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Abstract The equilibrium theory of island biogeography and its quantitative consideration of origination and extinction dynamics as they relate to island area and distance from source populations have evolved over time and enriched theory related to many disciplines in spatial ecology. Indeed, the island focus was catalytic to the emergence of landscape ecology and macroecology in the late 20th century. We integrate concepts and perspectives of island biogeography, landscape ecology, macroecology, and metacommunity ecology, and show how these disciplines have advanced the understanding of variation in abundance, biodiversity, and composition of bat communities. We leverage the well‐studied bat fauna of the islands in the Caribbean to illustrate the complex interplay of ecological, biogeographical, and evolutionary processes in molding local biodiversity and system‐wide structure. Thereafter, we highlight the role of habitat loss and fragmentation, which is increasing at an accelerating rate during the Anthropocene, on the structure of local bat communities and regional metacommunities across landscapes. Bat species richness increases with the amount of available habitat, often forming nested subsets along gradients of patch or island area. Similarly, the distance to and identity of sources of colonization influence the richness, composition, and metacommunity structure of islands and landscape networks.
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Multispecies coexistence in fragmented landscapes
Spatial dynamics have long been recognized as an important driver of biodiversity. However, our understanding of species’ coexistence under realistic landscape configurations has been limited by lack of adequate analytical tools. To fill this gap, we develop a spatially explicit metacommunity model of multiple competing species and derive analytical criteria for their coexistence in fragmented heterogeneous landscapes. Specifically, we propose measures of niche and fitness differences for metacommunities, which clarify how spatial dynamics and habitat configuration interact with local competition to determine coexistence of species. We parameterize our model with a Bayesian approach using a 36-y time-series dataset of three Daphnia species in a rockpool metacommunity covering >500 patches. Our results illustrate the emergence of interspecific variation in extinction and recolonization processes, including their dependencies on habitat size and environmental temperature. We find that such interspecific variation contributes to the coexistence of Daphnia species by reducing fitness differences and increasing niche differences. Additionally, our parameterized model allows separating the effects of habitat destruction and temperature change on species extinction. By integrating coexistence theory and metacommunity theory, our study provides platforms to increase our understanding of species’ coexistence in fragmented heterogeneous landscapes and the response of biodiversity to environmental changes.
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- Award ID(s):
- 2024349
- PAR ID:
- 10356189
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 119
- Issue:
- 37
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1073/pnas.2201503119
