GENETIC DIFFERENCES BETWEEN EARLY-AND-LATE-BREEDING EURASIAN KESTRELS

Question: Is there a genetic difference between early-breeding kestrels (Falco tinnunculus), which typically lay five or six eggs, and late-breeding kestrels, which, although sympatric, usually lay only four eggs? Field site: Cultivated and set-aside fields of a Mediterranean area of 1200 km2, near Rome, Italy. Methods: We compared the genotypes of chicks belonging to the two groups by analysing the difference at five microsatellite loci. Conclusions: Early- and late-hatched chicks are genetically dissimilar, with an average FST-value of 0.058. This result suggests assortative mating-by-time and the possibility of adaptive divergence between early and late breeders within sympatric populations.