Science

A June 2026 study in BMC Genomics by Blasi, Schwolow, Darras, and Foitzik (Johannes Gutenberg University Mainz) examined what happens molecularly when the tapeworm Anomotaenia brevis infects worker ants of Temnothorax nylanderi.

Image: Phys.org - Tapeworm hijacks worker ants, giving them queen-like metabolism and longer lives

The core finding: infection doesn't simply make ants sick. It reprograms them in a tissue-specific way. In the fat body, infected workers shifted toward a queen-like gene expression profile, with overlapping activity in genes governing metabolism, immune response, stress resistance, and aging. This mirrors the biology of queens, who can live up to 20 years compared to workers' one or two.

In the brain, the picture was different. Infection broadly suppressed neuropeptide signaling, including tachykinin, short neuropeptide-F, allatostatin-A, orcokinin, CAPA, and diuretic hormones, along with their receptors. This dampening of behavioral signals likely explains why infected workers become sluggish, which benefits the parasite: slower, longer-lived ants are better vehicles for transmission to the tapeworm's definitive host, the woodpecker.

One hypothesis the researchers tested and ruled out was classical neuropeptide mimicry, where the parasite produces peptides resembling the host's own. The parasite's peptides weren't sufficiently similar to the ant's. "The data rather suggest that the parasite influences the ant indirectly by intervening in the host's own regulatory networks," said first author Giulia Blasi, per Scientific Frontline.

The parasite also appears to exploit the insulin/IGF-1 signaling and juvenile hormone pathways that normally govern caste-specific aging, per Semantic Scholar.

Sources: BMC Genomics, Scientific Frontline, Semantic Scholar