the way that characteristics become common in a species

• adaptation
• natural selection
• niche

A behavior or physical characteristic that helps an organism live in an environment

• adaptation
• natural selection
• niche

the way an organism makes a living

• adaptation
• natural selection
• niche

the struggle between organisms to stay alive

• competition
• predator
• predation 

when one organism kills another for food: IE Hawk killing a rat

• competition
• predator
• predation

THE organism that kills another organism
IE: HAWK

• competition
• predator
• predation

an organism that is killed and eaten:  IE the rat

• mutualism
• prey
• symbiosis

a close relationship between two species

• mutualism
• prey
• symbiosis

when both species help each other

• mutualism
• prey
• symbiosis

when one species is helped and the other species is not harmed

• commensalism
• parasitism