The value of lambda for a population that has an equal proportion of males and females and produces on average one offspring per year for each pair of parents, assuming no mortality, would be:
a. 1.25
b. 0.5
c. 1.5
d. 2.0
e. 1.0

The correct answer is option C, that is, 1.5.

Explanation:

As the population exhibits an equal ratio of males and females and the rate of mortality is zero, thus, assuming the following values:

N0 = 2, that is, population at present considering a solitary couple.

N1 = 3, that is, population at the end of one year comprising the offspring

Presuming that the population is demonstrating discrete exponential growth/geometric growth one can use the formula:

\lambda (finite/geometric rate of increase of a population) = \frac {N1} {N0}

\lambda = \frac {3}{2} = 1.5

Thus, the value of lambda for the given population is 1.5.

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