The Past Contribution and Future Fate of Genetic Variants under Climate Change in an Island Population of Musa itinerans
Journal
The American naturalist
Journal Volume
202
Journal Issue
4
Pages
558-570
Date Issued
2023-10
Author(s)
Abstract
AbstractGenetic variation within species is crucial for sessile species to adapt to novel environments when facing dramatic climate changes. However, the debate continues whether standing ancestral variation adaptive to current environmental variability is sufficient to guarantee future suitability. Using wild banana Musa itinerans, we investigated the relative contribution of standing ancestral variation versus new mutations to environmental adaptation and inferred their future fate. On the continental island of Taiwan, local populations immigrated from the Southeast Asian continent during the ice age and have been isolated since then. This allows the classification of genetic variants into standing ancestral variation (polymorphic in Taiwan and the continent) and new mutations (polymorphic only in Taiwan). For temperature-related variables where Taiwan is mainly within the ancestral climatic range, standing ancestral variation had a slightly stronger association than new mutations. New mutations were more important for precipitation-related variables, where northeastern Taiwan had much more winter rainfall than most of continental Southeast Asia. Upon future climate change, new mutations showed higher genetic offset in regions of abrupt transition between allele frequency and local environments, suggesting their greater spatial heterogeneity of future vulnerability.
Subjects
climate change; genetic variation; local adaptation; new mutation; standing ancestral variation
SDGs
Publisher
University of Chicago Press
Type
journal article