Population pyramids

Today in honors human geo we started our discussion of population pyramids.  Population pyramids are graphs that are turned on their side, and they show the amount men and women in each 5 year increment that live in a population.  These population pyramids are split into 3 parts. Pre-reproductive years(0-14),reproductive years(15-45),and post-reproductive years (45-100+).  We watched a TED Ed video that explained these graphs.  We looked at three main examples.  One of these examples was a developing pre-industrial African nation.  This graph was pyramid shaped, with the most amount of pre-reproductive years, and the least in the post reproductive years.  This shape of pop. Pyramid shows that the population of a country is supposed to grow because there are many people in their reproductive years,and about to reach their reproductive years.  Another type of graph was one where it is almost flat down the sides, but narrower on the bottom.  This configuration of graph shows that the population is supposed to grow slowly.  This is because there are less people moving towards,or in their child baring years.  The final configuration of pop..pyramid that we looked at was a graph in which the bottom is narrower than the top. This means that the population is aging, less people are born, and the population should be decreasing.