A population growing in a habitat with limited resources show initially a lag phase, followed by phases of acceleration and deceleration and finally an asymptote, when the population density reaches the carrying capacity. A plot of N (population density at time t ) in relation to time (t) results in sigmoid curve. This type of population grown is called Verhulst-Pearl Logistic Growth and is describes by the following equation : dN/dt=rN(KK−N) where, N= Population density at time t, r= Intrinsic rate of natural increase K = Carrying capacity Since resources for growth for most animal populations are finite and become limiting soner or later, the logistic growth model is considered a more realistic one.