PARENT SESSION
Oral Session #11: Biodiversity and Ecosystem Function. Presiding: A. Downing.
Monday, August 6, 2001. 1:00 PM to 4:45 PM. Madison Ballroom C.

Efficiency and risk aversion in nature: avoiding chaos.

HANNON, BRUCE¹, O'NEILL, ROBERT², ^{1 2}

ABSTRACT- We assume that species behave efficiently and avoid the conditions that lead to their population collapse. Using a standard logistic growth equation, we show how the average value of the population drops as the growth rate exceeds 2, in a steady environment. In a fluctuating environment we show how the constraint on the growth rate is even greater. We delineate the limits on the growth rate for these different conditions, all of which are well below the level needed for what is often called chaos.

KEY WORDS: chaos, population, efficiency, risk