Current Biology 17, 2150-2156


Aging and fertility patterns in wild chimpanzees provide insights into the evolution of menopause.

Melissa E. Thompson, James H. Jones, Anne E. Pusey, Stella Brewer Marsden, Jane Goodall, David Marsden, Tetsuro Matsuzawa, Toshisada Nishida, Vernon Reynolds, Yukimaru Sugiyama, Richard W. Wrangham


松沢哲郎 霊長類研究所教授、米国ハーバード大学などからなる研究チームの研究で、野生チンパンジーには閉経後の老年期がなく、人間の女性だけに「おばあさん」期のあることがわかりました。





野生チンパンジーのデータを、ボツワナとパラグアイの採集狩猟民の資料と比較した。人間は25-35歳に繁殖期のピークがあるが、野生チンパンジーではこれが少し早 く始まり、少し長く続く。平坦で長い繁殖期があり、40歳を越えても繁殖し、死ぬまで産み続ける。




Human menopause is remarkable in that reproductive senescence is markedly accelerated relative to somatic aging, leaving an extended postreproductive period for a large proportion of women [1,2]. Functional explanations for this are debated [3,4,5,6,7,8,9,10,11], in part because comparative data from closely related species are inadequate. Existing studies of chimpanzees are based on very small samples and have not provided clear conclusions about the reproductive function of aging females [12,13,14,15,16,17,18,19]. These studies have not examined whether reproductive senescence in chimpanzees exceeds the pace of general aging, as in humans, or occurs in parallel with declines in overall health, as in many other animals [20,21]. In order to remedy these problems, we examined fertility and mortality patterns in six free-living chimpanzee populations. Chimpanzee and human birth rates show similar patterns of decline beginning in the fourth decade, suggesting that the physiology of reproductive senescence was relatively conserved in human evolution. However, in contrast to humans, chimpanzee fertility declines are consistent with declines in survivorship, and healthy females maintain high birth rates late into life. Thus, in contrast to recent claims [16], we find no evidence that menopause is a typical characteristic of chimpanzee life histories.

Thompson ME. , Jones JH. , Pusey AE. , Marsden SBrewer , Goodall J, Marsden D, Matsuzawa T, Nishida T, Reynolds V, Sugiyama Y, Wrangham RW. (2007) Aging and fertility patterns in wild chimpanzees provide insights into the evolution of menopause. Current Biology 17, 2150-2156 , doi: 10.1016/j.cub.2007.11.033