out west, and the animals flourished tremendously. In less than two decades the Kentucky herds have become the largest in the nation outside of the world’s largest herd in Wyoming!
The elk have brought tourism and national interest to their new (old?) home but there have been problems too as elk refuse to jump out of the way of cars and angry drivers, refusing to yield the right-of-way, drive blithely into the immense creatures (to the benefit of neither party). The elk also damage cultivated trees and gardens. Yet issuing hunting permits in order to manage the herd has brought waves of hunters.
A votress of Artemis poses with a trophy elk. Have I mentioned how BIG elk are?
Additionally, the elk are beautiful–and were here before we were (well, probably… it’s a little hard to tell when humans came across Beringia, but we had to get there from Africa, whereas the elk started out there). Nearby states are also excited by the programs so Virginia, Ohio, and West Virginia may soon also have beautiful deer monsters of their own for the first time in centuries!
A Smilodon fends off the vulture-like Teratornis at what would later be called the Rancho La Brea tar pits, situated in Los Angeles, California (Painting by Charles R. Knight)
Lately this blog has been fixated on magnificent saber-toothed mammals. We have featured the extinct saber-toothed whale, a saber-toothed marsupial predator, the little saber-toothed deer, and even the familiar walrus (in reality, a giant saber-toothed seal), but we realize that everyone has really been looking forward to the most famous saber-toothed animal of them all, Smilodon, the saber toothed cat. Smilodon was actually a genus of several large cats, the biggest of which, Smilodon populator, weighed 360 to 470 kg (790 to 1,000 lb) and was larger than modern tigers or lions. In fact Smilodon species are sometimes known as “saber toothed tigers” or “saber toothed lions,” however taxonomists tell us such names are off the mark since the Smilodons belonged to the extinct Machairodontinae genus of felines rather than the familiar Panthera genus of big cats so familiar today.
About two and a half million years ago, Smilodon evolved in North America from an earlier genus of saber toothed cat Megantereon (there were a lot of other earlier genera of saber-toothed cats, not to mention even more genera of saber toothed carnivores which were not exactly felines—the whole story is complicated). During the Great American Interchange with South America the big predators invaded South America at the same time armadillos were making their way up into North America. Yikes, that’s a pretty lopsided exchange.
In addition to long razor sharp teeth, Smilodons possessed immense neck and forelimb muscles. Using the muscles of their front torso they would pull down and pin the great grazing metafauna of the American plains. Prey animals almost certainly included bison, tapirs, deer, American camels, and ground sloths. Additionally Smilodons might have opportunistically killed juvenile mastodons and mammoths. To dispatch such large prey Smilodons employed their fearsome canine teeth with which they bit through the prone creatures’ necks.
Smilodon fatalis (reconstruction/specimen at the Page Museum)
Paleontologists have collected a great deal of fossil evidence concerning Smilodons, which suggest that the big cats were sophisticates social predators like today’s lions or wolves. The number and nature of saber-toothed cat fossils recovered from tar pits suggests that Smilodon prides would converge together on prey animals caught in the petrochemical ooze–only to become trapped themselves. Also some fossilized smilodons have shown evidence of badly broken bones healing—a rarity in carnivores which is generally only possible for pack/pride animals which can (sometimes) rely on a support network.
Thanks to their size, ferocious appearance, and highly characteristic teeth, Smilodons have a special place in human culture to the extent that few other extinct animals do. The Flintstones had a pet smilodon named “Baby Puss” which evicted Fred from his house in the title sequence and the moral struggles of Diego the saber tooth constituted the moral hook of “Ice Age” a cartoon movie. Ironically for all of our apparent fondness for the great cats, it seems that human migration into the Americas may have been the downfall of the great cats (which vanished 10,000 years ago) but whether their extinction was the result of humans overhunting their prey, shifting climate, or some other factor remains an open question.
Smilodon by Knight
Irish Elk (Painting by Charles R. Knight)
Megaloceros giganteus was the largest deer to ever exist. The huge animal would have stood 2.1 meters (over seven feet) tall at the shoulders and had antlers more than 3.65 meters (12 feet across). During the Late Pleistocene (the glacial epoch immediately prior to the Holocene) the giant deer ranged from Lake Baikal in northern Asia across all parts of Europe down into northern Africa.
In English, Megaloceros giganteus, is more commonly known as the Irish Elk, a name which is something of a misnomer since the creature lived across broad swaths of three continents and was not actually very closely related to elk and moose. The name was originally adopted because many nearly perfect fossils of the Megaloceros were found in the great peat bogs in Ireland. So perfect were the skeletons that a misguided biological theorist, Thomas Molyneux, used the remains as evidence that no species ever went extinct (a question which was at the forefront of science at the end of the eighteenth centery). Molyneux believed that the Irish Elk skeletons were actually those of large moose or elk and that divine providence would never allow an animal to disappear forever from earth. Unfortunately Molyneux was completely mistaken. The great zoologist, Georges Cuvier comprehensively proved that the Megaloceros was very distinct from living Moose and Elk and was therefore gone from the world. It is strange to think that there was a time as recent as the nineteenth century when natural philosophers argued about whether extinction was possible or not.
A painting of Megaloceros giganteus, from the Lascuax caves (at least 10,000 years old).
Although the Irish Elk coexisted with humankind for a long time, sadly something went awry and the great beast went extinct at least 7,700 years ago. Strangely, overhunting by humans was probably not the reason the Megaloceros died out. However the actual reason for the extinction of the magnificent mammal has been a long standing cause of dissent among paleontologists. An obsolete school of thought held that the creatures’ antlers became so immense that the beasts could no longer hold their heads up. A likeminded school of thought believed the antlers (which grew larger and larger in response to female’s preference for a mate with big antlers) left the animal unable to compete with smaller and more nimble competitors. A new theory concentrates on the amount of calcium and phosphate necessary to grow such stately and humungous antlers. As vegetation changed in response to the end of the ice age, the poor Irish Elks could not get enough of the proper nutrients and began to suffer like old ladies from osteoporosis. A final answer to the mystery is still outstanding.
Irish elk (Megaloceros giganteus) RIP
Turkeys have been widespread and successful since the early Miocene (23 million years ago). Since their robust bones fossilize quite well, a number of extinct turkeys are known to paleo-ornithologists (including two genera which do not exist today, the “Rhegminornis” and “Proagriocharis”).
The best known of these vanished turkeys is the Californian Turkey, Meleagris californica, which died out about ten to twelve thousand years ago as the ice ages ended and human settlements became common. The Californian turkey had a shorter beak and a stockier build than contemporary turkeys but it was a similar creature and probably shared many of the habits and vocalizations familiar to us. Its remains have been discovered profusely in the tar pits of southern California, where it must have been preyed on by the great carnivores of that Pleistocene. Californian turkey bones have also been found in camp middens of ice age humans, whose love of succulent turkey dinners may have combined with climate change to usher the poor birds to extinction.
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