The fate of the cave bear

HervéBocherens said that his colleagues found his research method a bit "rough". He dissolved 30,000-year-old animal bones in hydrochloric acid, which was strong enough to burn through metal, soaked the bone solution in alkaline solution, cooked it at about 200 degrees Fahrenheit, and then freeze-dried it until the rest was a little powder weighing less than 1% ounces. This method may be harsh, but the yield is a precious chemical biography of the cave bear.

Bocherens, an evolutionary biologist at the University of Tubingen in Germany, is a pioneer in studying bears, which became extinct in Europe 25,000 years ago. In the Middle Ages, people have been digging for the remains of cave bears for hundreds of years. Huge skulls are thought to be the remains of dragons, but in the past ten years, people have found a lot of information about how bears lived and why they became extinct. From Spain to Romania, a large number of bear bones have been found in caves where these animals used to hibernate. "Caves are good places to preserve bones, and cave bears have a good sense of death there," Bocherens said.

Mammoths, lions, hairy rhinos, and Usspe Lahousse were once one of the most impressive creatures in Europe. Males weigh 1500 pounds, which is 50% heavier than the largest modern grizzly bear. Cave bears have wider heads, strong shoulders and forelimbs than modern bears.

Prehistoric humans painted animal images on cave walls and carved their portraits on ivory fragments of mammoths. But the relationship between humans and cave bears has always been mysterious. Are humans prey or predators of bears? Is the bear the object of worship or fear? "

Cave bears have evolved in Europe for more than 654.38 million years. At first, they shared this continent with Neanderthals. Archaeologists once thought that Neanderthals worshipped bears and even shared caves with them. This idea was popularized in Jean Hall's 1980 novel The Cave Bear Family, but was later rejected by researchers.

Modern people came to Europe about 40 thousand years ago and soon realized the bear. There are lions, hyenas and bears painted on the walls of the cave in Jowett, which was occupied 32,000 years ago. This is probably the oldest painting in the world.

The artist is not the only resident in the cave: the ground is covered with the bones of 150 cave bear, and its soft clay still retains the fingerprints of claws and the obvious dents of the bear. The most striking thing is that the skull of a cave bear was placed on the slate in the center of a cave, which was deliberately placed by some cave residents who had already disappeared, and their thumbs were pointed. Bocherens said, "We can't judge whether curiosity makes people put skulls on rocks or whether it has religious significance. Another discovery, hundreds of miles east of Chavez, will reveal the relationship between cave bears and humans.

Svabieula is a limestone plateau in southwest Germany, full of caves. A short walk from the village of Shel Klingen, visitors can reach the foot of the limestone cliff in Archie Valley. A steel door guards the Huo Lefel Cave to prevent vandalism and curious people from entering. Inside, the sound of dripping water competes with the quiet conversation of six archaeologists and the main caves in the cave.

The floodlights lit up the ceiling, and the vault was like a cathedral over 5,000 square feet. Long ago, the bones and tools discovered by archaeologists showed that cave bears and humans came here to escape the winter weather.

In 2000, Suzanne Münzel, a paleontologist at the University of Tubingen, discovered a bear spine embedded with a small triangular flint. This stone is probably a broken spear tip, which is a strong evidence of successful bear hunting 29,000 years ago.

Münzel also found bear bones that were obviously scratched by stone tools. Incisions on the skull and leg bones indicate that the bears have been skinned, and their meat shh, go away. "She said," someone must be hunting cave bears, or you can't find the meat with the bones cut off. . Many bones come from cubs and may have been caught during hibernation.

After humans spread all over Europe, cave bears soon disappeared. Will hunting lead to bear extinction? ? Eric Trinkaus, an anthropologist at Washington University in St Louis, thinks this is unlikely. "People who lived in the late Pleistocene were not stupid," he said. They spend a lot of time to avoid being eaten, and one way is to stay away from big bears. "If hunting is an isolated event as he said, it must be another reason for the extinction of bears.

HervéBocherens's test tube may have a clue. He analyzed the white powder by mass spectrometer, and determined elements with different isotopes or chemical forms, such as carbon and nitrogen, which reflected what bears ate and their growth rate. After studying hundreds of bones in dozens of places in Europe, Bocherens found that cave bears mainly eat plants.

This will make bears particularly vulnerable to the last ice age, which started 30,000 years ago. The long cold period shortened or eliminated the growing season and changed the distribution of plant species in Europe. According to the DNA analysis of teeth found near the Danube by researchers at Max Planck Institute in Leipzig, cave bears began to migrate from their original territory. The cave bear population there has been relatively stable for about 654.38 million+years, and the same genetic pattern has appeared from generation to generation. But about 28 thousand years ago, newcomers came here with different DNA patterns-which may be a sign that hungry bears suddenly acted.

But climate change can't be just the culprit of bear extinction. According to Max Planck Institute (Max? According to the latest DNA research of Planck Institute, including Bocherens, Münzel and Trinkaus, the number of cave bears began to decline long and slowly 50,000 years ago, much earlier than the beginning of the last ice age.

This new study does support another explanation for the death of the cave bear. With Neanderthals and more and more modern people moving into caves in Europe, there are fewer and fewer safe places for cave bears to hibernate. The severe housing shortage may be the final blow of these behemoths.

Andrew Currie often writes articles on archaeology and history for the Smithsonian Institution.

Susanna Mansel found the cave bear bones with scratches and gouges. (University of Tubingen) A bear bone with scratches and gouges. (University of Tubingen) Do bears eat people? Herve Pochelens of Ventoux Cave says they mainly eat plants. (University of Tubingen) Kroma farmers can vaguely see cave bears in their minds, as shown in this picture of Jowett Cave. (Jean Crotes)