scientists use age structure to predict future growth patterns: they analyze factors such as: number...

3
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 ages 2. 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 same 2. Growth momentum (how soon overpopulation will become a problem) AGE STRUCTURE DIAGRAMS

Upload: duane-ball

Post on 01-Jan-2016

215 views

Category:

Documents


1 download

TRANSCRIPT

Page 1: Scientists use age structure to predict future growth patterns: They analyze factors such as: Number and proportion of individuals in each age group. The

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

Page 2: Scientists use age structure to predict future growth patterns: They analyze factors such as: Number and proportion of individuals in each age group. The

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.

Page 3: Scientists use age structure to predict future growth patterns: They analyze factors such as: Number and proportion of individuals in each age group. The

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