PNAS 115, 5504–5509 (2018).

Within one colony, social hymenopteran lifespans can span more than a hundred-fold difference between caste members. In a new study with termites, investigators compared reproductive caste members (kings and queens) to working caste members (majors and minors) using transcriptome sequencing of head tissues. They discovered that majors, who typically have shorter lives due to performing outside duties, showed elevated expression of transposable elements (TE) and TE-related genes in old majors versus young majors. Alternatively, genes known to suppress TE, termed PIWI-interacting RNAs, were reduced in old majors. Reports from other organisms also link elevated TE activity to increased aging, with TE believed to randomly insert into genes and regulatory regions, thereby disrupting function. The authors liken a colony to a superorganism, where the majors are the disposable soma that is not maintained due to its’ reduced longevity.