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Niche models at inter- and intraspecific levels reveal hierarchical niche differentiation in midwife toads.

ABSTRACT: Variation and population structure play key roles in the speciation process, but adaptive intraspecific genetic variation is commonly ignored when forecasting species niches. Amphibians serve as excellent models for testing how climate and local adaptations shape species distributions due to physiological and dispersal constraints and long generational times. In this study, we analysed the climatic factors driving the evolution of the genus Alytes at inter- and intraspecific levels that may limit realized niches. We tested for both differences among the five recognized species and among intraspecific clades for three of the species (Alytes obstetricans, A. cisternasii, and A. dickhilleni). We employed ecological niche models with an ordination approach to perform niche overlap analyses and test hypotheses of niche conservatism or divergence. Our results showed strong differences in the environmental variables affecting species climatic requirements. At the interspecific level, tests of equivalence and similarity revealed that sister species were non-identical in their environmental niches, although they neither were entirely dissimilar. This pattern was also consistent at the intraspecific level, with the exception of A. cisternasii, whose clades appeared to have experienced a lower degree of niche divergence than clades of the other species. In conclusion, our results support that Alytes toads, examined at both the intra- and interspecific levels, tend to occupy similar, if not identical, climatic environments.

SUBMITTER: Rodriguez-Rodriguez EJ

PROVIDER: S-EPMC7331615 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Niche models at inter- and intraspecific levels reveal hierarchical niche differentiation in midwife toads.

Rodríguez-Rodríguez Eduardo José EJ Beltrán Juan F JF Tejedo Miguel M Nicieza Alfredo G AG Llusia Diego D Márquez Rafael R Aragón Pedro P

Scientific reports 20200702 1

Variation and population structure play key roles in the speciation process, but adaptive intraspecific genetic variation is commonly ignored when forecasting species niches. Amphibians serve as excellent models for testing how climate and local adaptations shape species distributions due to physiological and dispersal constraints and long generational times. In this study, we analysed the climatic factors driving the evolution of the genus Alytes at inter- and intraspecific levels that may limi ...[more]

PMID: 32616878

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Niche models at inter- and intraspecific levels reveal hierarchical niche differentiation in midwife toads.

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Niche models at inter- and intraspecific levels reveal hierarchical niche differentiation in midwife toads.

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