Kuhle Barry X
Department of Psychology, Dickinson College, P.O. Box 1773, Carlisle, PA 17013, USA.
Maturitas. 2007 Aug 20;57(4):329-37. doi: 10.1016/j.maturitas.2007.04.004. Epub 2007 Jun 1.
The "grandmother hypothesis" proposes that menopause evolved because ancestral middle-aged women gained greater reproductive success from investing in extant genetic relatives than from continuing to reproduce [Williams GC. Pleiotropy, natural selection, and the evolution of senescence. Evolution 1957;11:398-411]. Because middle-aged women faced greater risks of maternal death during pregnancy and their offspring's infancy than did younger women, offspring of middle-aged women may not have received the needed level of prolonged maternal investment to survive to reproductive age. I put forward the "absent father hypothesis" proposing that reduced paternal investment linked with increasing maternal age was an additional impetus for the evolution of menopause. Reduced paternal investment was linked with increasing maternal age because men died at a younger age than their mates and because some men were increasingly likely to defect from their mateships as their mates aged. The absent father hypothesis is not an alternative to the grandmother hypothesis but rather a complement. It outlines an additional cost--reduced paternal investment--associated with continued reproduction by ancestral middle-aged women that could have been an additional impetus for the evolution of menopause. After reviewing additional explanations for the origin of menopause ("patriarch hypothesis," "lifespan-artifact" hypotheses), I close by proposing a novel hypothesis for the ontogeny of menopause. According to the "adaptive onset hypothesis," the developmental timing of menopause is a conditional reproductive strategy in which a woman's age at onset is influenced by the likelihood that any children she could produce would survive to reproductive age. Twelve variables predicted to be associated with age at onset and evidence that bears upon the predictions is discussed.
“祖母假说”提出，更年期的进化是因为相比继续生育，远古时期的中年女性通过对现存基因亲属的投入获得了更大的繁殖成功[威廉姆斯·G·C。多效性、自然选择与衰老的进化。《进化》1957年；11:398 - 411]。由于中年女性在怀孕和其后代婴儿期面临的孕产妇死亡风险比年轻女性更大，中年女性的后代可能没有得到存活至生育年龄所需的长期母亲投入水平。我提出了“父亲缺失假说”，认为与母亲年龄增加相关的父亲投入减少是更年期进化的另一个推动力。父亲投入减少与母亲年龄增加相关，是因为男性比其配偶更早死亡，还因为随着配偶年龄增长，一些男性越来越有可能抛弃他们的配偶关系。父亲缺失假说并非祖母假说的替代，而是一种补充。它概述了远古时期中年女性继续生育所带来的额外代价——父亲投入减少，这可能是更年期进化的另一个推动力。在回顾了关于更年期起源的其他解释（“父权假说”、“寿命假象”假说）后，我最后提出了一个关于更年期个体发生的新假说。根据“适应性发病假说”，更年期的发育时间是一种有条件的繁殖策略，其中女性发病的年龄受她可能生育的任何孩子存活至生育年龄的可能性影响。讨论了预计与发病年龄相关的12个变量以及支持这些预测的证据。
