Format

Send to

Choose Destination
See comment in PubMed Commons below
Proc Biol Sci. 2000 Jul 22;267(1451):1399-405.

History or current selection? A molecular analysis of 'area effects' in the land snail Cepaea nemoralis.

Author information

  • 1Institute of Genetics, Queens Medical Centre, University of Nottingham, UK. a.davison@hgmp.mrc.ac.uk

Abstract

We have used molecular variation in microsatellite and mitochondrial DNA to throw light on the origins of enigmatic geographical patterns, known as 'area effects', in the shell polymorphisms of the land snail Cepaea nemoralis. Our aim was to assess the relative importance of recent selection and historical events in the formation of these patterns. On the Marlborough Downs in Wiltshire, England, the 'type locality' for area effects, the frequencies of microsatellites are significantly associated with the frequencies of alleles for shell banding. A less clear association is found between microsatellites and shell colour. Mitochondrial haplotypes show no significant relationships. Although the correlated geographical patterns could be the results of random genetic drift from an initially uniform array of populations, the magnitudes of the patterns, and of the correlations between them, seem too strong to have arisen by drift since the last glaciation. Our results suggest that invasions from refugia have been the most important factors in forming area effects.

PMID:
10983823
PMCID:
PMC1690693
DOI:
10.1098/rspb.2000.1156
[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center