Unit of Neuroscience, Department of Medicine and Surgery, University of Parma, Italy.
Department of Anthropology, Baylor University, Waco, TX, USA.
Mol Cell Endocrinol. 2020 Apr 5;505:110721. doi: 10.1016/j.mce.2020.110721. Epub 2020 Jan 28.
Natural selection favors the evolution of mechanisms that optimize the allocation of resources and time among competing traits. Hormones mediate developmental plasticity, the changes in the phenotype that occur during ontogeny. Despite their highly conserved functions, the flexibilities of human hormonal systems suggest a strong history of adaptation to variable environments. Physiological research on developmental plasticity has focused on the early programming effects of stress, the hypothalamus-pituitary-adrenal axis (HPAA) and the hypothalamus-pituitary-gonadal axis (HPGA) during critical periods, when the hormones produced have the strongest influence on the developing brain. Often this research emphasizes the maladaptive effects of early stressful experiences. Here we posit that the HPAA and HPAG systems in human developmental plasticity have evolved to be responsive to complex and dynamic problems associated with human sociality. The lengthy period of human offspring dependency, and its associated brain development and risks, is linked to the uniquely human combination of stable breeding bonds, extensive paternal effort in a multi-male group, extended bilateral kin recognition, grandparenting, and controlled exchange of mates among kin groups. We evaluate an evolutionary framework that integrates proximate physiological explanations with ontogeny, phylogeny, adaptive function, and comparative life history data.
自然选择有利于进化出优化资源和时间在竞争特征之间分配的机制。激素介导发育可塑性，即个体发育过程中表型的变化。尽管它们具有高度保守的功能，但人类激素系统的灵活性表明，它们强烈地适应了变化的环境。关于发育可塑性的生理学研究主要集中在压力的早期编程效应上，即下丘脑-垂体-肾上腺轴（HPAA）和下丘脑-垂体-性腺轴（HPGA）在关键时期，此时产生的激素对发育中的大脑有最强的影响。这项研究通常强调早期压力经历的不良适应效应。在这里，我们假设人类发育可塑性中的 HPAA 和 HPAG 系统已经进化到能够对与人类社会性相关的复杂和动态问题做出反应。人类后代依赖期的漫长时间，以及与之相关的大脑发育和风险，与稳定的繁殖纽带、多雄性群体中广泛的父亲努力、扩展的双边亲属识别、祖辈照顾以及亲属群体之间的伴侣控制交换的独特人类组合有关。我们评估了一个整合了近因生理解释与个体发生、系统发育、适应功能和比较生活史数据的进化框架。
