Molecular genetic identification of the sex of humpback whales (Megaptera novaeangliae)
Baker, C.S., R.H. Lambertson, M.T. Weinrich, J. Calambokidis, G. Early, and S.J. O'Brien. 1991. Molecular genetic identification of the sex of humpback whales (Megaptera novaeangliae). R. Hoelzel (ed.) in Genetic Ecology of Cetaceans. International Whaling Commission (special issue 13):105-111.
Hybridisation of an human Y chromosome clone (pDP 1007) with Eco RI restricted DNA from male and female humpback whales revealed restriction-fragment patterns similar to those previously reported in other placental mammals. The sex-specificity of these restriction fragments in humpback whales was verified using DNA from necropsy samples of 11 individuals from the Southern Gulf of Maine. Necropsy samples from a fin (Balaenoptera physalus), a sei (B. borealis), a gray (Eschrichtius robustus), and a bowhead whale (Balaena mysticetus) showed patterns of restriction fragments similar to those of humpback whales. Small samples of skin collected with a biopsy dart were used to determine the sex of free ranging humpback whales from the Gulf of Maine (n=17), Central California (n=20), Southeastern Alaska (n=20) and Hawaii (n=15). The sex of one additional Hawaiian humpback whale was identified from DNA extracted from sloughed skin collected from the whale's path. Regional samples were tested for biased sex ratios and the resighting histories of naturally marked individuals were examined for information concerning the function of previously described social roles or behaviour.