Smithsonian.com

Photo: MalcomNQ

In 1937, the naturalist Eugene Marais wrote in The Soul of the White Ant, “I must admit that intelligence and thoughtfulness, as we humans understand these qualities, never entered my mind in connection with the termites.”

But perhaps Marais would have thought differently had he learned of the latest extraordinary sacrifice termites make for the greater good of the colony. In French Guiana, older members of termite society sense their usefulness to the colony is wearing thin. Their mandibles are no longer sharp enough to work as effectively as they did in their younger days, and they’re not as efficient at foraging or nest maintenance as their more youthful comrades. After a lifetime of servitude, they altruistically offer up the only thing they have left: their lives.

Nature reports on the suicidal strategy:

The “explosive backpacks” of Neocapritermes taracua, described in Science today, grow throughout the lifetimes of the worker termites, filling with blue crystals secreted by a pair of glands on the insects’ abdomens. Older workers carry the largest and most toxic backpacks.

When the nest is attacked by invading termite colonies, the old workers answer to the call of duty. They rupture their own toxin-laced abdomens, sacrificing themselves in order to take down the enemy.

The researchers say suicidal sacrifice is common amongst honey bees, termites and other highly social insects, though in this new case the toxic mixture’s sophistication is “remarkable,” they say.

As they told Nature,

“This kind of adaptation would not evolve in a solitary context; this shows the power of eusociality, and why these insects are so successful.”

Watch this old worker’s ultimate sacrifice:

More from Smithsonian.com:

Termite Bellies and Biofuels 

Termites as the Ultimate Fighting Machines