1. Community Interactions

2. Competition
Organisms fight to survive

3. Predator/Prey Predator hunts. Prey is being hunted.
We will further investigate this idea later…

4. Symbiosis
organisms that interact and live closely together

5. 3 types Mutualism Example Both organisms benefit
Bacteria in your intestines
They get food
You get the cellulose digested so you can eat plants

6. Parasitism One is harmed and one is helped Examples
Tick on a dog’s ear
The tick gets food (blood)
The dog loses blood, gets a sore, and can get diseases

7. Commensalism One benefits and one is neither harmed nor helped
Example:
Clown fish and anemones
The clown fish gets protection from predators
The anemone gets nothing

8. Guided practice
Can you think of examples of commensalism in human relationships?

9. Assessment Which situation best represents a mutualistic relationship?
A A tapeworm absorbing nutrients from the intestine of a dog
B An orchid being pollinated by a nectar collecting wasp
C A human losing blood to a feeding mosquito
D An armadillo rooting in the soil at the base of an oak tree

10. Answer
B – The orchid is pollinated (and can therefore reproduce), and the wasp gets nectar for food.
All of the other answers describe parasitic relationships