Scientists use age structure to predict future growth patterns:They analyze factors such as:•Number and proportion of individuals in each age group.•The number of males versus the number of females in each age group.
Scientists use age structure diagrams to:1. Compare age groups such as pre-reproductive to reproductive ages2. Compare the number of males to the number of females
Scientists use the shape of the graph to determine:1. If a population is growing, shrinking or staying the same2. Growth momentum (how soon overpopulation will become a problem)
AGE STRUCTURE DIAGRAMS
The shape of the age structure diagram tells you:1. If a population is increasing, stable or shrinking2. Population growth momentum- even if people are having less children, the effect won’t take place until much later when the children reach reproductive maturity.
1. Expanding/growing population- pyramid shape, has more children than any other age group.- Nigeria or Bolivia2. Stable populations- Number of children is roughly the same as the number of reproductive adults- European countries3. Declining population- Pre-reproductive group is smaller- Russia, Bulgaria and Germany