Veromessor pergandei is one of many species of “Harvester Ants”, getting their name from their habit of foraging for seeds, plant material, etc and storing it all in underground chambers called granaries. Following a chemical trail for up to 60m, a colony of tens of thousands can move a lot of seed, some of which gets consumed and some will end up germinating which is a benefit for the plant. (click images for larger version)