Question
Describe the logistic population growth.
✓
Answer
Logistic Growth : No population of any species in nature has at its disposal unlimited resources to permit exponential growth. This leads to competition between individuals for limiting resources. Eventually, the 'fittest' individual will survive and reproduce. 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 in relation to time (t) results in a sigmoid curve. This type of population growth is called Verhulst-Pearl Logistic Growth and is described by the following equation;
$dN / dt =\frac{ rN ( K - N )}{ K }$
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 sooner or later, the logistic growth model is considered a more realistic one.
(A) When responses are not limiting the growth, plot is exponential.
(B) When responses are limiting the growth, plot is logistic, K is carrying capacity.
$dN / dt =\frac{ rN ( K - N )}{ K }$
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 sooner or later, the logistic growth model is considered a more realistic one.
(A) When responses are not limiting the growth, plot is exponential.
(B) When responses are limiting the growth, plot is logistic, K is carrying capacity.
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