Journal of Animal Ecology最新文献

Individual organisms can function as ecosystems inhabited by symbionts. Symbionts may interact with each other in ways that subsequently influence their hosts positively or negatively, although the details of how these interactions operate collectively are usually not well understood. Vane-dwelling feather mites are common ectosymbionts of birds and are proposed to confer benefits to hosts by consuming feather-degrading microbes. However, it is unknown whether these mites exhibit generalist or selective diets, or how their dietary selection could potentially impact their symbiotic functional nature. In this study, we conducted 16S rDNA and ITS1 amplicon sequencing to examine the microbial diet of feather mites. We characterized and compared the diversity and composition of bacteria and fungi in the bodies of mites living on feathers of the Prothonotary Warbler, Protonotaria citrea, to microbial assemblages present on the same feathers. We found less diverse, more compositionally similar microbial assemblages within mites than on feathers. We also found that mites were resource-selective. Based on the identity and known functions of microbes found within and presumably preferred by mites, our results suggest that these mites selectively consume feather-degrading microbes. Therefore, our results support the proposition that mites confer benefits to their hosts. This study provides insight into symbioses operating at multiple biological levels, highlights the ecological and evolutionary importance of the synergistic interactions between species, and greatly expands our understanding of feather mite biology.

1. Differential vulnerability to heatwaves may affect community dynamics in a changing climate. In temperate regions, this vulnerability to heatwaves depends on the interactions between seasonal temperature fluctuations and the capacity to rapidly shift thermal performance curves. 2. Here we investigate how these dynamics affect the vulnerability of two ecologically important copepod congeners, Acartia tonsa and A. hudsonica, to heatwaves of different durations. Using a combination of field observations and simulated laboratory heatwave experiments, we uncover strong seasonal variation in the performance curves of A. tonsa but not A. hudsonica. This translated to species-specific seasonal patterns of vulnerability to heatwaves, with increased vulnerability in A. hudsonica. 3. By reducing parental stress during simulated heatwaves, seasonal performance curve shifts likely reduced indirect, transgenerational effects of these events on offspring performance in A. tonsa. 4. Our results illustrate how different levels of seasonal variation in thermal performance curves will affect population persistence in a changing climate.

Research Highlight: Knutie, S., Bahouth, R., Bertone, M., Webb, C., Mehta, M., Nahom, M., Barta, R., Ghai, S., Love, A., Horan, S., Soldo, A., Cochrane, E., Bartholomew, J., Cowan, E., Bjerke, H., Balenger, S., Butler, M., Cornell, A., Kennedy, A., Rolland, V., Schultz, E., Stanback, M., Taff, C., Albery, G. (2024). Understanding spatiotemporal effects of food supplementation on host–parasite interactions using community-based science. Journal of Animal Ecology. https://doi.org/10.1111/1365-2656.14155. Wildlife have become increasingly dependent on anthropogenic food supplementation, resulting in altered nutritional intake and inter- and intraspecific interactions. Subsequently, supplemental feeding can affect both the immunological function of individuals and transmission dynamics among individuals and species. The magnitude of the effect supplemental feeding has on disease is likely to vary across time and space with the nutritional demands of hosts. However, the broad temporal or spatial scale effects of supplementation are poorly understood. Recently, Knutie et al. (2024) introduced their citizen science program, the Nest Parasite Community Project, a broadscale coordinated effort by scientists and the public to monitor box nesting wild birds and their ectoparasites across the eastern United States. The authors amassed an impressive 4-year data set with hundreds of nests spanning the entire US breeding range of Eastern bluebirds (Sialia sialis). In the first study to come from the project, the authors demonstrate that the effects of food supplementation on host–parasite interactions vary across time and space and do not consistently influence host–parasite outcomes, highlighting that host–parasite interactions are often context dependent and influenced by many environmental factors (e.g. weather and habitat quality). The authors also found that supplemental feeding increases host fitness, regardless of parasitism. The study provides strong evidence that citizen science projects can help broaden our understanding of how human food sources influence wildlife disease in various environmental contexts.