Adaptation

If an animal is moved from its home in the tropics to a cold climate, it will die if it is not kept warm. And animals accustomed to cold climates will die if they are moved to the tropics. Many plants, too, will die if they are removed from the place where they normally grow and are transplanted into an unfamiliar soil. Almost every species is adapted to life in a particular place by its organs and their functions and by its permanent habits. The specialized adaptation has great advantages, for it enables many organisms to survive under different conditions. It also has disadvantages, for it means that the life of most species is controlled by local conditions.

Living things are not scattered over the earth at random; most species have definite habits or living places. Ecology is the study of how organisms live in their environment. This means finding out how an organism survives and reproduces in certain surroundings. By environment we mean not only the soil and the climate but also the living things of the same species and other species, plant or animal.

Most living things are slaves to their environment. Some can alter certain features of their environment to suit themselves; a beaver, for example, can make ponds by building dams; many birds and insects can build elaborate nests to provide shelter for their young. But these skills are restricted and highly specialized. Most organisms must adapt their bodies to fit in with their surroundings, and since they can adapt only for particular surroundings they are found only in places where they can live successfully with the least effort.

Plants find these favorable places by trial and error. The wind carries their seeds and spores over great distances. If the seeds land in a favorable environment they grow and reproduce. If they are deposited in an unfavorable environment they die. Animals, on the other hand, search until they find a favorable environment.