Intraspecific CompetitionGoals (part 1):• Understand steady-states• Understand density dependent population

regulation• Be familiar with the logistic equation• Assumptions of logistic model• Be familiar with examples of logistic growth

Intraspecific CompetitionGoals (part 2):• How are time lags incorporated into the

logistic model?• Qualitatively describe how time lags affect

population growth with the logistic model• Discrete vs. continuous form of the logistic

model – built in time lags• How do populations with different r respond

to variations in carrying capacity?

Logistic Equation – Sigmoid Growth

Logistic

ExponentialExponential

Logistic

These figures compare dN/dt and [(1/N)(dN/dt)] for the logistic and exponential models. They might help you to conceptually understand the difference between the two with respect to population growth and the intrinsic rate of growth as population size changes.