Worker polymorphism in the marauder ant Carebara affinis. Pictured here is a single supermajor worker, two major workers, and full complement of minor workers. These insects are all sisters and are essentially genetically identical, their different morphologies a result of developmental plasticity. Rossville, Queensland, Australia
Friend or Foe? Two workers of the tree ant Liometopum luctuosum check each other out. Mojave National Preserve, California, USA
Technomyrmex andrei feeds from a cookie bait laid out by the photographer. Kibale Forest, Uganda