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Title: Evidence for ecological speciation via a host shift in the holly leaf miner, Phytomyza glabricola (Diptera: Agromyzidae)

Evolutionary radiations have been well documented in plants and insects, and natural selection may often underly these radiations. If radiations are adaptive, the diversity of species could be due to ecological speciation in these lineages. Agromyzid flies exhibit patterns of repeated host‐associated radiations. We investigated whether host‐associated population divergence and evidence of divergent selection exist in the leaf minerPhytomyza glabricolaon its sympatric host plants, the holly species,Ilex coriaceaandI. glabra. UsingAFLPs and nuclear sequence data, we found substantial genetic divergence between host‐associated populations of these flies throughout their geographic range. Genome scans using theAFLPdata identified 13 loci under divergent selection, consistent with processes of ecological speciation.EF‐1αdata suggest that I. glabrais the original host ofP. glabricolaand thatI. coriaceais the novel host, but theAFLPdata are ambiguous with regard to directionality of the host shift.

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Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Ecology and Evolution
Medium: X Size: p. 6565-6577
["p. 6565-6577"]
Sponsoring Org:
National Science Foundation
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