Study: Early Humans Partly to Blame for Cave Bears’ Disappearance

 

New research suggests that human beings may have been partly responsible for the disappearance¹ of cave bears thousands of years ago.

The plant-loving animals once lived across Europe. Some experts had believed that the cooling climate during Earth’s Ice Age was to blame for their extinction².

Scientists reported last week they had studied genetic³ data from 59 cave bears. Their bones were recovered from six countries: France, Germany, Italy, Poland, Serbia, Spain and Switzerland.

From the genetic information, the scientists noted⁴ a decrease in the cave bear population beginning about 50,000 years ago. That is around the time of the arrival of Homo sapiens, or modern humans, in Eastern Europe. The researchers said they observed a sharp drop in the bears’ numbers about 40,000 years ago. That coincides with the spread of Homo sapiens throughout Europe.

The animals went extinct about 20,000 years ago.

The cave bear lived in Ice Age Europe at the same time as other now extinct creatures, such as the cave lion, woolly mammoth⁵ and woolly rhinoceros⁶. The bear was as big as a modern polar bear, but ate only plants. It appears often in prehistoric⁷ cave paintings.

There has been a scientific debate about what led to the extinction of the cave bear. Some scientists believe that the cooling climate greatly reduced the availability of the plants they needed for food. Others have blamed human activity, including hunting and taking over the caves where the bears gave birth and slept during winter.

The population decrease identified in the study began before the climate cooling connected with the most recent Ice Age, says Verena Schuenemann. She is a paleogeneticist at the University of Zurich in Switzerland.

The bear’s population remained largely unchanged for long periods before that, including during two noticeably cold periods and other cooling events, she added.

Homo sapiens appeared in Africa more than 300,000 years ago and later moved to other areas. The study offered new evidence that the arrival of Homo sapiens lead to ruin for many kinds of animals across Eurasia, the Americas and Australia.

Hervé Bocherens is with the University of Tübingen in Germany. He said, “There is more and more evidence that modern humans have played a determinant role in the decline and extinction of large mammals once they spread around the planet.”

Bocherens noted that Homo sapiens started moving out of Africa about 50,000 years ago. Before their arrival in Europe, the bear’s population had remained strong, even while it shared its territory with another human species, the Neanderthals.

Neanderthals also went extinct after Homo sapiens arrived in Eurasia.

A report on the study appears in the publication Scientific Reports.

I’m Ashley Thompson.

Words in This Story

extinction - n. the state or situation that results when something (such as a plant or animal species) has died out completely

data - n. facts or information used usually to calculate, analyze⁸, or plan something

coincide - v. to happen at the same time as something else

determinant - n. a thing that controls or influences what happens

decline - n. a change to a lower number or amount

1 disappearance   

n.消失，消散，失踪

参考例句：

• He was hard put to it to explain her disappearance.他难以说明她为什么不见了。
• Her disappearance gave rise to the wildest rumours.她失踪一事引起了各种流言蜚语。

2 extinction   

n.熄灭，消亡，消灭，灭绝，绝种

参考例句：

• The plant is now in danger of extinction.这种植物现在有绝种的危险。
• The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。

3 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

4 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

5 mammoth   

n.长毛象；adj.长毛象似的，巨大的

参考例句：

• You can only undertake mammoth changes if the finances are there.资金到位的情况下方可进行重大变革。
• Building the new railroad will be a mammoth job.修建那条新铁路将是一项巨大工程。

6 rhinoceros   

n.犀牛

参考例句：

• The rhinoceros has one horn on its nose.犀牛鼻子上有一个角。
• The body of the rhinoceros likes a cattle and the head likes a triangle.犀牛的形体像牛，头呈三角形。

7 prehistoric   

adj.（有记载的）历史以前的，史前的，古老的

参考例句：

• They have found prehistoric remains.他们发现了史前遗迹。
• It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。

8 analyze   

vt.分析，解析 (=analyse)

参考例句：

• We should analyze the cause and effect of this event.我们应该分析这场事变的因果。
• The teacher tried to analyze the cause of our failure.老师设法分析我们失败的原因。