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（Selection）是自然界的核心过程。尽管学界对自然选择的强度与作用形式的认知已有所深化，但对自然界中自然选择的时间动态仍缺乏系统性认知。本研究整合了来自野生种群研究的自然选择时间重复观测数据集，以梳理当前我们对自然选择时间动态已知与未知的内容。该数据集涵盖89项研究的5519条自然选择强度估计值，包含直接选择、间接选择以及线性选择与非线性选择的相关估计。其中形态学性状以及以脊椎动物为研究对象的文献占比较高，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，自然选择强度往往年际间存在显著波动，不过选择系数的随机抽样误差可能会对这类波动幅度的估计结果引入偏差；其二，自然选择的作用方向频繁发生改变；其三，自然选择的作用形式大概率频繁变化，但量化难度相对更高。尽管目前鲜有研究阐明自然选择强度、作用方向及形式随时间变化的潜在因果机制，但气候波动驱动的环境条件变化似乎是较为普遍且关键的影响因素。