why do polar bears live in cold places
In the High Arctic, the sun sets in October and doesn't rise again until late February. Winter temperatures can plunge to -40` or
and stay that way for days or weeks. The average January and February temperature is. Bears are insulated with two layers of fur and a thick layer of body fat. This provides enough insulation that their body temperature and metabolic rate doesnt change, even when temperatures reach.
To learn more about how polar bears bodies adjust to their climate, seeP. A polar bear's body temperature, 37 C (98. 6 F), is average for mammals. Well known for their slow, plodding gait, polar bears walk at about five to six kilometers (3. 73 miles) per hour. Females with small cubs walk more slowly, about two-and-a-half to four kilometers (1. 55 to 2. 48 miles) per hour. Polar bearsPare able to gallop as fast as a horse over short distances but prefer to amble leisurely.
Norwegian scientist Nils Oritsland showed us that polar bears expend more than twice the energy of most other mammals when walking or running, showing higher-than-average increases in temperature and in oxygen consumption. Walking bears expend 13 times more energy than resting bears. This partly explains their preference for still-hunting, which usually involves a long, patient wait for a seal to surface at a breathing hole in the sea ice.
Polar bears are natural sprinters and can run as fast as 40 kilometers per hourbut only for short distances. Younger, leaner bears are the best runners. They can cover two kilometers without stopping, whereas older, larger bears will quickly overheat.
- Views: 33
why do we have different climate zones
why do polar bears have thick white fur
why do polar bears have short legs
why do polar bears live in the north pole
why do polar bears have black noses