翻訳と辞書 Words near each other ・ Antanambao, Antsirabe II ・ Antanambaobe ・ Antanambaon'amberina ・ Antanambe ・ Antanambia ・ Antananadava ・ Antananambo ・ Antananarivo ・ Antagonist (album) ・ Antagonist (band) ・ Antagonist (disambiguation) ・ Antagonist A.D. ・ Antagonist Movement ・ Antagonistic Coevolution ・ Antagonistic contradiction ・ Antagonistic pleiotropy hypothesis ・ Antagony ・ Antagoras of Rhodes ・ Antah ・ Antaheen ・ Antaheen Jatra ・ Antahiya ・ Antahkarana ・ Antahpuram ・ Antai-ji ・ Antaifasy ・ Antainambalana River ・ Antaios (Depot) ・ Antaisaka people ・ Antajawi Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Antagonistic pleiotropy hypothesis ： ウィキペディア英語版 Antagonistic pleiotropy hypothesis The antagonistic pleiotropy hypothesis was first proposed by George C. Williams in 1957 as an evolutionary explanation for senescence. Pleiotropy is the phenomenon where one gene controls for more than one phenotypic trait in an organism. Antagonistic pleiotropy is when one gene controls for more than one trait where at least one of these traits is beneficial to the organism's fitness and at least one is detrimental to the organism's fitness. The theme of G.C. William's idea about antagonistic pleiotropy was that if a gene caused both increased reproduction in early life and aging in later life, then senescence would be adaptive in evolution. For example, one study suggests that since follicular depletion in human females causes both more regular cycles in early life and loss of fertility later in life through menopause, it can be selected for by having its early benefits outweigh its late costs.〔Wood, J.W., K.A. O'Conner, D.J. Holman, E. Bringle, S.H. Barsom, M.A. Grimes. 2001. The evolution of menopause by antagonistic pleiotropy. Center for Demography and Ecology, Working Paper.〕 == As a constraint on perfection == Antagonistic pleiotropy is one of the several reasons evolutionary biologists give for organisms never being able to reach perfection through natural selection. Antagonistically pleiotropic genes are the explanation for fitness trade-offs.〔 This means that genes that are pleiotropic control for some beneficial traits and some detrimental traits; thus, if they happen to persist through natural selection, this will prevent organisms from reaching perfection because if they possess the benefits of the gene, they must also possess the imperfections or faults. An example of this would be female rodents that live in a nest with other females and may end up feeding young that are not theirs due to their intense parental drive.〔Alcock, J. 2005. Animal Behavior: eighth edition〕 This strong parental drive will be selected for, but the organisms will still make the mistake of feeding young that are not theirs and mis-allocating their resources. 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「Antagonistic pleiotropy hypothesis」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.