The eye is an adaptation.

A biological adaptation is an anatoakemical structure, physiological process or behavioral trait of an organism that has evolved over a period of time by the process of natural selection such that it increases the expected long-term reproductive success of the organism. Image:Menschliches auge. ... Image:Menschliches auge. ... Main articles: Life All organisms (viruses not included) consist of cells, which in turn, are based on a common carbon-based biochemistry. ... Charles Darwin, father of the theory of evolution by natural selection. ... Natural selection is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. ...

Organisms that are adapted to their environment are able to:

• get air, water, food
• cope with physical conditions such as temperature and light
• defend themselves from their natural enemies
• reproduce

Adaptions can be structural or behavioural too. Structural adaptations are special body parts of an organism that help it to survive in its natural habitat, for example, its skin colour, shape and body covering. Behavioural adaptations are special ways an particular organism behaves to survive in its natural habitat. Organisms that are not suitably adapted to their environment will either have to move out of the habitat or die out.

Take the eagle for example. The eagle has a sharp and hooked beak and claws; its body structure is specially designed to swoop down and catch its unwary prey. The sharp beak tears the prey's flesh, while the claws grip the prey tightly.

See also

Spandrel In the masonry arch, a spandrel or spandril (formerly splaundrel, a word of unknown origin) is the space between two arches. ...