Final answer:
The tendency of a population to shift from high birth and death rates to low birth and death rates is called demographic transition. This transition occurs as a country develops and goes through different stages of population growth.
Step-by-step explanation:
The tendency of a population to shift from high birth and death rates to low birth and death rates is called demographic transition. This refers to the process in which an undeveloped country initially has high birth and death rates, but as medical and resource conditions improve, the death rate falls followed by a decline in the birth rate. This transition occurs as the country goes through different stages, moving from high population growth to a stabilized population.