Documenting phylogenetic diversity for conservation practice allows elucidation of ecosystem functioning and processes by highlighting the commonality and divergence of species’ functional traits within their evolutionary context. Conserving distinct evolutionary histories has intrinsic value, and the conservation of phylogenetically diverse communities is more likely to preserve distinct or relic evolutionary lineages. We explored the potential for anthropogenic forest fragmentation to act as a selective filter of avian phylogenetic diversity within the community of forest-dependent birds of the critically endangered Indian Ocean Coastal Belt Forest (IOCBF), South Africa. We conducted avian point count surveys during the austral breeding season, and calculated fragmentation metrics of forest structural complexity, patch size and isolation. We constructed a maximum likelihood phylogeny using the combined analysis of two mitochondrial genes and three nuclear markers and measured the influence of the fragmentation metrics on six measures of phylogenetic diversity. Our results indicated that the avian community was variously affected by anthropogenic forest fragmentation, with the different metrics of phylogenetic diversity responding with no definitive overall pattern. However, forest structural complexity emerged as an important metric explaining phylogenetic structuring. While the avian community’s phylogenetic diversity displayed resilience to anthropogenic fragmentation, previous research showed a reduction in functional diversity along the fragmentation gradient. Therefore, we recommend studies that especially aim to guide conservation management, incorporate both phylogenetic and functional diversity measures to sufficiently interrogate communities’ resilience to the threats under investigation.

为保护实践记录系统发育多样性可以通过突出物种在其进化背景下的功能特征的共性和差异性来阐明生态系统的功能和过程。保存不同的进化历史具有内在价值，并且系统发育多样化群落的保护更有可能保存独特的或遗存的进化谱系。我们探索了人为森林破碎化作为南非极度濒危的印度洋海岸带森林 (IOCBF) 依赖森林的鸟类群落中鸟类系统发育多样性的选择性过滤器的潜力。我们在南方繁殖季节进行了鸟类点数调查，并计算了森林结构复杂性、斑块大小和隔离度的破碎指标。我们使用两个线粒体基因和三个核标记的组合分析构建了最大似然系统发育，并测量了碎片化指标对系统发育多样性的六种测量的影响。我们的研究结果表明，鸟类群落受到人为森林破碎化的不同影响，系统发育多样性的不同指标响应没有明确的总体模式。然而，森林结构复杂性成为解释系统发育结构的重要指标。虽然鸟类群落的系统发育多样性显示出对人为碎片化的适应能力，但之前的研究表明，沿着碎片化梯度的功能多样性会降低。因此，我们推荐旨在指导保护管理的研究，