Honey bee colonies in hives live in both darkness inside
their hives and in light when they are out foraging.
If two colonies are opened in sunlight and some frames are
removed from each to spare boxes. And if then the exposed combs are
spread apart so that they are roughly twice as far apart as they would
be normally. Then after a period of about ten minutes the frames from
the two colonies can be mixed without fighting.
The above is a simple observation the actual reasons are not
understood, but this does not stop us making use of the phenomena.
The honey bees visible spectrum starts a little higher than
human eyesight at about 422 nanometres and extends to 646 nanometres
at the red end (Bertholf 1931) these are extremes that are themselves
variable... 422 nm - 483 nm and 504 nm - 646 nm respectively. Normal
human response is 400 nm to 770 nm (there are also 'spreads' to these
figures). Von Frish however, states 313 nm as the lower limit and
speculates that this is perceived in a chromatic fashion rather than
as flourescence.
The green curve represents human spectral response, whilst
the overlaid red curve is that of the honey bee. There has been some
conjecture that the bee's response either stays at roughly 10% or
increases again to a secondary peak as the wavelength decreases into
the ultra violet. Such conjecture mainly stems from the ray patterns
in flowers that become enhanced (to human vision) when illuminated by
UV.
Much of this work will be revisited using direct
measurements of nerve impulses using electrodes implanted in bee's
brains. The work is under way, but is considered too incomplete for
publication... When confidence can be placed in the results I will
publish a page on this website.
The effectiveness of each part of the spectrum. In 1917 many
experiments were performed by S.O. Mast, whereby bees reactions to
coloured light were compared to their reactions to white light (white
as judged by human eyes).
Individual colours can be distinguished by humans, Von
Frish and Mast consider the visualisation of colour to be the same in
bees as in humans, but Bertholf attempts to consider 'brightness',
'colour' (frequency or wavelength) and 'saturation'. There are many
pitfalls in this work which up to now has relied on human observation
to establish relative 'brightness' between a 'coloured' light source
and a 'white' light source.
I personally believe that all this work needs re-appraisal
due to a revision in the theory of colour vision that occurred
around 1980.
