All animals have certain features that help them "fit in" with their surroundings. This is known as animal adaptation. Having the ability to adapt to the environment and its changes is important for an animal's survival. Many adaptations are physical. For example, fish have fins to help them swim and gills that allow them to breathe underwater. Polar bears have several layers of fat so that each can withstand the cold Arctic temperatures. Without these special physical traits, they would have difficulty surviving. Physical adaptations help animals get their nourishment and protect themselves. Adaptations can be organized into six categories.
At one time, giraffes came in a variety of neck lengths. Some giraffes had much shorter necks than modern giraffes. The giraffes with shorter necks couldn’t compete with long-necked giraffes. Food supplies are limited so animals must compete for them with other species and like animals. Unlike the giraffes with long necks, short-necked giraffes couldn’t reach leaves and twigs up high as well as the ones closer to the ground. Because many animals could eat the low-lying vegetation, fewer short-necked giraffes got enough to eat. Over generations, giraffes with longer necks grew stronger and healthier. The long-necked giraffes had more and more babies that, like their parents, inherited long necks and were better able to survive when food was scarce; no other animal could reach the high leaves as well as they could. Over time, more and more short-necked giraffes died before they could reproduce more short-necked babies. Eventually, only long-necked giraffes were born. This process of change, called “natural selection,” happens in all species.
Structural Adaptation involves the physical characteristics of the animal such as its shape, size, teeth, paw size, markings/colour, curved peaks, ear size, feathers,scales etc. How do these traits affect the animal's survival in its environment? Example: The polar bear, as mentioned has layers of fat to keep warm. They also have what appears to be white hair which blends in with the ice and snow of their environment. The hair on Polar bears is in fact transparent and the skin underneath is black. This is so the heat from the sun warms the bear since the black skin absorbs the sunrays. The bear's paws are oversize which lets them walk on top of the snow very much like you wearing snowshoes.
Behavioural Adaptations involve the activities animals do to keep themselves alive. These behaviours are either taught to them by their parents or they are born with them and are referred to as instinctive. Rabbits freeze and don't move, opossums play dead, rhinoes charge, the rattlesnake rattles while others just run away.
Mimicry is the ability to mimic another animal or something else. Some animals have the ability to sound, look and act like other animals. This fools their predators into thinking they are not who they are suppose to be. Others can look just like their surroundings. Some flies, beetles and moths mimic bees and snakes will mimic other more poisonous snakes. The tree frog and walking stick are totally camouflaged because they are able to mimic their surroundings.
Hibernation is considered an adaptation. When food is scarce and temperatures threatening, bears, bats and snakes have the ability to go into a deep sleep for several months at a time. Their body metabolism slows down (heartbeat, breathing), and they survive off of their own body fat.
Migration is the final adaptation. Here, animals move from one area to another and then back again. Why? (better food, better climate, safer area to live in and raise young)