Last fall I came upon this veritable drift of dead male fire ants, piled up along the sidewalk outside a large ant nest. The worker ants there didn’t seem to know what to do with this sudden overabundance of dead bodies and were piling them up in heaps at the sidewalk edge and stuffing them into sidewalk cracks.
Fire ants, like many social insects, mate in nuptial flights, swarms wherein thousands of winged sexual ants (alates) mate on the wing. Afterwards, the females drop to the ground and shed their wings and become foundress queens, seeking out a place to rear their first brood. The males drop to the ground and die.
A male ant is pretty much a very streamlined sperm delivery device. They hatch from unfertilized (haploid) eggs, they have big muscular backs for wing muscles, and tiny heads because they don’t need much in the way of brains. Prior to their one and only flight they also void their gut contents and fill their abdomen with air to make themselves more aerodynamic (Wilson, “Insect Societies”). After their mating flight the males may wander briefly on the ground for a period before their body inevitably shuts down and they die.
The female alates, however, can go on to live more than twenty years. Deborah Gordon has data on some of her long term study colonies of harvester ants going back to 1985. Those colonies are as old as me!
- Nuptial Flights: The Sad Plight of Male Ants
- Queen Ants — Founding a New Colony
- A Heap of Queens — Foundress Fire Ants
- Swarms of Fire Ants