Features evolved for one purpose may be co-opted for a different one, as when the insulating feathers of dinosaurs were co-opted for bird flight.Īdaptation is a major topic in the philosophy of biology, as it concerns function and purpose ( teleology). In mimicry, species evolve to resemble other species in Müllerian mimicry this is a mutually beneficial co-evolution as each of a group of strongly defended species (such as wasps able to sting) come to advertise their defenses in the same way. Often, two or more species co-adapt and co-evolve as they develop adaptations that interlock with those of the other species, such as with flowering plants and pollinating insects.
Charles Darwin proposed instead that it was explained by natural selection.Īdaptation is related to biological fitness, which governs the rate of evolution as measured by change in allele frequencies. In 18th and 19th century natural theology, adaptation was taken as evidence for the existence of a deity. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Secondly, it is a state reached by the population during that process. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. In biology, adaptation has three related meanings.