I contributed a cover image! Although I am not on the paper:

Here is a quick view:

Understanding how flexible traits (plasticity) and stable genetic differences (balanced polymorphisms) evolve is a major question in biology. Fire ant gynes (pre-reproductive queens) are a great system to study this because they show both genetic and environmental influences on their traits.

There are two types of gynes:

1. Gynes with the Sb supergene → Lighter in weight, rely on worker ants to start a colony.
2. Gynes without the supergene (ancestral type) → Store more nutrients, can start colonies alone.

However, if the ancestral-type gynes overwinter (spend winter in the nest before dispersing), they develop traits similar to inversion-carrying gynes—becoming lighter and shifting their behavior to rely on workers.

To see if plasticity and genetic differences share common mechanisms, the authors

• Compared gene expression profile in brains and ovaries of overwintered vs. non-overwintered gynes.
• Found that plasticity-related genes were linked to metabolism and behavior.
• Discovered that some of these genes also vary between supergene types, especially in the ovaries.
• Identified genetic mutations in plasticity-related genes within the supergene, suggesting that a trait that was once flexible (plastic) may have become more genetically fixed over time.