Abstract Life history theory has become a prominent framework in the evolutionary social sciences, and the concept of trade-offs, the cornerstone of life history theory in studies on non-human taxa, has likewise been widely adopted. Yet, human life history research often assumes trade-offs without demonstrating them. This is not surprising given the practical difficulties in measuring trade-offs in long-lived animals, like humans. Four main methods are used to demonstrate trade-offs: phenotypic correlations, experimental manipulations, genetic correlations and correlated responses to selection. Here, I discuss challenges with these methods along with potential solutions. For example, individual heterogeneity within a population in quality or access to resources can mask underling trade-offs, and this can be accounted for by careful experimental manipulation or proper statistical treatment of observational data. In general, trade-offs have proven more difficult than expected to measure, and evidence across species is mixed, but strong evidence exists in some cases. I use the key trade-off between reproduction and survival to exemplify methods, challenges and solutions, and review the mixed evidence for a cost of reproduction in humans. I conclude by providing directions for future research. Promising avenues are opening thanks to recent advances in quantitative genetic and genomic methods coupled with the availability of high-quality large-scale datasets on humans from different populations, allowing the study of the evolutionary implications of life history trade-offs in humans.

中文翻译：

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在人类生活史研究中衡量权衡的挑战

摘要 生命史理论已经成为进化社会科学的一个重要框架，权衡的概念作为生命史理论在非人类类群研究中的基石也被广泛采用。然而，人类生活史研究经常假设权衡而不证明它们。鉴于衡量长寿动物（如人类）的权衡存在实际困难，这并不奇怪。四种主要方法用于证明权衡：表型相关性、实验操作、遗传相关性和对选择的相关反应。在这里，我将讨论这些方法的挑战以及潜在的解决方案。例如，人群中个体在质量或资源获取方面的异质性会掩盖潜在的权衡，这可以通过仔细的实验​​操作或对观察数据的适当统计处理来解释。总的来说，权衡取舍已证明比预期更难衡量，跨物种的证据不一，但在某些情况下存在强有力的证据。我使用繁殖和生存之间的关键权衡来举例说明方法、挑战和解决方案，并审查人类繁殖成本的混合证据。最后，我为未来的研究提供方向。由于数量遗传和基因组方法的最新进展以及来自不同人群的高质量大规模数据集的可用性，有希望的途径正在开辟，从而允许研究人类生活史权衡的进化影响。