The social dynamics of ant colonies are complex setups, requiring sophisticated mathematical models to map them out. There is a strict hierarchy of jobs that are determined by age: sterile workers, reproductive males, and reproducing queens. Under this hierarchy, the colonies’ main collective goal is to reproduce and grow their population as much as possible whilst protecting their queen.

Normally in ant species, individuals are born into this caste system with little room to progress up the social ladder. Though a particular type of ant, the Jerdon’s jumping ant (Harpegnathos saltator) sets up its community differently. A new study published in Cell found a hormonal trigger can activate their ovaries and produce a series of changes to their neuronal network. When worker ants receive this signal, their role in the colony is reprogrammed, transforming sterile individuals into reproductive queens.

Scientists figured this out by completing a series of genetic experiments on ant neurons. Their findings indicate that the presence of two hormones activates a single gene called Kr-h1. Easily turning the pathway to queendom on or off depending on the hormonal presence like a light switch. It was also found that queens could revert back to workers when this gene was deleted and turned off in their system.

This plasticity of the brain in response to the environment is common in many animal species including humans, for example when we go through adolescence or trauma. Though in the case of Jerdon’s jumping ants, this transformation is particularly extravagant for the fact it is under the control of a single gene. The exact mechanisms for the process have not yet been mapped out, but understanding neuronal processes in simpler organisms is likely to give clues to understanding them in humans. This may also lead to potential application to neurological disease treatment.

Source study: Cell – Kr-h1 maintains distinct caste-specific neurotranscriptomes in response to socially regulated hormones