Although African bees in the Americas can be distinguished genetically
from African bees in Africa, the difference is very small and could be
due to genetic drift, rather than hybridization. The difference
between both African types and the European bees present in the
Americas is far greater. The evidence indicates that African and
American bees do NOT produce hybrids, but rather, the Africans replace
the American bees wherever they occur. As cited below, even the
introduction of 23000 Italian queens did nothing to alter the African
bee in Brazil.
* * *
throughout much of its range in the New World, the invading
honey bee population has remained essentially African in its nesting
biology,
swarming and absconding behavior, foraging and
diet selection, and mitochondrial DNA (mtDNA) characteristics
the hybrid-swarm concept was seriously challenged
when mtDNA polymorphisms revealed that over 97% of feral colonies from
Brazil,
Venezuela, Honduras, and Mexico possessed African mtDNAhaplotypes;
east European
mitotypes were virtually absent. Because honey bee mtDNA is maternally
inherited without recombination, this indicated that feral African
colonies were
matrilineal descendants of African bees, most likely A. m. scutellata
Thus, even in areas where hybridization and introgression of European
genes
have been particularly likely, European mitotypes have dropped to low
frequencies,
especially in the feral population.
Although the African bees in the Neotropics are no longer genetically
identical to the honey bees of southern Africa, they have largely
retained the
genome of A. m. scutellata despite almost 50 years of contact with
European bees.
Genetic structure of honeybee populations from southern Brazil and
Uruguay
Nilza Maria Diniz, et al
Genetics and Molecular Biology, 26, 1, 47-52 (2003)
* * *
Although traditional morphometrics is the basis of the current
identification of all Apis mellifera subspecies, the new methods of
automated measures and geometric morphometry had been used to
distinguish or to characterize these groups in just a few recent works
(Francoy et al., 2006a, 2008; Tofilski, 2008). The high correct
classification rates that we found indicate that forewings carry
sufficient information to distinguish the bee groups that we examined.
Along with molecular analysis of mtDNA origin, the association of
these methodologies was found to be very informative. We used these
analyses together to examine whether a population of Africanized honey
bees sampled the African bees first escaped in Brazil had changed
after 35 years.
The absence of European-derived mtDNA in the current population,
indicating complete substitution of the European queens in the
population would also help to explain the greater proximity of the
Africanized bees to the A. m. scutellata group. Even with the
distribution of more than 23,000 A. m. ligustica queens to the
beekeepers at the beginning of the Africanization process (Gonçalves,
1974) there was apparently no impact on the established population in
2002. This substitution of mitotypes seems to be very common in the
regions occupied by Africanized bees.
Morphometric and genetic changes in a population of Apis mellifera
after 34 years of Africanization
T.M. Francoy, et al
Genetics and Molecular Research 8 (2): 709-717 (2009)
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