We're all proud of our brains. Certainly our ability to think and plan far outshines even our nearest relatives, and these abilities have enabled us to increase our numbers and hold sway over most of earth's organisms; even to the point where decisions made by humans affect literally millions of species of plants, fungi, and animals for better or worse.
Such hegemony does not come cheap. As we evolved a larger brain,
various problems had to be solved. The brain is enormously active, despite what you may
think of some of your fellow beings, producing heat that had to be carried away to
prevent injury and requiring enormous amounts of energy. Our caloric requirements
climbed drastically, to the point where it's estimated that up to 25% of our energy
intake goes to feed the brain. This of course tends to take away food from the rest of
the body. So, we have a dilemma: Do we describe this as a brain drain or look on the
bright side and consider a quarter of what we eat is brain food?
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.