Sharing is living: The role of habitat heterogeneity in the coexistence of closely related species

• Published in: Ecology and evolution 2023-03, Vol.13 (3), p.e9930-n/a
• Main Authors: Sanches, Fábio H. C., De Grande, Fernando R., Costa, Tânia M., Barreto, Rodrigo E.
• Format: Article
• Language: English
• Subjects: Animal reproduction; behavioral ecology; Biodiversity Ecology; Coexistence; Crustaceans; Ecophysiology; Ecosystem Ecology; Ecosystems; Estuaries; Estuarine ecosystems; Evolutionary Ecology; Experiments; fiddler crab; Foraging behavior; habitat partition; Habitats; heat stress; Heterogeneity; Intertidal zone; Light; Mangroves; Microenvironments; Microhabitats; Mud flats; Ocypodidae; Physiological effects; Physiology; Population Ecology; Sediments; Shading; spatial distribution; Species; sunlight shading; Temperature effects; Temperature tolerance; Thermal stress; thermoregulation; Vegetation
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.9930

In biologically diverse ecosystems, an essential process to support competing species to coexist is ecological differentiation. Habitat heterogeneity is, hence, important in establishing species abundance and richness, favoring the coexistence of species due to habitat partition. In this context, shading and species thermal tolerance can be good factors to elucidate the role of habitat heterogeneity in the habitat partition among closely related species. Herein, we study shading effects in microhabitat selection, behavior, and physiological limitation on two species of fiddler crabs (Leptuca leptodactyla and Leptuca uruguayensis). Indeed, shading conditions influenced fiddler crabs species proportion over time, with L. leptodactyla more associated with nonshaded/warmer areas while the L. uruguayensis to shaded/cooler ones. They also adjusted their behavior differently from each other to deal with thermal stress. Finally, we have demonstrated that these effects are related to species' physiological limitations. We conclude that biologically diverse ecosystems, such as intertidal regions from estuaries (e.g., mudflats and mangroves), support the coexistence between closely related species by reducing competition due to habitat partition. Our findings provide knowledge of the mechanisms behind the coexistence between estuarine sympatric species. We demonstrated that it is favored by the relationship between the diversification of microhabitats, such as shading degree, and by species’ intrinsic factors, such as thermal stress tolerance. Thus, habitat heterogeneity might favor species diversity in a general manner, due to reduced costs associated with habitat partition.