Ecological Interactions

Unit 6-1 NotesMr. Hefti – Pulaski Biology

Mutualism• Both species benefit• “+ +” relationship• Examples–Ants protect aphids that

provide them food–Clown fish / sea anemones

Predation

• Predator – hunter• Prey – hunted• “+ -”• Examples–Wolf hunts rabbits–Bear / salmon

Parasitism• Organism lives on or near another

causing harm• Host provides resources to parasite• “+ -”• Examples–Fleas / larger mammals–Tapeworms in intestines of large

mammals

Competition

• Organisms use same resources• “+ -”• Examples–Birds feeding on same foods–Mountain goats attracting mates

Commensalism

• One benefits / other not affected• “+ 0” • Examples–Orchids living on trees in

tropical forests–Barnacles on whales

See if you can identify the ecological

interactions and the +, -, or 0 relationships

shown in the following pictures…

1

2

3

4

5

Answers

• 1 – Parasitism (+-)• 2 – Mutualism (++)• 3 – Competition (+-)• 4 – Commensalism (+0)• 5 – Predation (+-)