Drs. Gloria DeGrandi-Hoffman of the ARS Carl Hayden Bee Research Center,
Tucson, Ariz., and Stanley S. Schneider of the University of North Carolina
at Charlotte showed that African honey bees exhibit a greater degree of
thelytokous parthenogenesis than do European honey bees.
In general, there are two kinds of parthenogenesis, the development of an
individual from an unfertilized egg, found in insects. The most common for
honey bees is "arrhenotokous parthenogenesis", where females arise from
fertilized eggs and males from those that are not fertilized. This is the
case for the majority of races or subspecies (ecotypes) of Apis mellifera.
Mr. Flottum suggested that experience shows that Africanized honey bees in
the Americas are notoriously difficult to requeen. A reason for this,
according to the study, is that very quickly (within a week) after the queen
is removed, Africanized worker bees are capable of activating their ovaries
to produce viable female eggs. European worker bees' ovaries, on the other
hand, don’t start producing eggs until the queen has been missing for at
least three weeks. And these eggs typically produce male offspring.
The Africanized workers' faster, one-week response to queenlessness,
however, combined with the ability to produce females, works against what
most beekeepers know about requeening European honey bee colonies.
from APIS Volume 18, Number 6, June 2000
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