Monday, December 31, 2012

Giant Bears Terrorized Ancient America

by Dr. E.J. Neiburger

Man has occupied the Americas for the last 50,000 or 60,000 years. His earliest habitation sites cluster in South America. But why didn't early humans settle in North America before colonizing distant areas farther south? Perhaps the answer may become self-evident in the following conjectured scenario from the distant past.

Boki finally completed the long walk over the cold and windy land- and ice-bridge later known as the Bering Strait. He and his paleo-Asian band moved south along the great water to a land beyond the glaciers. The land had dense pine forests and much game. A shadow also traveled with them. It was cast by a giant bear.

Boki and his band called the roaring creature "Gor." He was a terrible spirit, not like the more common brown or black bears. Gor was much, much larger than a big, shaggy Kodiak or ghostwhite polar bear. He stood two or three times the height of the tallest man. His arms could spread the distance of two men placed head to toe. His claws were longer than a man's hand. Gor could not be killed. Many parties of warriors went out to battle him with traps, pit falls, and spears. None returned. He was a spirit with hide so thick it could stop the sharpest obsidian spear. They were unable to trap him, because his giant claws could lift his massive body out of any dead-fall pit or cave.

The paws were powerful enough to snap a tree as thick as a man's leg. No woven rope could hold him. Gor was always hungry and always near by. He followed the band of hunters wherever they camped. If they hid, he caught their scent and dug them out of their holes. He ran them down in the meadows, where he would swat the puny humans to the ground and crush their heads with a single bite. And he was clever. He often laid quietly until darkness fell, then swiftly lumbered into camp and took a human or two for dinner. Some hunters might stop to throw spears or torches at Gor. Others tried to outrun him, but always failed. Their band was growing smaller. But the monstrous bear was relentless.

Although the foregoing recreation was fictitious, Gor was not. Arctodus simus, the giant, short-faced bear of North America, did indeed exist. He roamed the upper reaches of the North American continent from approximately 36,000 Years Before Present to only about 5,000 years ago, at the end of the Pleistocene Age. Arctodus was a contemporary of Ice Age man, the mammoth and other giant mammals. Some scientists believe his presence was an irresistible pressure for early North American man to quickly move south and populate the warmer areas outside the monster bear's range in Central and South America. Arctodus was a giant. His fossilized bones belonged to a beast that towered 12 to 14 feet high when standing upright, 5 or 6 feet high at the shoulder when down on all fours.

Other fossils show he was 80 percent to 120 percent larger than the biggest modern Kodiak bear. Average polar or grizzly bears weigh about 500 pounds. The largest modern male polar bear is recorded at about 900 pounds. The largest Kodiak reached 1,150 pounds. Arctodus was much heavier. He was similar to a grizzly, save for his longer front legs and a pushed-in, shortened, broader muzzle. The Indiana fossil of a medium-sized Arctodus revealed a 9 foot front arm span, and an estimated weight of 2,575 pounds (776 kilograms). Fossils of this bear are a third larger than the Indiana fossil.

Extrapolating these findings, some fossil Arctodus individuals could have reached 3,500 pounds during their lifetimes, triple the size of the largest modern Kodiak bear. If we assume that the population- size range of Arctodus was similar to that of modern bears (some individuals are twice the size of the average bear), then there probably were at least some 5,000 pound bears (twice the size of the Indiana fossil) that stood more than 20 feet tall. Fossils of Arctodus have been found in more than 100 locations, including the Yukon, Kentucky, Pennsylvania, Indiana, California, and northern Mexico. These types of slash-marks could have been made with a Clovis paleo-Indian spear point. It may be that the Arctodus-human interchange was not always a one way relationship.

As are modern bears, Arctodus was an omnivore; in other words, he ate everything-plants, as well as animals. Studies of his fossil remains show that he suffered many of the illnesses occurring in mammals today, including man. Because of his size and habitat, painful arthritis and fungal infections were common and, in all probability, kept Arctodus in a continuously irritated, mean mood. The enormous size and frequency of remains are the impressive aspects of this beast. Its wide distribution and physical power probably influenced the rapid human migration to Central and South America. Fossils of large animals are rare, and the recovery of 100 of them indicates a very large population, because only a minute percentage (one in a million) of any group of animals will become fossilized.

There were many Arctodus bears, and as the populations of mammoth, mastodon, giant beaver, musk ox, and sloths disappeared, man became a prime food source. How could such an animal, even if it was big, force large numbers of well-organized (tribal) humans, armed with spears, traps, and knowledge of killing large game such as mammoths, to literally run to safer areas in South America? The answer is quite simple. The bears were tougher than humans. Today, we have little experience in hunting bear with the weapons available to early Asian immigrant hunters.

It is a considerable jump from shooting a 600-pound Kodiak with a high powered, long range, semi-automatic rifle, as compared to running up to the enraged creature and poking a spear or arrow into his tough, thick hide. Even if one were about to penetrate the skin, a 5-inch-thick layer of fat covered the muscle. Five to 8 inches of muscle protected the vulnerable internal organs, so penetration power of a foot or so was necessary to inflict Arctodus with a fatal wound. Such weapon penetration technology was not usually available to the paleo-hunter; even if he chose to commit suicide with a close-contact assault.

The power of bears was well documented by Lewis and Clark in their report to President Jefferson (1807) concerning experiences with relatively small, but newly discovered grizzlies on their expedition to the Pacific coast. Lewis states, "The men, as well as ourselves, were anxious to meet with some of these bears. The Indians give a very formidable account of the strength and ferocity of this animal, which they never dare to attack but in parties of six, eight, or ten persons; and are even then frequently defeated with the loss of one or more of their group members."

On 5 May 1805, Captain Lewis reported a "monster" bear (later weighed at 600 pounds), which required ten shots-five of them through the lungs-to kill it." Even though severely wounded with nine shots from the .69 caliber Harpers-Ferry rifles, the grizzly chased the hunters down a 20-foot perpendicular embankment and into the river. The bear was finally killed with a 10th shot to the head. Such ferocity and danger involving relatively "tiny" bears as experienced in Lewis's report must be multiplied several times over for creatures as big as Arctodus.

Another problem encountered by early man was bear intelligence. The relative brain/body-size ratio of Arctodus was comparable to that of modern bears. This implies that Arctodus probably had the same intelligence of modern bears, who are really quite smart. Some recent news stories coming out of our U. S. national parks illustrate this point. Park bears are generally pests constantly looking for food. Hanging food from campground poles or trees became ineffective when the bears discovered how to chew the ropes and drop the food bags. Metal lockers were installed but the bears learned how to open the locks. Numerous cars were systematically vandalized by some bears who broke windows, tore off the doors, and got into the trunk area by removing the back seats. The record of this activity was a mother bear and her two cubs who "processed" 44 cars in one weekend.

Our Ancient American ancestors faced Arctodus-numerous, giant, ferocious, unstoppable, and intelligent bears. No wonder they quickly moved to Central and South America. They wanted to be out of range from the largest carnivore since the days of the dinosaurs!

For some unknown reason, about 5,000 years ago, Arctodus became extinct. Perhaps the scaled-down versions of flat-faced Arctodus (grizzly brown bears) or pointed-faced black bears were more efficient food gatherers in a post glacial, changing environment. It is also possible that new diseases finished off the big bears. We really do not know, but in the evolutionary-natural selection scheme, smaller-sized game often results in smaller-sized carnivores. Around 5,000 Years Before Present, North American game such as mammoth, musk, and ox, were relatively small. But before then, giant bears roamed North America, and human beings were their prey.

No comments: