Scientists from the United States found a mouse at an altitude of 6.7 km. This is a record height of residence for any species of mammals on Earth.
In 2019, researchers reported that they had found a mammal that is capable of living at the world’s highest altitude. It turned out to be a large-leaved yellow mouse, which was spotted at the top of Mount Llullaillaco, the world’s highest historically active volcano located between Argentina and Chile.
Scientists did not expect mammals to live so high. At an altitude of 6.1 km, there is no vegetation and the mice have nothing to eat. At the same time, it rarely rains on the edge of the Atacama Desert, and the temperature sometimes drops below minus 24 degrees Celsius. “This environment is very hostile and we find it difficult to understand how and why mice live here permanently,” said Jay Storz, a biologist at the University of Nebraska.
Intrigued by this discovery, Storz organized another expedition to the volcano in February specifically to search for rodents. He came across another mouse, but she lived even higher – at an altitude of 6.7 km. This is a record figure for mammals.
The research, published on BioRxiv, is the beginning of a scientific quest to understand how these animals adapt to and survive these debilitating conditions. Their findings could help scientists understand how other creatures adapt to extreme conditions, and may even have medical uses for people with low oxygen levels.
Most of the mice, belonging to four different species, were caught using small traps during the expedition in February, so scientists are now studying them in the laboratory. This is necessary because it is almost impossible to conduct experiments at the top of the mountain – there is little oxygen there and severe storms often occur.