Social Spacing as an Intermediate Scale in Models of Population Dynamics
Based on the Behavior of Individuals
Abstract:
A model with multiple time/space scales will be presented that
permits population dynamics to be derived from individual behavior. First
is the capture event scale, in seconds; next is the optimal foraging scale,
in hours, that expresses the yield from the capture scale; then the social
spacing scale, in days, during which the positions of the individuals
relative to each other are established; and finally, the population and
species-interaction scale, in weeks, is the scale at which eggs are
produced. Because these four scales differ in speed by an order of
magniture or more, we can proceed
in a hierarchical way through them, one by one. Fast processes keep up with
slow ones, and slow processes determine the 'environment' within which the
fast processes operate.
This procedure leads to a population-dynamic and species-interaction model
that can be used to revisit the key theoretical issues of community
ecology, such as coexistence and niche differentiation, instead of relying
on the logistic and Lotka-Volterra equations
that were used early on in community theory.
Assigned reading
Chapter 1 of Roughgarden, 1995, Anolis Lizards of the Caribbean,
Oxford University Press.