Future biodiversity loss threatens the integrity of complex ecological associations, including among hosts and parasites. Almost half of primate species are threatened with extinction, and the loss of threatened hosts could negatively impact parasite associations and ecosystem functions. If endangered hosts are highly connected in host–parasite networks, then future host extinctions will also drive parasite extinctions, destabilizing ecological networks. If threatened hosts are not highly connected, however, then network structure should not be greatly affected by the loss of threatened hosts. Networks with high connectance, modularity, nestedness and robustness are more resilient to perturbations such as the loss of interactions than sparse, nonmodular and non-nested networks. We analysed the interaction network involving 213 primates and 763 parasites and removed threatened primates (114 species) to simulate the effects of extinction. Our analyses revealed that connections to 23% of primate parasites (176 species) may be lost if threatened primates go extinct. In addition, measures of network structure were affected, but in varying ways because threatened hosts have fewer parasite interactions than non-threatened hosts. These results reveal that host extinctions will perturb the host–parasite network and potentially lead to secondary extinctions of parasites. The ecological consequences of these extinctions remain unclear.

This article is part of the theme issue ‘Infectious disease macroecology: parasite diversity and dynamics across the globe’.

未来的生物多样性丧失威胁着复杂生态关联的完整性，包括宿主和寄生虫之间的关联。几乎一半的灵长类物种面临灭绝威胁，受威胁宿主的丧失可能会对寄生虫关联和生态系统功能产生负面影响。如果濒临灭绝的宿主在宿主 - 寄生虫网络中高度连接，那么未来的宿主灭绝也将推动寄生虫灭绝，破坏生态网络的稳定。然而，如果受威胁的主机不是高度连接的，那么网络结构应该不会因受威胁的主机丢失而受到很大的影响。与稀疏、非模块化和非嵌套网络相比，具有高连接性、模块化、嵌套性和鲁棒性的网络对干扰（例如交互丢失）更具弹性。我们分析了涉及 213 种灵长类动物和 763 种寄生虫的相互作用网络，并移除了受威胁的灵长类动物（114 种）以模拟灭绝的影响。我们的分析表明，如果受威胁的灵长类动物灭绝，与 23% 的灵长类寄生虫（176 种）的联系可能会丢失。此外，网络结构的测量也受到了影响，但以不同的方式受到影响，因为受威胁的宿主比未受威胁的宿主具有更少的寄生虫相互作用。这些结果表明，宿主灭绝会扰乱宿主-寄生虫网络，并可能导致寄生虫的二次灭绝。这些灭绝的生态后果仍不清楚。我们的分析表明，如果受威胁的灵长类动物灭绝，与 23% 的灵长类寄生虫（176 种）的联系可能会丢失。此外，网络结构的测量也受到了影响，但以不同的方式受到影响，因为受威胁的宿主比未受威胁的宿主具有更少的寄生虫相互作用。这些结果表明，宿主灭绝会扰乱宿主-寄生虫网络，并可能导致寄生虫的二次灭绝。这些灭绝的生态后果仍不清楚。我们的分析表明，如果受威胁的灵长类动物灭绝，与 23% 的灵长类寄生虫（176 种）的联系可能会丢失。此外，网络结构的测量也受到了影响，但以不同的方式受到影响，因为受威胁的宿主比未受威胁的宿主具有更少的寄生虫相互作用。这些结果表明，宿主灭绝会扰乱宿主-寄生虫网络，并可能导致寄生虫的二次灭绝。这些灭绝的生态后果仍不清楚。

本文是主题问题“传染病宏观生态学：全球寄生虫多样性和动态”的一部分。