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Desert Diary


There is a lot of confusion between purposeful and mechanistic happenings. Of course, there always has been a lot of controversy about free will or the lack of it, but I guess we can agree here that purpose includes some level of consciousness. Yet, we find people constantly attributing purpose to all sorts of things, living or non-living, that couldn't possibly have consciousness. Indeed, this may be an innate characteristic of humans.

However, this also may be a consequence of our language in part. We're very apt to say things like, "That vine is climbing up the fence in order to reach the light". In reality, of course, that vine is reacting to the strictly mechanistic laws of nature: primarily chemical. Directional light affects chemicals such that plant cells alter their division and growth in a manner that turns the shoot toward the light. Other chemical reactions respond to touch receptors, such that the vine shoot has slower growth on the side touching the fence. The result? The vine twines around the fence post. No volition; it's all chemistry!
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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.