Monogyny

Monogyny means "one queen". A monogyne colony has a single queen who lays all the eggs, and when she dies, the colony can't replace her. Without new workers, it slowly fades away.

Many of the most popular species in ant keeping are monogyne, including Lasius niger, Messor barbarus, Crematogaster scutellaris, Tetramorium caespitum and Lasius emarginatus.

There's one interesting exception. In some monogyne species, especially after a very large mating flight, several queens can start a colony together. This is called pleometrosis, and it can give the colony a faster start. But it rarely lasts: once the first workers arrive, the queens usually fight, or the workers eliminate the extra ones, until only one queen is left.

In practice

• Never try to merge two queens of a monogyne species, or add a new queen to an existing colony. It almost always ends with dead queens.
• If you caught several queens of the same species, give each one its own test tube setup.
• If you do try a multi-queen founding, keep a spare setup ready and watch for aggression once the workers emerge.
• Since everything depends on one queen, a stable, quiet environment is the best thing you can give your colony.