Question

Why has the human population increased over the past 300 years even though the birth rate has remained about the same?

Answer 1

This rapid growth increase was mainly caused by a decreasing death rate (more rapidly than birth rate), and particularly an increase in average human age.

Answer 2

First, birth and death rates are both high, so little growth occurs. Second, death rates fall due to improved living conditions, while birth rates remain high. During this period population grows rapidly.