The evolution of plant cultivation by ants

Outside humans, true agriculture was previously thought to be restricted to social insects farming fungus. However, obligate farming of plants by ants was recently discovered in Fiji, prompting a re-examination of plant cultivation by ants. Here, we generate a database of plant cultivation by ants, identify three main types, and show that these interactions evolved primarily for shelter rather than food. We find that plant cultivation evolved at least 65 times independently for crops (similar to 200 plant species), and 15 times in farmer lineages (similar to 37 ant taxa) in the Neotropics and Asia/Australasia. Because of their high evolutionary replica-tion, and variation in partner dependence, these systems are powerful models to unveil the steps in the evolution and ecology of insect agriculture.

Automated summary

A recent discovery in Fiji shows that ants engage in plant cultivation primarily for shelter rather than food. This behavior has evolved independently at least 65 times for crops and 15 times in different ant species. Studying these systems offers insights into the evolution and ecology of insect agriculture.