In the logistic growth, per capita growth rate (r) depends on population size (N) and how close it is to carrying capacity (K). 'r' is the per capita rate of increase for a particular species under ideal conditions, and it varies from species to species. For instance, bacteria can reproduce much faster than humans and would have a higher maximum per capita rate of increase. The maximum population growth rate for a species is called its biotic potential. 'r' represents the intrinsic growth rate of a population.