Most people know that honeycombs are formed of hexagonal wax cells, and that this economic arrangement stores a maximum amount of honey in a given space, since the cells are tessellated – they fit together side by side, wasting no space between them. Some people are able to restrain themselves long enough from the delectable taste of honey to notice that the intact comb consists of two layers of cells, one above the other, with a wax wall closing one layer off from the other. If they wonder how the bees were able to fill the lower layer with honey, they may deduce that in the beehive the layers are built vertically, not horizontally as in the way the comb reaches the table. Indeed the hive is full of these two-sided vertical combs with the mouths of the cells facing sideways, with just enough room between each comb for the bees to tend every cell.
Thanks to television, we are familiar enough with this sort
of thing to nod at it as just another example of nature’s ingenuity. And you
may just nod again if I tell you that the cells do not face exactly sideways,
but are tilted upwards a little so that the fresh, runny nectar is less likely
to drip out. If I now ask you to suggest what the wax wall is like that forms
the base of each cell and separates its contents from the cells in the other
side of the comb, please bear with me.
The simplest arrangement would be a flat vertical wax sheet
on which all the cells abut, but that is not at all what it is like in fact.
Instead, the base of each cell is a shallow cone or dimple, formed of three
congruent rhomboidal faces, that protrudes into the other layer, those faces
being shared with three cells in the other layer. Unlike some modern expensive
toys that do it all for you, this blog will leave you the fun of imagining
that, but the diagrams below may help. The clue is that the separating wall
zigzags shallowly as it passes the conical cell bases protruding alternately
from each layer. It is by no means flat.
One might assume that it evolved that way because it is
stronger, but the double layer of tessellated cells is pretty strong anyway.
The answer - worked out by the famous Swiss mathematician Samuel Koenig at the
request of the French naturalist René Antoine Ferchault de Réaumur in the early 1700s
– is that such a structure holds the maximum amount of honey for the least
quantity of wax, wax being an energy-intensive substance for bees to make. A
flat wall would use more wax to hold the same honey.
You may say, not much more! Not enough more to matter, surely? But if I
tell you that it is a species characteristic of honey bees, differentiating
them from other related bees, then I think you’ll have to agree that it must be
the product of evolution. You may still say - so what? To me it illustrates the
extraordinary length of time that has been available for bees to subject to
natural selection various types of wax comb design through the aeons, so that
the genes for the more adapted cell bases could end up in today’s honey bees,
and not those for flat bases instead. It’s not as though bees think, for their
accumulated “brain” is about the size of a pin head, so it hasn’t happened with
the speed that cultural evolution happens in us. It has taken … just as long as
it takes. And it has cost all those less successful plans in the genes – maybe
brilliant in other aspects – that have gone to the wall on the way, through
being borne by just a few fewer bee colonies each generation until the genes
and the plans were lost.
To modify Blaise Pascal: “Le silence eternel de ces temps infinis
m’effraie!” It may have
taken some 10 million years.
Compare it with our own cultural evolution. Less than one thousandth of
that time ago, we were still hunter-gatherers, for whom the response to any
degree of overcrowding was to move away towards less threatened resources.
Halve that time again, and we were just getting really good at slaughtering
each other in the competition for land, having had the brilliant idea of
agriculture. And now, that system has been such a successful cultural evolution
in terms of population that we are running out of resources, out of land, and
yet are still inventing better ways to slaughter each other ( – including
recently such bogus excuses as the “responsibility to protect” to get over the
sanctity of national boundaries).
What makes this even more potent is that any suggestion that we have
taken a wrong direction is immediately quashed by another, parallel
evolutionary quirk we have evolved – the overwhelming gender imbalance in
humans that predisposes us inexorably to warfare and militarism. And there may
be a third element in the fateful pattern - that capitalism seems on a par with
masculinity in driving us into incessant conflict.
The bees may have had a thousand such blips – or evolutionary wrong
directions – during their progress, when seemingly brilliant types of comb and
shapes of cell have had to run their courses in order for the flaws in them to
manifest themselves. And they have arrived at this present successful type,
with a tri-rhomboidal base, and this is even now being tested by nature to see
whether it is equal to the challenge - of mites, or of humans or of some of our
spin-offs, such as pesticides and climate change, or simply of human
interference in general with bees.
In comparison, our combination of agriculture, warfare and aggressive
gender imbalance may be just one little blip of thousands to come before we can
say we are as soundly based as the honey bee – if we survive all the blips. And
we won’t ever have been blown back
into the stone age, for there is no backwards for evolution, only forwards –
only it may not be our current idea of forwards at all.
This is uncomfortable territory for us all. On Saturday, 16th
February at 11 am. academic Cynthia Cockburn will be talking in the Curve at
the Norwich Forum on “Towards a Different Common Sense”. Among the different
senses she may tackle are those that concern militarism, gender and
capitalism. (The bits about
hunter-gatherers and agriculture are at least partly my own; about bees very
much the bees’ own.)
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