As a result, at this population size, population growth is highest. Now we have two terms multiplied by each other. If r m were zero, it would mean that the maximum possible growth rate for a population is zero. Such a population would be dead before it could get started so this situation is not ecologically relevant. So the maximum growth rate is at half the carrying capacity.
Logistic growth turns out to be a good general model of population growth.
It fits, at least roughly, the pattern of population growth seen in many different species. Some species, however, show different patterns. In the next lecture we will consider how we can make the logistic growth model a little more accurate for specific species, realizing that as we do, we make it less general.