Ignoring a low rate of mutation as a source of heterogeneity, bacterial division results in clonal
expansion, with the daughter cells considered to be similar if not identical to the parent cells.
Collectively, these cells are called a population. However, bacteria rarely exist as a single species
within any one habitat but, instead, are usually found as collections of different species called
communities, where each particular species will exist in a particular niche but may well contribute to
the maintenance of the entire community (e.g. syntrophism).
Interactions between microbial communities may have a negative (e.g. competition) or positive (cooperation) outcome. The interactions will be between both a single population (i.e. between members of
the same species) or between members of different populations. Typically, co-operation will occur at
low population densities, whereas competition will dominate at high population density. The net effect
will regulate …