Supercolony

Normally, ants from different colonies treat each other as enemies, even if they belong to the same species. A supercolony breaks that rule. It's a huge network of nests, each with many queens, where the workers don't fight each other and move freely from one nest to another, as if they were all part of the same family.

The most famous example is the Argentine ant. In southern Europe, researchers found a supercolony that stretches for about 6,000 km (3,700 miles) along the coast, made of millions of nests and billions of workers. Similar giant networks of this species exist on other continents too.

Supercolonies are mostly formed by invasive, strongly polygynous species. Because they don't waste energy fighting their neighbors, they can grow to an incredible size and push out native ants, which is why they're a real problem for local ecosystems.

In practice

• Supercolony-forming species aren't good pets. They spread fast, escape easily and can become a serious problem if they get out.
• Never release ants into the wild, and avoid buying invasive species, even if they look easy to keep.
• If you live where the Argentine ant is invasive, double-check that the queens you catch belong to your target species.
• For a beginner, a monogyne local species like Lasius niger or Messor barbarus is a much better choice.