AimThe species that compose local communities possess unique sets of functional and ecological traits that can be used as indicators of biotic and abiotic variation across space and time. Body size is a particularly relevant trait because species with different body sizes typically have different life history strategies and occupy distinct niches. Here we used the body sizes of non‐volant (i.e., non‐flying) terrestrial mammals to quantify and compare the body size disparity of mammal communities across the globe.LocationGlobal.Time PeriodPresent.Major Taxa StudiedNon‐volant terrestrial mammals.MethodsWe used IUCN range maps of 3982 terrestrial mammals to identify 1876 communities. We then combined diet data with data on climate, elevation and anthropogenic pressures to evaluate these variables' relative importance on the observed body size dispersion of these communities and its deviation from a null model.ResultsDispersion for these communities is significantly greater than expected in 54% of communities and significantly less than expected in 30% of communities. The number of very large species, continent, range sizes, diet disparity and annual temperature collectively explain > 50% of the variation in observed dispersion, whereas continent, the number of very large species, and precipitation collectively explain > 30% of the deviation from the null model.Main ConclusionsClimate and elevation have minimal predictive power, suggesting that biotic factors may be more important for explaining community body size distributions. However, continent is consistently a strong predictor of dispersion, likely due to it capturing the combined effects of climate, size‐selective human‐induced extinctions and more. Overall, our results are consistent with several plausible explanations, including, but not limited to, competitive exclusion, unequal distribution of resources, within‐community environmental heterogeneity, habitat filtering and ecosystem engineering. Further work focusing on other confounding variables, at finer spatial scales and/or within more causal frameworks is required to better understand the driver(s) of these patterns.

中文翻译：

---

研究非飞行陆生哺乳动物群落体型差异的生物和非生物驱动因素


目标组成当地群落的物种拥有独特的功能和生态特征，可以用作跨空间和时间的生物和非生物变异的指标。体型是一个特别相关的特征，因为不同体型的物种通常有不同的生活史策略并占据不同的生态位。在这里，我们使用非飞行（即非飞行）陆生哺乳动物的体型来量化和比较全球哺乳动物群落的体型差异。位置全球。时间段当前。研究的主要分类群非飞行陆生哺乳动物。方法我们使用 IUCN 3982 种陆地哺乳动物的分布范围图，以确定 1876 个群落。然后，我们将饮食数据与气候、海拔和人为压力数据结合起来，评估这些变量对观察到的这些群落体型离散度的相对重要性及其与零模型的偏差。结果这些群落的离散度显着大于预期（54%）的社区，并且 30% 的社区明显低于预期。非常大的物种数量、大陆、分布范围、饮食差异和年气温共同解释了观察到的分散变化的 > 50%，而大陆、非常大的物种数量和降水共同解释了观测到的分散度的 > 30%与零模型的偏差。主要结论气候和海拔的预测能力极小，这表明生物因素对于解释群落体型分布可能更为重要。然而，大陆始终是扩散的有力预测因素，可能是因为它捕捉到了气候、规模选择性人类引起的灭绝等的综合影响。 总的来说，我们的结果与几个看似合理的解释是一致的，包括但不限于竞争排斥、资源分配不平等、社区内环境异质性、栖息地过滤和生态系统工程。需要在更精细的空间尺度和/或更多的因果框架内关注其他混杂变量，以更好地理解这些模式的驱动因素。