国产丝袜在线精品丝袜|在线A毛片免费视频观|日韩精品久久久一区二区|亚洲成在人网站天堂直播|99在线精品66视频无码|亚洲欧美不卡视频在线播放|国产精品久久久久久免费一级|久久精品国产亚洲AV香蕉软件

Cow might soon be the world's largest land mammal: study

Source: Xinhua| 2018-04-23 17:51:32|Editor: ZX
Video PlayerClose

NEW YORK, April 23 (Xinhua) -- Due to the spread of human activities around the world, the cow could be left as the biggest land mammal on Earth in just a few centuries, a new study has found.

The study, published in the journal Science, examines the trends of extinction of large mammals over 125,000 years.

The spread of hominims since thousands of years ago coincided with the extinction of megafauna such as the mammoth and the glyptodon, an armadillo-like creature with the size of a car, as such big animals were usually targeted by humans for meat, according to the study.

"There is a very clear pattern of size-biased extinction that follows the migration of hominims out of Africa," the study's lead author, Flisa Smith of the University of New Mexico, was quoted by the Guardian as saying.

In North America, the mean body mass of land mammals has dropped from 98 kg to 7.6 kg since the arrival of humans.

If such a trend continues, "the largest mammal on Earth in a few hundred years may well be a domestic cow at about 900 kg," the researcher concluded.h That would mean the extinction of elephants, giraffes and hippos, among others.

Despite the conservation efforts, Smith pointed out that the populations of large land mammals were falling and "declining population is the trajectory to extinction."

The world's last male northern white rhino named Sudan died in Kenya in March.

TOP STORIES
EDITOR’S CHOICE
MOST VIEWED
EXPLORE XINHUANET
010020070750000000000000011100001371312111