How do organisms How do organisms interact?interact?

Lesson 4Lesson 4

competition• animals & plants may compete for:

1. Space

2. Water

3. Light

4. Food

5. Mates

Black bears will compete with each other for mates and

territory.

Sheep compete by hitting their horns together.

kudzu kudzu The Vine that Ate the South

mile-a-minute vine, foot-a-night vine

• prevents the plants it covers from getting sunlight

• The problem with kudzu is that it just grows too well!

• The climate of the Southeastern U.S. is perfect for kudzu.

• The vines grow as much as a foot per day during summer months, climbing trees, power poles, and anything else they contact.

• Under ideal conditions kudzu vines can grow sixty feet each year!!!

symbiosis

• long-term relationship between different species

• 1 species always helped• other might be :

– helped– harmed– or not affected at all

(commensalism)

parasite• organism that feeds off another organism

(called the host) & causes it harm

• ex: worms in buffalo’s intestines or bloodstream eat buffalo’s food & take oxygen from buffalo’s blood

lichen• Made up of a

fungus & a plant like bacteria or algae

• Both organisms benefit (mutualism)