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Convergent evolution is the independent evolution of similar features in species of different lineages. Convergent evolution creates analogous structures that have similar form or function, but that were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy, from Greek for ''same form''. The recurrent evolution of flight is a classic example of convergent evolution. Flying insects, birds, and bats have all evolved the capacity of flight independently. They have "converged" on this useful trait. Functionally similar features arising through convergent evolution are termed ''analogous'', in contrast to ''homologous'' structures or traits, which have a common origin, but not necessarily similar function.〔 The British anatomist Richard Owen was the first scientist to recognise the fundamental difference between analogies and homologies. Bat and pterosaur wings constitute an example of analogous structures, while the bat wing is homologous to human and other mammal forearms, sharing an ancestral state despite serving different functions. The opposite of convergent evolution is divergent evolution, whereby related species evolve different traits. On a molecular level, this can happen due to random mutation unrelated to adaptive changes; see long branch attraction. Convergent evolution is similar to, but distinguishable from, the phenomena of parallel evolution. Parallel evolution occurs when two independent but similar species evolve in the same direction and thus independently acquire similar characteristics—for instance gliding frogs have evolved in parallel from multiple types of tree frog. ==Causes== In morphology, analogous traits will often arise where different species live in similar ways and/or similar environment, and so face the same environmental factors. When occupying similar ecological niches (that is, a distinctive way of life) similar problems lead to similar solutions.〔(Online Biology Glossary ).〕 In biochemistry, physical and chemical constraints on mechanisms cause some active site arrangements to independently evolve multiple times in separate enzyme superfamilies (for example, see also catalytic triad). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「convergent evolution」の詳細全文を読む スポンサード リンク
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