Fitness and microsatellite diversity estimates were not correlated in two outbred anuran populations.

Larval fitness traits were investigated in two anuran species (Bufo calamita and Rana temporaria) under controlled laboratory conditions, and allelic diversity measured in the same individuals at five and seven microsatellite loci, respectively. For both species there were significant differences among sibships in larval growth and development rates, and in some cases also in microsatellite heterozygosity and mean d2 (a measure of diversity based on differences in allele sizes). However, there were no significant correlations between any of the fitness and genetic measures either among all individuals, among sibships or among individuals within sibships. Under the conditions and within the statistical power of the study there was no relationship between fitness-related quantitative trait variation and that seen at presumed-neutral microsatellite loci in these outbred populations.