So Flying Ant Day (as it has been colloquially termed) is actually the nuptial flight of an ant, and it is very important in the reproductive life cycle of the colony. A colony of ants will produce winged ants of both genders, male and female (queen). These winged 6-legged critters stay within the colony until the external conditions are optimal (generally a clear day with no rain). Interestingly, colonies in the same area synchronise the release of their winged queens and males, to coincide, in order to avoid inbreeding of the colony.
|A female winged Carpenter Ant|
So when queens and males from the same colony leave, they scatter to ensure outbreeding will occur as much as possible. Like bees, ants release pheromones and the queens release this potent chemical scent to attract a mate.
Once mating has occurred the queen ant will land and remove her wings, and attempt to create her own colony. Although this process appears to be relatively a simple procedure, the actual chances of a successful colony being created is very low. The ants have to outcompete a number of factors to survive, which can act as a selection pressure. These factors could be the climate, predators, environmental occurrences and the raising of infant ants (larvae) into workers to name a few. Thus when a queen is successful in establishing a new colony, she is passing advantageous genes onto her offspring, making stronger and fitter ants in the next generation.
|A winged male Carpenter ant|
So the next time you witness flying ant day, don't swat away the little bugs, leave them to find their true mate and create a new colony of ants, who will be ready to take flight in the following season.
Explorer Fact: Termites and some bee species take part in a nuptial flight and their flight will often coincide with with the flight of the ants, often to confuse predators and ensure a greater chance of success.