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Date: | Sat, 16 Feb 2002 11:25:42 -0500 |
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Greetings
There have been many discussions in this forum on the worker cell
size of naturally built comb. Despite the fact that many researchers
have concurred that European bees make comb with worker cells that
average around 53 mm (Taber & Owens, Michener), some people contend
that this size reflects an artificial enlargement *caused* by the use
of foundation based on larger than natural dimensions. This idea
itself is based on a faulty understanding of biology (externally
induced characteristics are not passed on to offspring).
Nevertheless, I have some information that I think can clarify the
discussion.
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Beekeeping with European hives has been carried out in Central
America since at least 1830. Early beekeepers used logs and simple
box hives. As late as 1979, this type of hive was still the main type
in use in most of Central America. Movable frame hives were present
in the following numbers in these countries:
El Salvador 44%
Costa Rica 15%
Guatemala 3-25%
Belize a few
Panama none
(from Crane, 1990, 1999)
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Marla Spivak spent much time in Costa Rica observing the onset of
Africanization. She measured the cell size of the European bees
before, during and after the arrival. She refers data collected by
researchers as early as 1973 indicating European bees in the tropics
built cells ranging from 5.0 to 5.4 mm. These bees, being kept in box
hives for centuries, can hardly said to be affected by manufactured
comb foundation.
Africanized bee cells were found to be in the range of 4.6 to 5.0 mm,
throughout South America. (In Africa, scutellata ranges from 4.7 to
4.9.) According to Spivak, European bees in Costa Rica in 1984 built
comb with cells measuring 5.3 mm. When African bees entered the area
the numbers immediately fell to 5.0 mm. Later, the range for African
bees was shown to be 4.7 to 5.1.
She emphasizes that while cell size is a clear indication of
Africanization, these bees do not necessarily exhibit the fierce
behavior normally associated with this bee type. Even bees with cells
as small as 4.7 mm were not always extremely defensive.
(Spivak, 1991)
--
Peter Borst <[log in to unmask]>
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