Crews Douglas E, Gerber Linda M
Department of Anthropology, School of Public Health, Ohio State University, Columbus, Ohio, USA.
Coll Antropol. 2003 Jun;27(1):7-22.
Aspects of life history, such as processes and timing of development, age at maturation, and life span are consistently associated with one another across the animal kingdom. Species that develop rapidly tend to mature and reproduce early, have many offspring, and exhibit shorter life spans (r-selection) than those that develop slowly, have extended periods of premature growth, mature later in life, reproduce later and less frequently, have few offspring and/or single births, and exhibit extended life spans (K-selection). In general, primates are among the most K-selected of species. A suite of highly derived life history traits characterizes humans. Among these are physically immature neonates, slowed somatic development both in utero and post-natally, late attainment of reproductive maturity and first birth, and extended post-mature survival. Exactly when, why, and through what types of evolutionary interactions this suite arose is currently the subject of much conjecture and debate. Humankind's biocultural adaptations have helped to structure human life history evolution in unique ways not seen in other animal species. Among all species, life history traits may respond rapidly to alterations in selective pressures through hormonal processes. Selective pressures on life history likely varied widely among hominids and humans over their evolutionary history. This suggests that current patterns of human growth, development, maturation, reproduction, and post-mature survival may be of recent genesis, rather then long-standing adaptations. Thus, life history patterns observed among contemporary human and chimpanzee populations may provide little insight to those that existed earlier in hominid/human evolution.
生活史的各个方面，如发育过程和时间、成熟年龄以及寿命，在动物界中始终相互关联。发育迅速的物种往往早熟并早早繁殖，后代众多，寿命较短（r选择），而发育缓慢、有较长的幼年期、成熟较晚、繁殖较晚且频率较低、后代较少和/或单胎生育、寿命较长的物种（K选择）则相反。一般来说，灵长类动物是K选择程度最高的物种之一。一系列高度特化的生活史特征是人类所特有的。其中包括身体上未成熟的新生儿、子宫内和出生后身体发育缓慢、生殖成熟和首次生育较晚，以及成熟后生存期延长。这套特征究竟何时、为何以及通过何种类型的进化相互作用出现，目前是许多猜测和争论的主题。人类的生物文化适应以其他动物物种未见的独特方式塑造了人类生活史的进化。在所有物种中，生活史特征可能通过激素过程对选择压力的变化迅速做出反应。在人类进化史上，人科动物和人类在生活史上受到的选择压力可能差异很大。这表明，当前人类生长、发育、成熟、繁殖和成熟后生存的模式可能是近期才出现的，而非长期适应的结果。因此，当代人类和黑猩猩群体中观察到的生活史模式可能对人科动物/人类进化早期存在的模式提供不了多少见解。
