Final answer:
During the Transitional stage (Stage 2) of the Demographic Transition Model, death rates fall rapidly while birth rates remain high, leading to a significant increase in population growth. Later stages show stabilization and potential decline in population.
Step-by-step explanation:
The Transitional stage or Stage 2 of the Demographic Transition Model (DTM) is characterized by a dramatic fall in death rates due to improvements in healthcare, sanitation, and nutrition, with birth rates remaining high. This discrepancy between the falling death rate and the still high birth rate leads to a surge in the population growth rate. This phenomenon can be attributed to the lag time in adjustments to family planning and cultural practices that result in continued high fertility rates despite lower mortality. As a country continues to develop, this rapid population growth poses challenges in terms of providing resources for the growing population.
Eventually, as a country progresses through the DTM, it may reach Stage 4, where both birth and death rates are low, stabilizing the population growth. Some nations might even enter a proposed Stage 5, characterized by very low birth rates, potentially lower than the death rates, causing natural population decrease. This stage is evident in countries like Japan and parts of Europe, whereas the United States is slowly transitioning towards it.