The situation described where a population's birth rate equals its death rate implies that the number of individuals being born is equal to the number being deceased over a defined time period. This balance results in no net change in the total population size.
Let's break it down step-by-step:
1. Birth Rate: This refers to the number of births occurring in a population per unit of time, such as a year.
2. Death Rate: This refers to the number of deaths occurring in a population per unit of time, such as a year.
3. Equal Birth and Death Rates: When the birth rate equals the death rate, the additions to the population (via births) are exactly offset by the reductions in the population (via deaths).
Thus, the net effect is that the population size remains constant, indicating zero population growth.
Given the options:
A. low
B. zero
C. high
D. moderate
B. zero is the correct answer.
So, when a population's birth rate equals its death rate, there is zero population growth.
