Ecosystems and Economics

Abstract

That populations of single species in simple environments may exhibit oscillatory patterns over time has been well understood since first being documented experimentally for sheep-blowflies by Nicholson (1933) and by Elton (1942) for small mammals in boreal environments. In the latter case the most famous example is the four year cycle of lemmings. Keith (1963) has documented the existence of ten year cycles for other boreal, fur-bearing mammals such as musk- rats. Of course the single species model strictly holds only in a laboratory context.

“She says, “I am content when the wakened birds, Before they fly, test the reality Of misty fields, by their sweet questionings; But when the birds are gone, and their warm fields Return no more, where, then, is paradise?”” Wallace Stevens, 1947 “Sunday Morning”