3.5 Population Trends Quiz

Explanation
Scientists predict population sizes by using age structure, survivorship, and fertility rates. Age structure refers to the distribution of individuals in different age groups within a population, which helps determine the potential for future growth or decline. Survivorship refers to the probability of individuals surviving to different ages, which helps estimate how long individuals are likely to live and contribute to the population. Fertility rates measure the average number of offspring produced by individuals, which helps determine the rate at which new individuals are added to the population. By analyzing these factors, scientists can make predictions about future population sizes.

Explanation
Age structure diagram B shows a country experiencing rapid population growth. This is indicated by the large number of young individuals in the population pyramid, representing a high birth rate. The diagram also shows a narrower top, indicating a lower proportion of elderly individuals, which is characteristic of a country with a high population growth rate.

Explanation
Countries experiencing negative population growth are most likely to have a lower percentage of children than adults because negative population growth indicates that the number of deaths and emigration are higher than the number of births and immigration. This leads to a decrease in the overall population, and since children make up a significant portion of the population, their percentage would be lower compared to adults.

Explanation
Wealthy countries like Germany and Japan tend to have Type I survivorship because most people in these countries live to be very old. Type I survivorship is characterized by a low death rate at early and middle ages, with a high probability of surviving to old age. This is often seen in developed countries with advanced healthcare systems, high living standards, and access to quality healthcare services, which contribute to increased life expectancy and lower mortality rates.

Explanation
The graph shows that the fertility rate in Niger is higher than in the United States. This means that women in Niger have more children on average than women in the United States.