Lessly Model Population Growth and Decay

Terms Ages – This is the ages of the animal broken into equal parts. Birth Rate – This is the rate at which babies are born at each age group. Survival Rate – This is the rate at each age group that determines how many animal survive to the next age group

Example Ages in years Birth Rate Survival Rate This means that this animal will live to an age of 15 years old at most. Also when they are 0-3 years old they do not have children

Example Ages Birth Rate Survival RatePopulation How many of the 0-3 year olds will survive to become 3-6 year olds? A survival rate of.7 and an age group population of 20 means that.7 x 20 =14

Example Ages Birth Rate Survival RatePop. 3 years later x 20.8 x 30.9 x 20.6 x 10

To Find the Number of babies First realize the babies born over a 3 year period of time will all be between 0 and 3 years old. Since each age group has a different population and a different birth rate you will have to calculate each separately and then add them together.

Example Ages Birth Rate Survival RatePop. 3 years later x x x x x 5 = 33

Now Find the Number of Animals in Each Age Group 3 Years Later. 3 more years will be 6 years from the beginning. Follow the same steps as before but use the 3years later column to generate the populations. Even though you can’t have a part of an animal keep the decimals do not round. Do this on your own before checking it

Example 2 Ages Birth Rate Survival RatePop. 3 years latter 6 years later

Example 2 Ages Birth Rate Survival RatePop. 3 years latter 6 years later