Most of us on the internet are well aware that hackers quickly exploit any weakness in the system for their own advantage. Furthermore, we know that it's a never ending battle, for as attention is given to blocking vulnerable spots, new weaknesses are exposed—and indeed, often are created by our very protective efforts.
Much the same thing goes on in nature. Recent research has revealed a vulnerability in the White Cabbage Butterfly, where an evolutionary attempt to protect reproductive success has opened the insect to parasitism. Butterflies rely heavily on chemical signals during reproduction, including release of pheromones by the female to attract males. In the cabbage butterfly, the male transfers a chemical to the female that renders her less attractive to other males. It turns out, though, that a small parasitic wasp is attracted to the chemical and hitches a ride on the female to her egg-laying site. Having arrived at the newly laid eggs courtesy of the female, the wasp quickly lays its own eggs, parasitizing those of the butterfly. Some days you just can't win!
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Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a production of KTEP, National Public Radio at the University of Texas at El Paso.
Fatouros, N. E., M. E. Huigens, J. J. A. Van Loon, M. Dicke, and M. Hilker. 2005. Butterfly anti-aphrodisiac lures parasitic wasps. Nature 433:704.