An ant colony consists of a series of underground chambers connected by small tunnels. There are rooms for nurseries, food storage, and mating. The colony is built and maintained by legions of worker ants who carry tiny bits of dirt in their mandibles and deposit them near the exit of the colony, forming an anthill. Food is carried in, stored, and rationed by workers.
Hymenoptera is one of the larger orders of insects, comprising wasps, bees, and ants. Ant colonies are “eusocial” – a zoological term meaning an advanced level of social organization in which a single female or caste produces the offspring and nonreproductive individuals cooperate in caring for the young. And ants are very much like those found in other social Hymenoptera, though the various groups of these developed as socially independent through “convergent evolution.” Convergent evolution is the independent development of similar adaptations to similar environmental conditions by
unrelated organisms; examples of convergent evolution in non-insects include fins (for fish, aquatic vertebrates) and flippers (for dolphins, mammals).
Ant eggs are laid by one or sometimes more queens, the largest ants. The queens’ task is to produce more offspring. Most of the eggs laid by the queens grow up to become wingless, sterile females. These are the “workers.”
French researchers compared the proportion of male eggs laid by the queen (primary sex ratio) with the proportion of males who reach adulthood (operational sex ratio) in Iridomyrmex humilis – a dark ant native to Argentina. The striking conclusion: the operational sex ratio is less than the primary sex ratio, meaning workers eliminate useless males, reflecting that any power struggle in the anthill is clearly female dominated.
Periodically, swarms of new winged queens and males mate. The males die shortly thereafter; the surviving queens occasionally return to their old colonies or found new ones. Queens can live 20 years or more.
For more than 50 million years, ants have reigned over five continents, constructing empires and sprawling megacities with millions of inhabitants. They developed the concepts of social order, collective activities, and state functions long before primates appeared on Earth. To date, myrmecologists from around the world have catalogued more than 20,000 species of ants on the planet
But the most fascinating aspect of ant life is ants’ incredible socialization. A closer study of ant colonies reflects an extraordinary level of organization, comparable to that of humanoids. To sustain such a level of organization, these three-brained insects developed a complex glandular system that allows the citizens of a colony to communicate chemically. Through these pheromones, a queen can communicate with her subjects, young reproductives can stimulate their partners erotically, and workers can warn of an advancing army.
Ants are very much like humanoids except for one meritorious distinction – instead of sending their youth, they send the sickest and oldest ants off to war.