Functional traits—not nativeness—shape the effects of large mammalian herbivores on plant communities

Large mammalian herbivores (megafauna) have experienced extinctions and declines since prehistory. Introduced megafauna have partly counteracted these losses yet are thought to have unusually negative effects compared to native megafauna. Using a meta-analysis of 3,995 plot-scale plant abundance and diversity responses from 221 studies, we found no evidence that megafauna impacts were shaped by nativeness, ‘invasiveness’, ‘feralness’, coevolutionary history, or functional and phylogenetic novelty. Nor was there evidence that introduced megafauna facilitate introduced plants more than native megafauna. Instead, we found strong evidence that functional traits shaped megafauna impacts, with larger-bodied and bulk-feeding megafauna promoting plant diversity. Our work suggests that trait-based ecology provides better insight into interactions between megafauna and plants than concepts of nativeness., Literature screening and digitization This meta-analysis was part of a larger effort to understand megafauna impacts on multiple facets of ecosystems (e.g. including soil nutrients, invertebrates, etc). This ensured that the dataset included plant responses that were also measured in studies focused on other response variables (e.g., spider diversity). We searched Web of Science with a string of search terms that included the common names and Latin genera of all terrestrial mammalian megafauna species (common names from HerbiTraits v1.2 (Lundgren et al. 2021)) separated with an ‘OR’ operand, along with the following search terms: “disturb*, graz*, brows*, impact*, effect, affect, disrupt, facilitate, invasi*, ecosystem*, vegetat*, plant*, fauna*, reptil*, amphib*, bird*, rodent*, fish*, invertebrat*, insect*, soil*, carbon, climate, albedo, river*, riparian, desert*, forest*, tundra, decomposition, grassland*, savanna*, chaparral, scrub, shrub, diversity, heterogeneity, extinction, rich..., R version 4.2.1 as well as a variety of packages, including data.table, metafor, multcomp, ggplot2, broom, tidyr, and dplyr., # Data for Functional traits - not nativeness - shape the effects of large mammalian herbivores on plant communities --- This dataset consists of meta-analytic data on plant diversity and abundance responses to mammalian megafauna (>45 kg). This data can be used (as in manuscript) to assess whether there are differences between introduced and native megafauna in their effects on plants and to assess how megafauna functional traits, environmental variables, and so on, influence megafauna effects on plants. ## Description of the Data and file structure This repository includes the following data files. Note that NA and blank cells are considered equivalent in all csv files. 'Plant_Abundance.csv' = Each row is an observed effect of megafauna on plant abundance. 'Plant_Diversity.csv' = Each row is an observed effect of megafauna on plant diversity. This dataset and 'Plant_Abundance.csv' have the same columns but are separated for convenience. 'Model_Comparison_Guide.csv' = This dat...大型植食性哺乳动物（megafauna，巨型动物群）自史前时代起便经历了物种灭绝与种群衰退。外来引入的巨型动物群在一定程度上抵消了这些种群损失，但学界普遍认为，相较于本土巨型动物群，外来巨型动物群会带来异常显著的负面影响。本研究针对221项研究中的3995个样地尺度植物多度与多样性响应数据开展荟萃分析（meta-analysis），结果显示，并无证据表明巨型动物群的生态影响受其本土性、‘入侵性’、‘野生性’、协同进化历史，或功能与系统发育新颖性所调控。亦无证据表明，外来巨型动物群对外来植物的促进作用强于本土巨型动物群。与之相反，本研究获得了充分证据，证明功能性状才是调控巨型动物群生态影响的核心因素：体型更大、取食量大的巨型动物群能够提升植物多样性。本研究表明，相较于本土性相关概念，基于性状的生态学能更深入地阐释巨型动物群与植物间的互作关系。 ### 文献筛选与数字化 本次荟萃分析是一项更大规模研究的组成部分，该研究旨在探究巨型动物群对生态系统多维度的影响（例如土壤养分、无脊椎动物等）。这一研究设计确保了本数据集涵盖的植物响应数据，同时也出现在针对其他响应变量（如蜘蛛多样性）的相关研究中。本研究通过一系列检索式在Web of Science数据库中开展文献检索：检索式包含所有陆生哺乳类巨型动物群物种的通用名与拉丁属名（通用名取自HerbiTraits v1.2（Lundgren等，2021）），各名称间以‘OR’逻辑运算符连接，同时搭配以下检索词：“disturb*、graz*、brows*、impact*、effect、affect、disrupt、facilitate、invasi*、ecosystem*、vegetat*、plant*、fauna*、reptil*、amphib*、bird*、rodent*、fish*、invertebrat*、insect*、soil*、carbon、climate、albedo、river*、riparian、desert*、forest*、tundra、decomposition、grassland*、savanna*、chaparral、scrub、shrub、diversity、heterogeneity、extinction、rich...”。本研究使用R语言版本4.2.1及一系列扩展包完成数据分析，包括data.table、metafor、multcomp、ggplot2、broom、tidyr与dplyr。 # 功能性状而非本土性调控大型植食性哺乳动物对植物群落的影响 --- 本数据集包含针对体重超过45千克的哺乳类巨型动物群的植物多样性与多度响应的荟萃分析数据。如本研究手稿中所示，该数据集可用于评估外来与本土巨型动物群对植物的影响是否存在差异，同时可用于探究巨型动物群功能性状、环境变量等因素如何调控其对植物的生态影响。 ## 数据与文件结构说明 本仓库包含以下数据文件。请注意：所有CSV文件中，NA值与空白单元格均视为等效值。 `Plant_Abundance.csv`：每一行代表一项巨型动物群对植物多度的观测效应。 `Plant_Diversity.csv`：每一行代表一项巨型动物群对植物多样性的观测效应。该数据集与`Plant_Abundance.csv`拥有相同的列结构，仅为便于使用而拆分存储。 `Model_Comparison_Guide.csv`：本数据文件……