Temporal changes in mitochondrial diversity highlights contrasting population events in Macaronesian honey bees

Abstract

Temporal studies of the genetic diversity are important as they enable detection of genetic changes that can constitute threats to the honey bee populations. In this study, we analyzed the present mitochondrial diversity in honey bee populations inhabiting the Macaronesian archipelagos (Azores, Madeira and Canary), and compared with previous data over a 10-year period. Present populations showed mainly haplotypes characteristic of the evolutionary African sub-lineage (AIII), but foreign mitochondrial haplotypes (M7, C1 and C2) were also observed suggesting honey bee queens introductions with different origins. Differential patterns of change in mitochondrial diversity and introgression were detected: whereas a low decrease was detected on Madeira and São Miguel, major changes were observed on El Hierro, La Palma and La Gomera. Despite loss of AIII haplotypes relative to previous data, extant frequency and distribution of the African sub-lineage in the Macaronesian archipelagos appears sufficiently large to propose potential conservation policies for protecting local ecotypes.