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Phenotypic plasticity and adaptive evolution enable population persistence in response to global change. However, there are few experiments that test how these processes interact within and across generations, especially in marine species with broad distributions experiencing spatially and temporally variable temperature and p CO 2 . We employed a quantitative genetics experiment with the purple sea urchin, Strongylocentrotus purpuratus , to decompose family-level variation in transgenerational and developmental plastic responses to ecologically relevant temperature and p CO 2 . Adults were conditioned to controlled non-upwelling (high temperature, low p CO 2 ) or upwelling (low temperature, high p CO 2 ) conditions. Embryos were reared in either the same conditions as their parents or the crossed environment, and morphological aspects of larval body size were quantified. We find evidence of family-level phenotypic plasticity in response to different developmental environments. Among developmental environments, there was substantial additive genetic variance for one body size metric when larvae developed under upwelling conditions, although this differed based on parental environment. Furthermore, cross-environment correlations indicate significant variance for genotype-by-environment interactive effects. Therefore, genetic variation for plasticity is evident in early stages of S. purpuratus , emphasizing the importance of adaptive evolution and phenotypic plasticity in organismal responses to global change.
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Comparison of thermal developmental plasticity among seven recently sympatric Anolis species: insights into the evolution of reaction norms
Abstract Theory predicts that thermal developmental plasticity evolves in response to thermal heterogeneity, suggesting that plasticity may be an important trait for establishment in novel climates. However, few studies use multispecies comparisons to examine how plasticity evolves, meaning that there is little empirical basis with which to examine key theoretical predictions. We estimate patterns of thermal developmental plasticity in morphological and performance traits for 7 Anolis lizard species inhabiting South Florida, USA. We found interspecific differences as well as intraspecific variation in reaction norms across species. Neither temperature heterogeneity in present-day invasive ranges in Florida nor historical temperature heterogeneity from the contemporary native ranges predicted reaction norm variation. Phylogeny and species identity typically predicted around 90%–95% of reaction norm variation. Overall, these results suggest that thermal developmental plasticity in these traits exhibits variation that could be inconsistent with patterns expected under adaptive evolution to macroclimate. Examining the role of maternal nesting behavior and sampling of additional species can help to distinguish between neutral variation and selection toward multiple adaptive peaks. Our comparative study of thermal developmental plasticity in lizards provides new insights about macroevolutionary dynamics behind the evolution of developmental plasticity and the conditions under which adaptive plasticity is expected to evolve.
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- Award ID(s):
- 1942145
- PAR ID:
- 10641004
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Evolution
- Volume:
- 79
- Issue:
- 9
- ISSN:
- 0014-3820
- Format(s):
- Medium: X Size: p. 1756-1772
- Size(s):
- p. 1756-1772
- Sponsoring Org:
- National Science Foundation
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