Imagine, if you will, a tiny creature with the ability to invade your body, hijack your cells, change your DNA, and modify you physically and behaviorally to suit its own devious goals. Sound like science fiction?
Maybe, but it's also the modus operandi of the real-life parasitic organisms that live among, and inside, the rest of us animals. While some parasites, in their quest for survival and propagation, may live undetected in the bodies of their hosts, others can cause sickness or death.
Some of the world's most pernicious and persistent diseases are caused by these supremely successful and sophisticated organisms. But according to evolutionary biologists, parasites have also played a significant role in shaping the human species -- including why we use sex to reproduce. (Nice job, little friends!)
Just when you thought it was safe to go back in the water, Jim McKerrow returns to Ask a Scientist with more strange and wonderful tales of parasite biology.
Note to the squeamish: beware!
Jim McKerrow is Director of the Sandler Center for Research on Parasitic Diseases.