MAXIMUM-LIKELIHOOD-ESTIMATES OF GENE-FREQUENCIES AND RACIAL ADMIXTURE IN APIS-MELLIFERA L (AFRICANIZED HONEYBEES)

In order to obtain estimates of gene frequencies and other genetic parameters in Apis mellifera, samples are usually obtained from groups of haploid male (drones) and sterile female (workers) offspring, each group being descended from a multiply-mated single queen. A probabilistic model of segregation is presented which allows for maximum-likelihood estimates of genetic parameters in the reproductive individuals using the genotypic segregations of workers and drones from different colonies. Marginal probabilities of these segregations are calculated for each queen genotype by assuming a Dirichlet distribution for the fertilization frequencies of the different male alleles stored in the spermathecae. Estimates of gene frequencies and racial proportions in Africanized honey bees from different localities in Brazil and Central America reveal geographical heterogeneity in these parameters, possibly as a result of different levels of gene flow from European races.