POLAR BEAR SHAKING OFF WATER AFTER SWIMMING

You don’t want to be standing next to a bear when it comes out of the water and shakes its body. It can shed about 70 percent of the water in about four secon...
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You don’t want to be standing next to a bear when it comes out of the water and shakes its body. It can shed about 70 percent of the water in about four seconds! Many mammals having loose skin such as mice, rats, cats, bears, wolves and their dog descendants have this ability. It requires that the skin be loose enough to rotate from side to side substantially more than the skeletal system can do and do so at a speed that is so fast it exceeds the water’s ability to stick to the body. During these skin rotations, the centrifugal forces pulling the water away reaches between 10 and 70 times that of the pull of gravity. These forces are so strong that animals shut their eyes possibly to avoid damaging them.
How fast the skin oscillates back and forth varies with the size of the animal. In bears, it is about 4 times a second. In dogs, it can reach 8 times a second, depending on the breed. In cats, it is about 10 times a second. In mice, it is close to 27 times a second.
Having a fur coat, while it can carry much more water than bare skin, it is an asset to getting rid of it during the skin rotations. The water is pulled down to the outer ends of the hairs and is flicked away most especially at each change in rotation.
Just think of the time and number of wet towels we could save if we had the ability shake off the pound (0.45 kg) of water sticking to our bodies just prior to stepping out of the shower. The photo was taken at the Brookfield Zoo in Chicago.
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