In:
Molecular Ecology, Wiley, Vol. 24, No. 11 ( 2015-06), p. 2759-2776
Abstract:
Host race formation, the establishment of new populations using novel resources, is a major hypothesized mechanism of ecological speciation, especially in plant‐feeding insects. The initial stages of host race formation will often involve phenotypic plasticity on the novel resource, with subsequent genetically based adaptations enhancing host‐associated fitness differences. Several studies have explored the physiology of the plastic responses of insects to novel host environments. However, the mechanisms underlying evolved differences among host races and species remain poorly understood. Here, we demonstrate a reciprocal larval performance difference between two closely related species of R hagoletis flies, R . pomonella and R . zephyria , specialized for feeding in apple and snowberry fruit, respectively. Microarray analysis of fly larvae feeding in apples versus snowberries revealed patterns of transcriptome‐wide differential gene expression consistent with both plastic and evolved responses to the different fruit resources, most notably for detoxification‐related genes such as cytochrome p450s. Transcripts exhibiting evolved expression differences between species tended to also demonstrate plastic responses to fruit environment. The observed pattern suggests that R hagoletis larvae exhibit extensive plasticity in gene expression in response to novel fruit that may potentiate shifts to new hosts. Subsequent selection, particularly selection to suppress initially costly plastic responses, could account for the evolved expression differences observed between R . pomonella and R . zephyria , creating specialized races and new fly species. Thus, genetically based ecological adaptations generating new biodiversity may often evolve from initial plastic responses in gene expression to the challenges posed by novel environments.
Type of Medium:
Online Resource
ISSN:
0962-1083
,
1365-294X
DOI:
10.1111/mec.2015.24.issue-11
Language:
English
Publisher:
Wiley
Publication Date:
2015
detail.hit.zdb_id:
2020749-9
detail.hit.zdb_id:
1126687-9
SSG:
12
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