Data from: It's about time: the temporal dynamics of phenotypic selection in the wild

Selection is a central process in nature. Although our understanding of the strength and form of selection has increased, a general understanding of the temporal dynamics of selection in nature is lacking. Here, we assembled a database of temporal replicates of selection from studies of wild populations to synthesize what we do (and do not) know about the temporal dynamics of selection. Our database contains 5519 estimates of selection from 89 studies, including estimates of both direct and indirect selection as well as linear and nonlinear selection. Morphological traits and studies focused on vertebrates were well-represented, with other traits and taxonomic groups less well-represented. Overall, three major features characterize the temporal dynamics of selection. First, the strength of selection often varies considerably from year to year, although random sampling error of selection coefficients may impose bias in estimates of the magnitude of such variation. Second, changes in the direction of selection are frequent. Third, changes in the form of selection are likely common, but harder to quantify. Although few studies have identified causal mechanisms underlying temporal variation in the strength, direction and form of selection, variation in environmental conditions driven by climatic fluctuations appear to be common and important.

自然选择是自然界的核心过程。尽管学界对自然选择的强度与形式的认知已逐步加深，但针对自然界中自然选择的时间动态的系统性理解仍存在空白。在此，我们整合了一项源自野生种群研究的自然选择时间重复观测数据库，以梳理当前我们对自然选择时间动态已知与未知的内容。本数据库涵盖了来自89项研究的5519条自然选择估计值，既包含直接选择与间接选择的估计结果，也涵盖线性选择与非线性选择的估计结果。形态性状以及以脊椎动物为研究对象的文献占比颇高，其余性状与分类类群的占比则相对较低。总体而言，自然选择的时间动态具备三大核心特征：其一，自然选择的强度往往存在显著的年际波动，不过选择系数的随机抽样误差可能会对该波动幅度的估计结果引入偏倚；其二，自然选择的方向频繁发生改变；其三，自然选择的形式大概率会频繁变化，但这类变化更难被量化。尽管鲜有研究阐明自然选择的强度、方向与形式随时间变化的潜在因果机制，但由气候波动驱动的环境条件变化，似乎是较为普遍且重要的影响因素。