From Scientific American:
Some ants live longer than others—way longer. And the mapping of the first full genome sequences of ants helps to reveal how two ants from the same colony, and with much the same genetic material, can have such different life histories. The work may also provide insights into longevity in another social species with which ants share about one third of their genes: humans.
Researchers sequenced the genomes of two ant species: Jerdon's jumping ant (Harpegnathos saltator) and the Florida carpenter ant (Camponotus floridanus), which have quite different levels of social—and hence, biological—mobility. Carpenter ants live in large colonies that revolve around a queen that lays all of the fertilized eggs. Once the queen dies, the colony perishes as well. Jerdon's jumping ants, on the other hand, have smaller colonies in which worker ants can replace the queen after she dies. These so-called gamergate queens change physically and behaviorally as they take on the queen's duties. All of these ant castes seem to start with the same basic genetic blueprint, yet end up looking—and behaving—very differently. Scientists point to epigenetics, the change in gene expression (rather than direct alterations in the DNA code), as a likely explanation.
More here.