Qualitative Variation in Plants and Insects: Effect of Propagule Size on Ecological Plasticity

Abstract

The functions of plant and insect propagule size are considered in the context of environmental heterogeneity. Qualitative phenetic characteristics associated with individuals and populations, such as development time, reproductive capacity, and survival probability, are generally correlated with propagule size. Optimal propagule size, i.e., that which confers increased fitness, varies with environmental conditions. Thus, the traditional view that progeny from large propagules are qualitatively superior or more vigorous is subject to qualification. Phenetic variation appears to result in production of progeny that are able to cope effectively with unpredictable but recurrent instabilities in their environment.