Meanwhile, in South America, acacia trees rely on ants to defend them from weeds, pests, and grazers. In return, they give their bodyguards sugary snacks to eat and hollow thorns to live in. It looks like an equitable relationship, until you realise that the tree laces its food with an enzyme that stops the ants from digesting other sources of sugar. The ants are indentured servants. All of these are iconic examples of cooperation, found in textbooks and wildlife documentaries. And each of them is tinged with conflict, manipulation, and deceit.
