Question

In change in population size $N_t=N_0+B+I-D-E$. I, B, D stands for rates of

• A. Immigration, mortality, natality
• B. Immigration, natality, mortality
• C. Emigration, natality, mortality
• D. Mortality, natality, immigration
• E. Mortality, immigration, natality

Answer 1

The correct option is B Immigration, natality, mortality

Population growth is defined as the increase in the number of individuals in a population. The rate of population growth is expressed by the number of individuals added per unit population in a specified time. Population growth rate actually measures how fast a population is changing. In general, there are some factors that contribute to the change in the size of a population, from a one-time step to the next. Some of these factors determine the increase in population size, which are births and immigration. Whereas, the other factors lead to a decrease in population size, which are deaths and emigration. If N₀ is the initial size of a population and N_t is its size after a specified time interval, then the following general equation helps to predict the population size at a future time.

N_t = N₀ + B + I - D − E

Here, within a specified time interval, B stands for natality rate, D is the mortality rate, I stands for immigration rate, and E equals the emigration rate.