VOA慢速英语2020--公象毕竟也不孤独（在线收听）

Male Elephants Are Not Loners After All

A group of elephants walk across an area in northern Botswana. Their ears move and their trunks sometimes touch the ground. As they pass, a camera, hidden in low plants, records the presence of each elephant.

What is special about this group? It is only males.

Female elephants are known to form tight family groups that are led by experienced females.

Males were thought to be loners - creatures that are often alone. They often leave their mother's herd when they reach 10 to 20 years of age.

However, a new study shows that young males are not always loners.

Younger male elephants were seen following older males as they traveled from place to place. The findings support other research that suggests older males play an important part in elephants' complex society.

The study was published recently in Scientific Reports. Researchers studied videos of 1,264 sightings of male African elephants. The elephants were traveling toward Botswana's Boteti River in 2017 and 2018. They found that younger males rarely traveled alone. Older males most often led groups of mixed ages.

Diana Reiss is the director of the Animal Behavior and Conservation Program at Hunter College. Reiss was not involved in the new study.

"Mature male elephants often take a position at the front of the line when they are leading the group," she said.

Reiss added, "In human societies, grandparents are valued because they make really important contributions — helping with childcare and passing down knowledge gained over decades...We're now learning this pattern is also true for some other long-lived mammals, including dolphins, whales and elephants."

This is the first study of African savannah elephants of its kind. A 2019 paper also used cameras to find similar male group actions among Asian elephants.

Scientists have long known more about breeding herds of female elephants, said Connie Allen, a biologist at the University of Exeter in Britain.

Allen was a co-writer of the new paper. She added that males have complex social lives, and their groupings are not only shaped by family ties.

When several young male elephants were introduced into a park in Pilanesberg, South Africa in the mid-1990s, they were very aggressive. They killed 40 white rhinoceros. But their behavior changed after six older male elephants were added to the park.

"In some way, the older males create order," said Carl Safina, an ecologist at Stony Brook University. Safina also was not involved in the new study.

Mature male elephants are larger and have longer tusks – a kind of large tooth that sticks out of the mouth. They are often the target of hunters – both legal and illegal – in Africa.

Allen said that future conservation plans should consider the part that older males play. Males are more mysterious, she said, "but it turns out they aren't such loners."

I'm John Russell.

Words in This Story

trunk – n. the long, flexible nose of an elephant

herd – n. a group of animals that live or are kept together

mature – adj. not young : middle-aged or older

contribution – n. the act of giving something : the act of contributing

pattern – n. the regular and repeated way in which something happens or is done

breeding –n. the process by which animals produce and care for their young; related to producing and caring for the young

conservation – n. the protection of animals, plants, and natural resources