研究人员评估了从1960年到2020年的5025个集合时间序列中六个类群的体型变化率。利用普赖斯方程将这一变化划分为物种内的体型变化和成分变化，研究人员发现体型随时间的推移普遍减小，这主要是由鱼类驱动的，而其他类群的模式则更加多变。
研究人员发现，与物种内变化趋势相比，集合体组成的变化对体型变化的影响更大，但这两个部分在幅度和方向上都有很大差异。随着体型的减小和丰度的增加，集合体的生物量保持相当稳定。
据悉，生物对全球变化的反应包括生物特征的定向转变。体型是决定人口统计率和生态系统功能的综合性状，据认为在人类世中体型正在缩小。
附：英文原文
Title: Widespread shifts in body size within populations and assemblages
Author: Inês S. Martins, Franziska Schrodt, Shane A. Blowes, Amanda E. Bates, Anne D. Bjorkman, Viviana Brambilla, Juan Carvajal-Quintero, Cher F. Y. Chow, Gergana N. Daskalova, Kyle Edwards, Nico Eisenhauer, Richard Field, Ada Fontrodona-Eslava, Jonathan J. Henn, Roel van Klink, Joshua S. Madin, Anne E. Magurran, Michael McWilliam, Faye Moyes, Brittany Pugh, Alban Sagouis, Isaac Trindade-Santos, Brian J. McGill, Jonathan M. Chase, Maria Dornelas
Issue&Volume: 2023-09-08
Abstract: Biotic responses to global change include directional shifts in organismal traits. Body size, an integrative trait that determines demographic rates and ecosystem functions, is thought to be shrinking in the Anthropocene. Here, we assessed the prevalence of body size change in six taxon groups across 5025 assemblage time series spanning 1960 to 2020. Using the Price equation to partition this change into within-species body size versus compositional changes, we detected prevailing decreases in body size through time driven primarily by fish, with more variable patterns in other taxa. We found that change in assemblage composition contributes more to body size changes than within-species trends, but both components show substantial variation in magnitude and direction. The biomass of assemblages remains quite stable as decreases in body size trade off with increases in abundance.
DOI: adg6006
Source: https://www.science.org/doi/full/10.1126/science.adg6006