Ecology最新文献

Microorganisms are ubiquitous in nature, representing a significant portion of global biodiversity and playing vital roles in ecosystem functions, biogeochemical cycles, and organismal health. The growing recognition of microbial importance and their potential to address ecological and global challenges has inspired a renewed interest and innovation in microbial ecology. This field has benefited immensely from sequencing technologies that allow scientists to explore diversity at scales previously unimaginable. While the rapid growth of the field has offered significant positive advancements and foreshadows promising potential, there are aspects that need careful consideration. New technology has led to exponential growth in available microbial data, yet not everyone has easy access to sequencing technology, data mining and analysis tools, or the time to acquire new skills. Thus, we are at a crossroads in ensuring that these resources are accessible for all, and that traditional methods of microbiology are still appreciated as tools to progress the field in meaningful ways. As early-career researchers, we want to raise these points as principles for shaping the future of microbial ecology. Here, we outline a vision for a more accessible, united, and responsible microbial ecology field, one with applications equipped to address the needs of both society and the environment. To democratize the field, we advocate to destigmatize microbes and increase awareness of their beneficial roles by integrating microbes into early education. We believe unity and collaboration among microbial ecologists, as well as with professionals and community members in other STEM fields, are essential for advancing the field. Data should be accessible and standardized for collaboration, and greater integration across disciplines is essential to address future ecological challenges effectively and innovatively. It is our responsibility to ensure that we are asking relevant research questions with the potential to engage with socio-environmental issues and prioritize sustainable practices. As a collective field, our research should strive to not only expand scientific knowledge but also support community resilience and policy-making for a sustainable future. Together, this vision will promote a more equitable, diverse, and collaborative future for microbial ecology; and has applications for the broader ecology field.

About half of all plant species rely on animals such as scatter-hoarding small mammals for seed dispersal. These plants include many keystone species for which small mammals are key primary and secondary dispersal agents as well as seed predators. To predict the regeneration and movement of such plant species, we must understand small mammal seed finding effectiveness, or how many seeds they find and how quickly they find them. The ability of small mammals to find seeds is a critical first step of the seed dispersal or predation process, upon which all other steps depend, but it has received relatively little attention. With a field experiment, we aimed to fill this gap, uncovering environmental, demographic, and intraspecific predictors of seed finding effectiveness. We assayed the behavior of 1296 southern red-backed voles (Myodes gapperi) and 1053 deer mice (Peromyscus maniculatus) to identify and mark individuals with different personalities. Afterward, we established experimental seed stations with white pine (Pinus strobus) seeds and red oak (Quercus rubra) acorns scattered on the forest floor. We recorded the foraging behavior of 23 voles and 18 mice with known personality and assessed the effects of seed availability, environmental factors, small mammal density, and personality on their proportion of found seeds, seed finding rates, and probability of dispersing found seeds. More timid and docile voles found fewer white pine seeds and found them slower. Voles found more red oak acorns and found them more quickly when small mammal density was higher, and individual seed finding rates increased with white pine seed availability. At the community level, forest treatment and small mammal species richness influenced the number of found and removed seeds. These results contribute to identifying the factors that influence seed finding effectiveness, enhancing our understanding of this pivotal first step of seed predation and dispersal. We highlight the effect of personality on the quantity of found seeds and underscore the importance of considering behavioral diversity when predicting seed dispersal and predation rates.

The dynamics of spatially structured populations (SSPs) depend on dispersal movements between habitat patches. Individual-level studies show that dispersal can be informed by social cues about habitat quality, such as breeding success or the number of conspecifics in a patch. However, informed dispersal has rarely been considered in studies investigating SSP dynamics. In particular, little is known about how patch dynamics are influenced by characteristics of neighboring patches, and the spatial scale of this influence. Here, we used occupancy and growth rate models to investigate the effect of breeding success and numbers in all patches of an SSP of black-headed gulls (Chroicocephalus ridibundus) on patch colonization, persistence and growth rates. The spatial scale of influence of neighboring patches was estimated using a distance decay function weighting the effect of patch covariates. Our results showed a strong influence of breeding success and breeding numbers, both in the focal patch and in neighboring patches, on patch dynamics. Persistence was higher for patches occupied by large and successful colonies, suggesting high attractiveness of such colonies, although their growth rate was reduced, probably due to increased costs of group-living. Patch colonization rates were higher within a few kilometers from patches occupied by large and successful colonies, in accordance with an attraction of dispersers to areas showing favorable breeding conditions. The breeding success of neighboring patches from the entire SSP reduced patch persistence, but only for patches that failed to produce chicks, and negatively affected the growth rate of persisting colonies, consistent with individuals moving away towards higher quality habitats. These results advocate for the use of social information in black-headed gull dispersal decisions. However, we were unable to distinguish between the use of breeding success (public information) and breeding numbers (conspecific attraction), which were highly correlated. Our findings emphasize the need to consider neighboring patches as dynamic components of the landscape that actively shape dispersal decisions, with consequences on SSP dynamics.

Understanding how parasites spread is crucial for preventing infections and predicting epidemic dynamics. These efforts are challenging for environment-borne parasites because transmission is host density-independent. We monitored the dynamics of Pasteuria ramosa, a common bacterial parasite of Daphnia magna with prolonged free-living transmission stages (spores). Spores are released into the sediment from decaying host cadavers. Transmission is believed to happen from sediment to host, though recent work has challenged this assumption, suggesting that transmission may also happen in the water column. We collected water samples during an epidemic and found infectious spore levels in the water, thus confirming this transmission pathway. Water column infectivity correlated with epidemic dynamics, suggesting that this pathway contributes to disease dynamics. We demonstrated experimentally that spores have a low sedimentation rate, suggesting that once suspended in the water, they remain in suspension for extended periods. We excluded that spores are released in the free water through macroinvertebrate predation or decomposition of sinking dead Daphnia, thus suggesting that perturbation transfers spores from the sediment to the water, potentially by water birds and large zooplankton. This research contributes insights into the transmission of environment-borne parasites, emphasizing the importance of considering the physical environment and ecological community.