Ecological theory

Abstract

The very large number of factors which operate simultaneously in nature (both biological and environmental) make it very difficult to do well controlled experiments. Thus the relationship between theory and experiment in ecology is much less well defined than in many other sciences. Much ecological theory is concerned with small number systems that can be modelled by means of differential equations. In the sense of Piatt (1964), ecology is but poor science as many of the basic theories and concepts turn out to be untestable (Murdoch, 1966). This point has been made more recently by Rigler (1975, 1982) and Peters (1976). Furthermore there is confusion between fact and concept (Ehrlich and Holm, 1962) and there is a strong tendency to explain proximate events by ultimate causes (Mayr, 1961). The distinction between proximate and ultimate causes lies in the inevitable temporal component which pervades all ecological process. In short, it comes down to whether or not a given community structure is the way it is because of present day (proximate) events like competition, or because of evolutionary (ultimate) causes that occurred in the distant past. To make things even more complicated it might be a bit of both (Williamson, 1981a)! Clearly one of the reasons why ecology has made little progress in the last twenty years in comparison to molecular biology, is the poor status of theory and experiment.