Oysters, like many other marine species, are characterized by very high fertilities. Natural or hatchery populations, often present very low Ne/N ratios (Hedgecock, 1994). It can be explained by very high variances of their breeding success (Li and Hedgecock, 1998), the effective population size being estimated through the temporal variance of the allelic frequencies in natural populations (Hedgecock et al., 1992) or, more directly, through the estimated number of founders in hatchery populations (Launey, 1998). This document is a presentation of the results of a number of experiments, realised in the scope of the European program "GENEPHYS" (FAIR 95-421), and using microsatellite markers to analyse the parental contributions in the flat oyster Crassostrea... |