The parasite allows worker ants to live up to 20 years, matching the lifespan of the colony’s queen and far exceeding the usual 2 to 4 year lifespan of workers. Infected ants are smaller and lighter in color, but they smell like the queen, so the whole colony rushes to feed and care for them. Settled into this comfortable life, the infected workers don’t even bother leaving the colony. At the molecular level, she said, infected workers showed a profile that partly resembled the queen’s. Anomotaenia brevis is just one of many parasite species that manipulate their host’s behavior.