Readings
		Turco, chapter 1
		Robert Costanza, et al., "The value of the world's ecosystem services and natural capital," Nature, Vol. 387, pp. 253-260 (15 May 1997).
		John Tierney, "Betting the planet," New York Times Magazine, Dec. 2, 1990.
		Paul Ehrlich's version of the bet
		Class notes (covers same material as lecture slides, in narrative form)