The yellow crazy ant looks like a common ant, around four millimeters in length, but it's yellow (duh).
The ant is native to Africa, but in recent years has spread to the tropics, where it is considered a threat to local ecologies. Although they prefer to nest in the earh, the ants are found everywhere, from tree tops to deep underground.
Heh. The yellow crazy ant eats just about everything... vegetation, animals, whatever. They've taken complete control over one half of Bird Island in just eight years, and have killed an estimated 3 million red crabs on Christmas Island in just the past few years. They've also been known to kill pigs and dogs.
They just eat, breed, and move. They can consume around a square meter of rain forest a day. On Christmas Island in particular, the ants move into red crab burrows, kill the crabs, and then set up shop. These are kind of like those ants from that McGyver episode that ate one guy alive and almost had MacGyver until he flooded a big ditch, started a big fire, and flew away in a two-prop plane. These are some bad ants.
The typical queen-worker relationship seen in ants and bees and the like, but they form advanced supercolonies with multiple queens.
They don't seem to have any problems with yellow crazy ants in their native Africa. It's only when they get transplanted to another area do they go berserk.
Well, they were accidentally introduced to Christmas Island in the 1930's by traders, and didn't go psycho until a few years ago. Scientists still don't know why, but are leaning towards mass extermination to stop the ants from doing what they do best - putting species on the endangered list.
The yellow crazy ant is named for its rapid, frenzied movements.