I’ve talked about invasive ants before; in particular, I have talked about the nasty invasive fire ants (Solenopsis invicta), whose name means “invincible” or “unconquered”. I studied those guys when I worked for a brief time with Walter Tschinkel at FSU. (Good times, but lots of blisters from fire ant stings.)
But as vicious and well known as the fire ants are, they are not the only vicious invasive ant species. There are in fact a number of ant species, known as “tramp ants”, that hitchhike on human transportation, establish readily, and spread widely.
Here are a few other terrifying invasive ants.
Rasberry Crazy Ants (Nylanderia fulva) — The New York Times had a great (and terrifying) post about this a few days ago, including this beautiful photo.
So named for their erratic and even “psychotic” behaviour, the crazy ants are tiny, but numerous. Millions of them infest homes in Texas, and they love electricity: televisions, laptops, cars…their known for shorting out all sorts of electrical systems. Thus, they cause extensive damage and seem completely unstoppable.
The Yellow Crazy Ant (Anoplolepis gracilipes) — These guys are famous for the detrimental ecological impacts they are having on oceanic islands. Specifically, they have a detrimental impact on native hermit crabs on Christmas Island (McNatty et al. 2009).
Why are they so detrimental? Well, like other invaders, they spread quickly and are generalists, meaning they eat just about anything. This means they outcompete with native species for food resources due to their abundance.
The Argentine Ant (Linepithema humile) — According to this awesome Radiolab episode, the Argentinian ant is vicious because it kills anything unfamiliar. Like white supremacists, or any other racial purists, they do not interbreed and they do not mingle. There are lines of millions of dead ants where colonies meet.
This has resulted in the fascinating phenomenon of three “global colonies” of pure genetic descent from the original colonies introduced from Argentina. They occupy Europe, North America, and Japan. One colony stretches for more than 900km in California.
The Fire Ant (Solenopsis invicta) — I don’t feel like I need to say much about the invasive fire ant, the scourge of the south. This ant is very noticeable because anyone who accidentally disturbs a mound is swarmed by thousands of ants whose stings leave white pustules on the skin. I had an earlier post about some of their ecological impacts.
They are now distributed globally. But they do have some good effects…for example, they inspired E. O. Wilson.
The Little Fire Ant (Wasmannia auropunctata) — Also known as the electric ant, this tiny little bugger actually has a pretty painful sting. In spite of its diminutive size, in fact, the little fire ant can have extremely detrimental impacts on native species, such as the Galapagos tortoises (poor things are already having a hard time).
The Bigheaded Ant (Pheidole megacephala) — So named because of the large heads and mandibles of the soldiers (which are about twice as large as the workers), the Bigheaded Ant is a prime example of how these introduced species can achieve competitive asymmetry through sheer abundance. According to one study, this species was found to be “11–62 times greater in abundance than that of all native ants in uninfested sites, corresponding to a 4- to 18-fold increase in ant biomass” (Hoffmann and Parr 2008).
Though the ecological impacts are still unknown, the abundance and diversity of other invertebrates was found to be much lower in invaded sites.
Tramp ant impacts
Although individually very small, these tramp ants can have huge ecological and economic impacts, and the species listed are considered to be among the worst invaders worldwide. The fact is that their ability to act as a colony makes them a serious threat. They can spread rapidly, establish anywhere, and outcompete native species for resources. (Sort of like humans, I guess.)
Hence the inspiration for the villains in Ender’s Game!