2. Chocolati Chipus - a population study

3. Remember…
A population is a group of organisms of the same species living in the same area.

4. Four things affect population size:
Deaths: organisms dying
Births: organisms being born
Emigration: organisms leaving
Immigration: organisms moving in

5. Graphing Population Over Time
The species Chocolati chipus (called “chips” for short) lives in the forests of the North. It eats mostly small insects. The chips’ main predators in the area are rats.
Keep track of what happens to one chipus population by graphing the population size over a time period of 10 years.
The population will start with 100 individuals. (Each chip represents 10 individuals)

6. Directions
Follow the population of chipus over ten years on your graph
If members of the population are killed or leave, you must remove them from your environment (you can eat them).

7. Graph Label and number the axis of your graph
We will start with 100 chipus (Year 0), and follow the chipus until year 10.
The population size will not get larger than 200 chocolati chipus during our study.

8. Year 1
The rat population in the area increases, so fifty members of the Chocolati chipus population are eaten by rats. Thirty baby chips are born this year.

9. Year 2
The rat population in the area is even bigger, so this year sixty chips are eaten. Thirty baby chips are born this year.

10. Year 3
Some of the rats are starting to starve, but the rat population is still large. Forty chips are eaten. Thirty baby chips are born this year. Also, thirty chips from a population nearby immigrate.

11. Year 4
Many rats starved the year before, so now the rat population is low. Only twenty chips are eaten this year. There is lots of food available, so seventy babies are born this year.

12. Year 5
The rat population is still small and there are still many insects available for food. Only ten chips are eaten this year and sixty baby chips are born.

13. Year 6
The chip population has gotten so large that it has eaten a large number of the insects in the area. Some chips have started starving. Forty chips died of starvation this year, but thirty baby chips were born.

14. Year 7
This year forty chips die of starvation, ten chips are eaten and only twenty babies are born.

15. Year 8
This year, thirty chips looking for new sources of food end up emigrating. Twenty baby chips are born this year and ten chips are eaten.

16. Year 9
This year no chips die of starvation or emigrate, but forty chips are killed by rats and thirty baby chips are born.

17. Year 10
Forty new baby chips are born this year and fifty chips are eaten by rats.

18. Year 11

19. Now… With your group, wrap your Chocolati Chipus sheet Finished?
Human Population Graphing - Due Wednesday