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Many anuran amphibians (frogs and toads) rely on aquatic habitats during their larval stage. The quality of this environment can significantly impact lifetime fitness and population dynamics. Over 450 studies have been published on environmental impacts on anuran developmental plasticity, yet we lack a synthesis of these effects across different environments. We conducted a meta-analysis and used a comparative approach to understand whether developmental plasticity in response to different larval environments produces predictable changes in metamorphic phenotypes. We analyzed data from 124 studies spanning 80 anuran species and six larval environments and showed that intraspecific variation in mass at metamorphosis and the duration of the larval period is partly explained by the type of environment experienced during the larval period. Changes in larval environments tended to reduce mass at metamorphosis relative to control conditions, with the degree of change depending on the identity and severity of environmental change. Higher temperatures and lower water levels shortened the duration of the larval period, whereas less food and higher densities increased the duration of the larval period. Phylogenetic relationships among species were not associated with interspecific variation in mass at metamorphosis plasticity or duration of the larval period plasticity. Our results provide a foundation for future studies on developmental plasticity, especially in response to global changes. This study provides motivation for additional work that links developmental plasticity with fitness consequences within and across life stages, as well as how the outcomes described here are altered in compounding environments.
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Form–function relationships within species are uncoupled from those across species in swimming and jumping performance in arboreal frogs
Abstract Variation of form–function relationships within populations is the substrate for adaptation at higher levels. Therefore, assessing similarity in form–function relationships within and between species may help reveal the processes shaping functional diversity. Here, we test such similarity across three levels of anuran phenotypic divergence: within a population, among species in a single family (Hylidae; ~60 myr), and across a much broader sample of all anuran species using a single microhabitat (arboreal; ~120 myr). We expected less interspecific divergence to show higher similarity of form–function relationships with the intraspecific level. We analyzed the relationships between locomotor performance (in both swimming and jumping) and several hindlimb traits across these three evolutionary levels. While we found a positive correlation between swimming and jumping velocity at both intra- and interspecific levels, relationships between performance and body form did not match across levels. We suggest that different strengths of functional constraints or trade-offs may have produced more variation in form–function relationships across species, decoupling them from within-species patterns. We conclude that performance landscapes are likely qualitatively different across the different evolutionary scales, potentially reflecting changes in the relative importance of different behaviors across all arboreal species.
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- Award ID(s):
- 2430681
- PAR ID:
- 10621511
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Evolution
- Volume:
- 79
- Issue:
- 7
- ISSN:
- 0014-3820
- Format(s):
- Medium: X Size: p. 1227-1242
- Size(s):
- p. 1227-1242
- Sponsoring Org:
- National Science Foundation
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