Linepithema iniquum workers from different colonies fighting. Morretes, ParanĂ¡, Brazil
Pheidole minor workers spread-eagle a Tetramorium (aculeatum - group) forager that has strayed into their territory. Kibale forest, Uganda
A native green tree ant dispatches a worker of a non-native species, the yellow crazy ant, in tropical Australia. In nature such fights typically go the other way; yellow crazy ants are rapidly displacing many species of native ants. Cairns, Queensland, Australia.