Parallelism and historical contingency during rapid ecotype divergence in an isopod
Författare
Summary, in English
Recent studies on parallel evolution have focused on the relative role of selection and historical contingency during adaptive divergence. Here, we study geographically separate and genetically independent lake populations of a freshwater isopod (Asellus aquaticus) in southern Sweden. In two of these lakes, a novel habitat was rapidly colonized by isopods from a source habitat. Rapid phenotypic changes in pigmentation, size and sexual behaviour have occurred, presumably in response to different predatory regimes. We partitioned the phenotypic variation arising from habitat ('selection': 81-94%), lake ('history': 0.1-6%) and lake × habitat interaction ('unique diversification': 0.4-13%) for several traits. There was a limited role for historical contingency but a strong signature of selection. We also found higher phenotypic variation in the source populations. Phenotype sorting during colonization and strong divergent selection might have contributed to these rapid changes. Consequently, phenotypic divergence was only weakly influenced by historical contingency.
Avdelning/ar
Publiceringsår
2009
Språk
Engelska
Sidor
1098-1110
Publikation/Tidskrift/Serie
Journal of evolutionary biology
Volym
22
Issue
5
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
John Wiley & Sons Inc.
Ämne
- Biological Sciences
Nyckelord
- Adaptive radiation
- Historical contingency
- Mating propensity
- Parallel evolution
- Phenotype sorting
- Pigmentation
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1420-9101