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Title: Africanization of a feral honey bee ( Apis mellifera ) population in S outh T exas: does a decade make a difference?

The arrival to theUnitedStates of theAfricanized honey bee, a hybrid betweenEuropean subspecies and theAfrican subspeciesApis mellifera scutellata, is a remarkable model for the study of biological invasions. This immigration has created an opportunity to study the dynamics of secondary contact of honey bee subspecies fromAfrican andEuropean lineages in a feral population inSouthTexas. An 11‐year survey of this population (1991–2001) showed that mitochondrial haplotype frequencies changed drastically over time from a resident population of eastern and western European maternal ancestry, to a population dominated by theAfrican haplotype. A subsequent study of the nuclear genome showed that theAfricanization process included bidirectional gene flow between European and Africanized honey bees, giving rise to a new panmictic mixture ofA. m. scutellata‐and European‐derived genes. In this study, we examined gene flow patterns in the same population 23 years after the first hybridization event occurred. We found 28 active colonies inhabiting 92 tree cavities surveyed in a 5.14 km2area, resulting in a colony density of 5.4 colonies/km2. Of these 28 colonies, 25 were ofA. m. scutellatamaternal ancestry, and three were of western European maternal ancestry. No colonies of eastern European maternal ancestry were detected, although they were present in the earlier samples. NuclearDNArevealed little change in the introgression ofA. m. scutellata‐derived genes into the population compared to previous surveys. Our results suggest this feral population remains an admixed swarm with continued low levels of European ancestry and a greater presence of African‐derived mitochondrial genetic composition.

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Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Ecology and Evolution
Medium: X Size: p. 2158-2169
["p. 2158-2169"]
Sponsoring Org:
National Science Foundation
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