Molecular characterization and population structure of the honeybees from the balearic islands (Spain)

Honeybees (Apis mellifera L.) were collected from 23 localities on the Balearic islands in the Mediterranean Sea. The mitochondrial genome (mtDNA) was surveyed for diagnostic restriction sites and characterized with DraI digestion of the tRNA$^{{\rm leu}}$-COII intergenic region. Both approaches demonstrated that honeybees bearing either African or west European haplotypes coexist on the Balearic islands. Two African and two west European haplotypes were found with different frequencies and distribution among the islands. Phylogenetic and population structure analyses support the clustering of these islands in two groups: Majorca-Minorca (Gymnesic) and Ibiza-Formentera (Pityusic) what corroborates the current biogeographical division of the Balearic organisms. These results partially agree with the observed distribution of African haplotypes in honeybee populations from other Mediterranean islands. The present distribution of genetic markers may reflect also the influence of human movements, trade and settlements from prehistoric times