Squirrel Lab
Problem: How does competition between native and invasive species affect population size?
Research:
Links: Red Squirrel -
Grey Squirrel -
Hypothesis: The population of red squirrels will decrease when the invasive more fit grey squirrels areintroduced into the ecosystem over time.
Research:
Links: Red Squirrel -
Grey Squirrel -
- http://en.wikipedia.org/wiki/Eastern_gray_squirrel
- http://www.about-squirrels.com/grey-squirrels.html
Hypothesis: The population of red squirrels will decrease when the invasive more fit grey squirrels areintroduced into the ecosystem over time.
Conclusion
Questions:
1. It was easiest for the red squirrels to collect resources before the grey squirrels came. It was hardest when the gray squirrels came because they were more fit. So they stole most of the resources.
2. Organisms in the same population will compete for resources when there are little to no resources available. This can happen if a drought occurred or if an invasive species invaded.
3. Usually the competition will reduce the amount of resources in an area. In this lab competition between squirrels caused the plants to dwindle in population.
4. The native squirrels niche would have to become the predator of grey squirrels or the predator of something else. Since the niche of both was herbivore then one would have to change to an omnivore or carnivore. They could also migrate to a new ecosystem.
CER:
Claim: The red squirrel population decreased when the grey squirrels invaded.
Evidence: The red squirrel, predator and resource populations were all doing fine until the invasive species invaded. Being more fit then the red squirrels they were able to throw the ecosystem off of equilibrium. As the graph above shows the red squirrel population decreased drastically after the grey squirrels invaded. The average for the red squirrel population for the second decade after the was thirty while for the grey squirrels was approximately 139. This is a huge difference in the population sizes.
Reasoning: The Red Squirrels and the Grey Squirrels share the same niche. Because of this there will be competition. When competition occurs then natural selection will also. The grey squirrels who are more fit will probably win. Then natural selection will either change the niche of the red squirrel or drive them to extinction.
1. It was easiest for the red squirrels to collect resources before the grey squirrels came. It was hardest when the gray squirrels came because they were more fit. So they stole most of the resources.
2. Organisms in the same population will compete for resources when there are little to no resources available. This can happen if a drought occurred or if an invasive species invaded.
3. Usually the competition will reduce the amount of resources in an area. In this lab competition between squirrels caused the plants to dwindle in population.
4. The native squirrels niche would have to become the predator of grey squirrels or the predator of something else. Since the niche of both was herbivore then one would have to change to an omnivore or carnivore. They could also migrate to a new ecosystem.
CER:
Claim: The red squirrel population decreased when the grey squirrels invaded.
Evidence: The red squirrel, predator and resource populations were all doing fine until the invasive species invaded. Being more fit then the red squirrels they were able to throw the ecosystem off of equilibrium. As the graph above shows the red squirrel population decreased drastically after the grey squirrels invaded. The average for the red squirrel population for the second decade after the was thirty while for the grey squirrels was approximately 139. This is a huge difference in the population sizes.
Reasoning: The Red Squirrels and the Grey Squirrels share the same niche. Because of this there will be competition. When competition occurs then natural selection will also. The grey squirrels who are more fit will probably win. Then natural selection will either change the niche of the red squirrel or drive them to extinction.