Limits to Natural Selection

Organisms that are well-adapted to their environment are more likely to survive and reproduce. However, natural selection does not lead to perfectly adapted organisms. Several factors constrain natural selection.

For one, natural selection can only act upon existing genetic variation. Hypothetically, redtusks may enhance elephant survival ...

Natural selection can produce striking adaptations that closely fit organisms to their environments, such as camouflage that protects butterflies from predatory birds.

However, natural selection does not always lead to ideal adaptations. Several factors constrain the outcomes of natural selection and prevent organisms from achieving a perf...