Understanding what factors determine the distribution and abundance of species across a landscape is a central challenge in ecology. While much progress has been made, little attention has been paid to the history of individuals. Yet, where individuals come from and what conditions they have experienced in the past often strongly affects their current traits and performance. When interacting with other species, such carry-over effects can have the potential to alter the dynamics of populations and species interactions. However, the consequences of these effects for long-term dynamics of communities and the spatial distribution of species are largely unknown. This research project will conduct a combination of experiments using the classic model laboratory system of flour beetle, and apply computational modeling to investigate how carry-over effects influence the dynamics of communities across variable landscapes. By explicitly linking variation at the individual level to spatial variation, this research will provide novel insight into how variation at different organizational scales interacts to determine community dynamics and species coexistence in nature.
This research will contribute to society by improving our understanding in applied areas such as conservation biology and invasive species ecology. Conservation biology already recognizes that more high quality individuals improve population persistence, but how individual quality interacts in a community setting is poorly understood. Determining whether complex community interactions are important for how carry-over effects alter population dynamics could open new venues to investigation into conservation program success. Increased understanding of carry-over effects has implications for predicting the successful establishment and spread of invasive species as well, since it explores how habitat quality can combine with species interactions to promote or stop the movement of a species across a landscape. This project will provide multiple undergraduate students with research experience and career mentoring, and will support the dissertation research of a doctoral student.
This project sought to increase our understanding of how species are distributed in communities across landscapes. We specifically investigated how environmental sources of individual variation influence the structure of ecological communities which are connected by the movement of individuals between habitats. The conditions of a habitat in which individuals develop can influence their traits, such as adult behavior, morphology, or reproductive output. When individuals move to new habitats, these changes can continue to influence how individuals interact with their environment. In this study we examined how such environmental "carry-over effects" altered species interactions and community dynamics. We used a combination of computational modeling and experiments using two beetle species, which are important agricultural pests, to answer this question. In particular we investigated how carry-over affects altered community dynamics across landscapes with multiple species and patches of habitat. Our results indicate that carry-over effects can strongly influence species interactions. These changes in species interactions "scaled up" to alter community structure within a single habitat patch and how species are distributed across the landscape. For instance, carry-over effects altered which species could persist in a given environment. These results indicate that the proportion or arrangement of different habitat types across a landscape could affect the structure of ecological communities within each habitat. Besides providing novel insights into the general principles that structure natural communities, results of this study will also help to guide and improve conservation and management activities. This work demonstrates that species performance and interactions with other species can be dramatically affected by carry-over effects. Accounting for environmental carry-over effects could therefore improve conservation and management planning. This could be particularly useful in cases such as the reintroduction of endangered species into the wild and the prediction of invasive species spread and impacts across landscapes with multiple habitat types. The grant also supported and trained one graduate student and five undergraduate students from underrepresented groups in sciences.
