Hi all

According to many papers I have read on detection of AHB (mainly American in
origin) and in particular ABJ Dec 1991 p782 & p783.

The majority of colonies considered to be AHB produced 4.9 mm cells and
2.05% of such colonies produced 5.0 mm cells and that if  4.9 mm cells and
5.0 mm cells were considered as "Africanised" the number of false positives
would be low.

I take this to mean that there is a demarcation between AHB & EHB at about
5.0 mm and there may be a slight overlap.

Most of this work was done 1987-89

Barry Sergeant informs us...
> today our "natural" wild scutellata swarms construct cells between 4.3
> and 4.7mm - of own choice.

From the above we can infer that either, AHB and scutellata are not the same
thing, or if we accept that scutellata is AHB then something else must have
caused the shift in cellsize in the Americas.

As we only see bees larger than 5.1 cellsize in the "developed world" where
foundation has been used for a century or so, is it not possible that the
whole population of bees, that the morphometric studies were conducted on,
were larger because all managed bees on foundation exibit an enlargement?

There are some that do not accept that foundation sizes have increased over
the last century. Fine I have no "time machine" to go back and collect the
evidence but... If this enlargement has not occured why then have queen
excluder grid spacings increased from 4.2 mm up to 4.9 mm over that period?
and why has the bee space dimension gradually increased from 6 mm to 9 mm?
(part of the answer to the last question lies in timber seasoning but there
has been an increase in bee space allowance over the last 150 years.)

The largest bee that occurs in the "wild" appears to be the high altitude
variant of "Montecola" with a cellsize of  5.0 - 5.1 mm. I do not think it
unreasonable to suggest that a low altitude upper limit of 5.00 mm for the
developed world, would have existed prior to 1850 as this would fit the
relationship with Barry's present day scuts.

None of the above amounts to "proof" but they all seem to point in the same
direction.
I am quite prepared to be wrong, but at the moment I chose to adopt the
stance that foundation enlargement has occurred.  I do not know what the
results will be when I have regressed my bees to a cellsize that that I
consider would have been "natural" 120 years ago.

The question so often raised... what happens to swarms and combs that are
raised from plain wax starters? I answer this with another question, If the
bees are already enlarged why would they not continue to build enlarged
comb? I however if they are "kickstarted" by small celled starter strips
then only after a few generations they will return to a smaller size, albeit
with a few "ugly" transitions, even though the enlargement took place over
thousands of generations in small incremental steps.

We are using the term "regression" which has overtones of the bees being
forced to do something unnatural. I consider that the regression is merely
returning things to the "status quo" of 120 years ago.

Regards From:- Dave Cushman, G8MZY
Beekeeping and Bee Breeding, http://website.lineone.net/~dave.cushman
IBList Archives, http://website.lineone.net/~d.cushman