2. Rules: You will be given an interaction between two living organisms. With your team quietly discuss what type of symbiosis you think it is: commensalism, parasitism, or mutualism. When time is up you will be ask to hold up your card to show what type you think it is. Each correct answer gets your team one point.

3. The gall wasp lays eggs in an oak tree, causing a lump that isn’t harmful to the tree. It also gets shelter and food from the tree

4. Commensalism

5. The cowbird eats pests and parasites off the back of the bison which in turn nourish the cowbird

6. Mutualism

7. The cowbird lays eggs in other birds’ nests and the cowbird chicks hatch early and are much larger than the host egg chicks. The cowbird either push out the host eggs or because of their aggressive nature over compete for food and the host chicks starve.

8. Parasitism

9. Morel mushrooms help the tree roots absorb water and minerals, and sugar and starches are absorbed by the mushroom. When the tree dies the mushroom produces spores to reproduce.

10. Mutualism

11. The monarch butterfly drinks nectar and lays eggs on milkweed. The monarch larvae eat the milkweed leaves and obtain the leaves’ poisonous chemical which prevents predators from eating them, the monarch also pollinates the milkweed.

12. Mutualism

13. Mosquitoes eat human blood for nutrition to lay eggs

14. Parasitism

15. Grape vines grow up the tree to get more light and space.

16. Commensalism, but some other vines kill the tree which is parasitism

17. Freshwater cyprinid fish deposit eggs in siphon tube of freshwater bitterling-mussels. Eggs develop in gill cavity, decreasing mussel growth.

18. Parasitism

19. The human digestive system contains bacteria which aide digestion and vitamin production, as well as bacteria that leads to disease and death.

20. Mutualism