Adaptation of the Polar Bear

Adaptation of the Polar Bear

Adaptation of the Polar Bear

Polar bears belong to the bear family, but have evolved so much that they are considered their own species. Through research and fossil records it has been determined that they are most closely related to the brown bear. “Scientists believe polar bears descended from a group of brown bears that became isolated by glaciers in an area near Siberia” (Polar Bears International, 2012). Polar bears of today are superbly adapted to the Artic.

There are many ways that polar bears have adapted to live in the artic. “These bears underwent a rapid series of evolutionary changes in order to survive—from changes in the color of their fur and shape of their body to keener senses to sharper teeth” (Polar Bears International, 2012). Their main habitat is the sea and its sea-ice surface. The temperature can plunge to -40 degrees and the bears have developed a dense undercoat that not only lets them blend into their environment but also helps to keep them warm (Figure 1). The clear long hair shafts tunnel the sun’s rays to the black skin and the four inch layer of fat just under the skin, which absorbs heat. These characteristics are vastly different to the brown bear it is thought to evolve from. Brown bears have varying brown fur coats that differ in lengths and coarseness due to season. The polar bears body shape is also different. It is larger than the brown bear and also round in shape. These qualities also help to minimize heat loss.

Polar bears are at the top of the food chain in the Arctic. Although polar bears have been known to be opportunistic eaters, their primary diet consists of ring seals. “It will also hunt other types of seals and occasionally walrus, belugas and narwhals” (Canadian Geographic, 2012). In Fig. 1, the polar bears teeth are long sharp canines and flattened grinding molars. These are very different from brown bears and these differences allow the polar bears to break through...