Community interactions

What’s a community? All the living things in an area Habitat: the place an animal lives Niche: an animal’s job, or function in the community What plants and animals live in an oak woodland community?

Rolls in a community Producers: The organisms that can make food blue-green bacteria, plants Consumers: organisms that must eat other organisms Animals Decomposers: Get their energy by breaking down dead matter bacteria, fungi, worms

Relationships in a community Many different relationships are found between organisms in every community predator/ prey Symbiosis Mutualism Commensalisms Parasitism

Predation One organism eats another The one being eaten always dies The predator benefits the prey does not +/- Ladybug beetle preying on an aphid. (Source: Photo by Graham Shepard, Rothamsted Research)

Symbiosis Any relationship in which two species live closely together One example is lichen: algae & fungus live as one

Mutualism a symbiotic relationship in which both species benefit cleaner fish & moray eel +/+

Commensalisms Relationship where one organism benefits & the other is neither harmed nor helped. epiphytes and their host trees, +/ 0

Parasitism One organism lives at the expense of another The parasite is helped, the host is harmed +/- Tapeworm life cycle

Review What kind of relationship is it when both organisms benefit? What is it called when one organism benefits and the other is not effected? What is this picture an example of?