ABSTRACT
This chapter takes a very broad view of populations. Population studies by their nature consider large numbers of individuals, which leads to an averaging of individual variability. Thus, in simplified growth models, all individuals or members of the population are essentially the same, and one studies their collective behavior. An unsolved problem regarding population dynamics is the formulation and analysis of models for so-called metapopulations. While the growth of a homogeneous population is interesting in many respects, the range of likely dynamics is somewhat limited. In the Leslie model, the birth rates within a population typically differ by the age of the mother but they are constant over time within each age class. In the simplest case of an interaction system, the individuals of two populations do not influence each other much, except that they might compete for the same resources. The simplest example may be a mixture of two exponentially growing bacterial populations with different growth rates.
