Phylogeography of competing sexual and parthenogenetic forms of a freshwater flatworm: patterns and explanations.

ABSTRACT:

Background

Models of the maintenance of sex predict that one reproductive strategy, sexual or parthenogenetic, should outcompete the other. Distribution patterns may reflect the outcome of this competition as well as the effect of chance and historical events. We review the distribution data of sexual and parthenogenetic biotypes of the planarian Schmidtea polychroa.

Results

S. polychroa lives in allopatry or sympatry across Europe except for Central and North-Western Europe, where sexual individuals have never been reported. A phylogenetic relationship between 36 populations based on a 385 bp fragment of the mitochondrial cytochrome oxidase I gene revealed that haplotypes were often similar over large geographic distances. In North Italian lakes, however, diversity was extr

SUBMITTER: Pongratz N 

PROVIDER: S-EPMC280671 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature