Acoustic signaling is key in mediating mate choice, which directly impacts individual fitness. Because background noise and habitat structure can impair signal transmission, the acoustic space of mixed-species assemblages has long been hypothesized to reflect selective pressures against signal interference and degradation. However, other potential drivers that received far less attention can drive similar outputs on the acoustic space. Phylogenetic niche conservatism and allometric constraints may also modulate species acoustic features, and the acoustic space of communities could be a side-effect of ecological assembly processes involving other traits (e.g., environmental filtering). Additionally, the acoustic space can also reflect the sorting of species relying on public information through extended communication networks. Using an integrative approach, we revisit the potential drivers of the acoustic space by addressing the distribution of acoustic traits, body size, and phylogenetic relatedness in tropical anuran assemblages across gradients of environmental heterogeneity in the Pantanal wetlands. We found the overall acoustic space to be aggregated compared with null expectations, even when accounting for confounding effects of body size. Across assemblages, acoustic and phylogenetic differences were positively related, while acoustic and body size similarities were negatively related, although to a minor extent. We suggest that acoustic partitioning, acoustic adaptation, and allometric constraints play a minor role in shaping the acoustic output of tropical anuran assemblages and that phylogenetic niche conservatism and public information use would influence between-assemblage variation. Our findings highlight an overlooked multivariate nature of the acoustic dimension and underscore the importance of including the ecological context of communities to understand drivers of the acoustic space.

中文翻译：

---

重新审视热带无尾类群落声学相似性的驱动因素

声音信号是调解配偶选择的关键，它直接影响个人健康。由于背景噪声和栖息地结构会损害信号传输，长期以来一直假设混合物种组合的声学空间反映了对信号干扰和退化的选择性压力。然而，其他受到较少关注的潜在驱动因素可以在声学空间上驱动类似的输出。系统发育生态位保守主义和异速生长约束也可能调节物种声学特征，而群落的声学空间可能是涉及其他特征（例如，环境过滤）的生态组装过程的副作用。此外，声学空间还可以通过扩展的通信网络反映依赖公共信息的物种分类。使用综合方法，我们通过解决潘塔纳尔湿地环境异质性梯度中热带无尾猿组合的声学特征、体型和系统发育相关性的分布，重新审视声学空间的潜在驱动因素。我们发现与零预期相比，整体声学空间是聚合的，即使考虑到身体大小的混杂影响。在整个组合中，声学和系统发育差异呈正相关，而声学和体型相似性呈负相关，尽管程度较小。我们建议声学分区、声学适应、和异速生长约束在塑造热带无尾蜥组合的声学输出方面起着次要作用，系统发育生态位保守主义和公共信息使用将影响组合之间的变异。我们的研究结果突出了声学维度被忽视的多元性质，并强调了将社区的生态环境纳入理解声学空间驱动因素的重要性。