Question

Demographic stochasticity introduces random variation in population growth because

• A. changing weather conditions from year-to-year can result in good and bad years for reproduction.
• B. the discrete nature of births and deaths introduces uncertainty in population parameters.
• C. per capita birth rate in a population decreases with an increase in population density.
• D. of predictable time lags between change in population size and reproduction.

Hint:

Demographic stochasticity refers to random variations in population size due to births and deaths, especially in small populations.

Answer 1

The Correct Option is B

Demographic stochasticity refers to the random variation in population growth due to the discrete nature of births and deaths. In small populations, this randomness becomes more pronounced because the effect of each individual birth or death can significantly affect the overall population size.
Option (A), while true that changing weather conditions can affect reproduction, refers to environmental stochasticity, not demographic stochasticity.
Option (C) describes the effect of density dependence, where the birth rate decreases as population density increases, but it does not directly refer to random variation in population growth.
Option (D) refers to time lags in response to environmental changes but is unrelated to random variation in population dynamics.
Thus, (B) is the correct answer, as it directly addresses the random fluctuations in population size due to the discrete events of births and deaths.