“Attenborough
and the Empire of the Ants” is a fascinating documentary about ants, narrated
by none other than David Attenborough (at the ripe old age of 90). The
scientific name of the featured ant species is never mentioned – they are
simply referred to as “wood ants” and live in the Jura Mountains in
Switzerland. What makes them sensational is that their colonies don´t wage “wars”
against each other, something wood ant colonies otherwise do as a matter of
course. Rather, the Jura anthills form a constantly expanding “super-colony” with
millions of queens and even more worker-ants that all live at peace with each
other. Indeed, very often, several queens can be found in a single anthill.
Attenborough
claims that the ant queens are *not* genetically related to each other, which
strikes me as odd - they are all of the same species, so why don´t the gene
pools of the different lineages gradually mix as a result of swarming? If true,
this would seem to disprove “Hamilton´s equation”, according to which animals
should show altruism only towards their kin, although I suppose you could see
the Jura ants as an unusual example of reciprocal altruism instead. Besides,
the weird collectivism of the ants, where one colony functions as a virtual “super-organism”,
has always challenged evolutionary biologists more used to selection on the
individual level.
Later,
Attenborough reveals another remarkable fact about the Jura ants: many of their
colonies have dispensed with swarming altogether, the queens and winged males
mating inside the colony instead, after which the queens simply form a new
colony nearby. It was also interesting to note that the queens don´t seem to be
in control of anything – rather, they are herded by the workers, which
(somewhat flippantly) makes Attenborough say that the ants invented democracy!
“The Empire
of the Ants” also hints at a possible evolutionary explanation for the
super-colony. Usually, wood ant queens invade the nests of field ants, a
different species altogether, and “enslave” them. Ironically, this makes the
wood ants dependent on the existence of field ant colonies. The wood ant super-colony,
by contrast, is no longer parasitical and can therefore expand deep into the
Jura forests, including areas where no field ant has ever gone before. The
documentary ends somewhat ominously by Attenborough claiming that we may be
witnessing the first step in an ant “social conquest of Earth”.
On the web,
I found the claim that all Argentine ants *all over the world* form one vast
global super-colony, so who knows, maybe the “social conquest” has already
happened, it´s just that Homo sapiens haven´t noticed this time neither…
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