POLYMORPHIC SEX-SPECIFIC SEQUENCES IN BIRDS OF PREY

A red kite (Milvus milvus) clone, which cross-hybridizes to a human mi nisatellite, reveals complex polymorphic patterns in members of the Ac cipitridae, a family of 217 species of birds of prey, which includes t he kites, hawks and eagles. The total absence of hybridization to male s implies that the sequence is located on the W chromosome, and stable inheritance from mother to daughter suggests that the patterns evolve as haploid matrilines. This has allowed not only the development of a simple and rapid sexing technique but may also provide a means of mon itoring matriarchal success and dispersion. As an example, a survey of 36 continental European red kite nests revealed 24 different haplotyp es, whereas only 2 were found among 53 Welsh nests. The results show t he effect of a dramatic bottleneck in Wales and may provide evidence o f recent introgression from the continent.