6 - Scramble and Contest Competition: What Is the Difference?

Summary

The idea of the distinction between the two types of competition was first recognized by A.J. Nicholson. Most standard textbooks of ecology refer to his idea. However, as I see it, the distinction has not been adequately understood. I show the nature of competition in terms of the reproduction curves, incorporating the generalized model developed in Chapter 5. A graphical representation of the variation in these curves reveals that the two types of competition form a continuum and no sharp line can be drawn between them. It reveals that each curve (with a particular set of parameter values) is comprised of the two elements, scramble and contest, of competition. I also show that the continuum can be extended further to include elements of sociality (benefits from the formation of group) such that we cannot draw a sharp line between competition and sociality.