This document defines and describes different types of population pyramids, including stable, stationary, expansive, and constrictive pyramids. It explains that population pyramids illustrate the breakdown of a population according to age and sex, and can be used to interpret dynamics like fertility and mortality rates of a country or city.

1. By Garret Taylor
5th period
Mrs.Morton

2.  Population pyramid-a diagram in the form of a
pyramid that illustrates the breakdown of
population according to age and sex.

3.  It shows the percent of intervals of certain ages
for each sex in millions for certain countries or
cities.

4.  The population of the age intervals make the
shape of the pyramid.

5.  Stable pyramid-A population pyramid showing an
unchanging pattern of fertility and mortality.
 Stationary pyramid-A population pyramid typical of
countries with low fertility and low mortality, very
similar to a constrictive pyramid.
 Expansive pyramid-A population pyramid that is very
wide at the base, indicating high birth and death rates.
 Constrictive pyramid-A population pyramid that
comes in at the bottom. The population is generally
older on average, as the country has long life
expectancy, a low death rate, but also a low birth rate.

6.  They are used for the fertility and mortality
rates of a country/city.
 A geographer uses population pyramids as a
blueprint to interpret the dynamics of a
population.

7.  A pyramid with steep sides and a wide base
indicates a country with high birth rates and
low life expectancy. For example, similar to
many developing countries, Pakistan has high
birth rates and low life expectancy.