Termites are eusocial, but differ greatly in the genetics of reproduction.
The similarity of their social structure to that of ants is attributed to convergent evolution.
More than 12,500 of an estimated total of 22,000 species have been classified.
They are easily identified by their elbowed antennae and the distinctive node-like structure that forms their slender waists.
Their ecological dominance is demonstrated by their biomass: ants are estimated to contribute 15–20 % (on average and nearly 25% in the tropics) of terrestrial animal biomass, exceeding that of the vertebrates.
Ants vary in colour; most ants are red or black, but a few species are green and some tropical species have a metallic lustre.
By the Oligocene and Miocene, ants had come to represent 20–40% of all insects found in major fossil deposits.