In our hyper-hygenic society, we tend to cringe at the thought of such parasites as lice and fleas. With the proper perspective, though, these look positively benign. You may remember the motion picture "Alien" that includes a scene of a horrible creature bursting out of the chest of one of the characters. This is the type of thing I'm talking about.
Take, for instance, the ant-decapitating flies of the genus Apocephalus, with a number of species in the Southwest. These are tiny things, even compared to ants. Lighting on an ant, the fly will deposit an egg into the ant's body. Depending on the fly species, the egg is laid either in the abdomen, thorax, or head. Hatching, the resultant larva forces its way through the ant's tissue, if necessary, to get to the head. Once there, the larva feeds on the soft tissues within the hard capsule forming the head. Eventually, the flesh-depleted head capsule falls off, sometimes while the ant is still alive and walking around. Ready to settle for a few lice and fleas?
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.