How plasticity, genetic assimilation and cryptic genetic variation may contribute to adaptive radiationsreview
Аннотация: There is increasing evidence that phenotypic plasticity can promote population divergence by facilitating phenotypic diversification and, eventually, genetic divergence. When a 'plastic' population colonizes a new habitat, it has the possibility to occupy multiple niches by expressing several distinct phenotypes. These initially reflect the population's plastic range but may later become genetically fixed by selection via the process of 'genetic assimilation' (GA). Through this process multiple specialized sister lineages can arise that share a common plastic ancestor - the 'flexible stem'. Here, we review possible molecular mechanisms through which natural selection could fix an initially plastic trait during GA. These mechanisms could also explain how GA may contribute to cryptic genetic variation that can subsequently be coopted into other phenotypes or traits, but also lead to nonadaptive responses. We outline the predicted patterns of genetic and transcriptional divergence accompanying flexible stem radiations. The analysis of such patterns of (retained) adaptive and nonadaptive plastic responses within and across radiating lineages can inform on the state of ongoing GA. We conclude that, depending on the stability of the environment, the molecular architecture underlying plastic traits can facilitate diversification, followed by fixation and consolidation of an adaptive phenotype and degeneration of nonadaptive ones. Additionally, the process of GA may increase the cryptic genetic variation of populations, which on one hand may serve as substrate for evolution, but on another may be responsible for nonadaptive responses that consolidate local allopatry and thus reproductive isolation.
Год издания: 2016
Авторы: Ralf Schneider, Axel Meyer
Издательство: Wiley
Источник: Molecular Ecology
Ключевые слова: Genetic diversity and population structure, Species Distribution and Climate Change, Animal Ecology and Behavior Studies
Другие ссылки: Molecular Ecology (HTML)
KOPS (University of Konstanz) (PDF)
KOPS (University of Konstanz) (HTML)
PubMed (HTML)
KOPS (University of Konstanz) (PDF)
KOPS (University of Konstanz) (HTML)
PubMed (HTML)
Открытый доступ: green
Том: 26
Выпуск: 1
Страницы: 330–350