We’re always marveling at the complex and wondrously efficient social organization found in the insect kingdom.
Who wouldn’t want to model a democracy after ingenious ants that vote for their leaders by swapping spit? And we could learn a few agricultural tricks from termites.
But when the time comes for termites to put down their plows and go to war, they demonstrate possibly the coldest social imperative of all.
Senior citizens are the first in line to die.
That’s right. While humans — and many other mammals — pride themselves on respecting the elderly, termites see old folks in a different light.
Basically, old termites, male and female alike, are used as cannon fodder.
According to a study published this month in Royal Society Journal Biology Letters., the riskiest jobs in termite society are assigned to the oldest members of the colony. That includes going to war against ants and other termite colonies.
For the study, Japanese researchers built a fake nest and parachuted seven termites — two soldiers and five workers — onto the scene.Then they threw a marauding ant into the mix. In almost every one of the experiments, the senior soldier took a position at the colony gate, while the older female soldiers sallied forth to engage the ant.
The younger the soldier, the closer they would stick to the nest, as a final line of defense against invaders.
"These results demonstrate that termite soldiers have age-based task allocation, by which ageing predisposes soldiers to switch to more dangerous tasks," researchers noted in the study.
And while it may seem like the cruelest reward for a lifetime of civic service, that cold, hard determination is eminently logical. Termite society, like many hive-minded societies, is sharply divided among caste. Every member is born to serve a specific purpose to ensure the colony — and its precious queen — flourishes.
Termites protecting their queenWhether they're workers or soldiers, termites always close ranks around their precious queen. (Photo: Chaikom/Shutterstock)
Termites are divided into workers, reproducers and soldiers. The soldiers are sterile so their contributions to termite society are limited to defending and claiming turf from hostiles. They’re actually built for battle — with super-sized heads they use to block entry points to the colony and gaping mandibles to impale foolhardy invaders.
But what do you do with an old soldier — one whose once-feared "mandible strike" isn’t quite so quick any more? Can’t work. Can’t breed.
So it’s off to fight the eternal war with those accursed ants.
In that way, a colony gets the double benefit of sloughing off its weak and infirm, while maximizing their contributions to the bitter end.
"This age-dependent soldier task allocation increases the life expectancy of soldiers, allowing them to promote their lifetime contribution to colony reproductive success," researchers noted.
Let’s not be quick to judge. It’s hard to gauge the effectiveness of the Old Fogey Brigade. Maybe they give those ant hordes a good cane-stomping. Maybe they’re heroes. But we do know there are no medals of valor for termites. No trumpets sounding from the battlefield.
And for that sacrifice, old soldiers, we salute you.
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