Principles of Ecology

Ecology

Symbiosis

• A relationship where there is a close and permanent association among organisms of different species

• Symbiosis means “living together”

Commensalism• A symbiotic relationship

where one species benefits and the other species is unaffected

• Example: Shark and a crab. The crab needs the shark to eat fish near the surface of the ocean so pieces of the dead fish fall to the ocean floor for the crab to eat. Crab benefits from the shark, shark is unaffected.

Mutualism• A symbiotic relationship

where two species mutually benefit (help) each other

• Example: Ants and the Acacia tree. Ants attack any animals that try to come and feed off the tree. The tree provides nectar and a home for the ants..

Parasitism

• A relationship in which one organisms benefits at the expense or harm of another organism

• Example: Fleas on a dog. The fleas drink the blood from the dog. The dog get bitten, itchy and if bad enough anemic from blood loss.

Predator/Prey

• Predator is an animal that eats another animal

• Prey is the animal being eaten by the predator

• This is a relationship that is good for one organism and the other ends up dead/eaten

• Example: Wolf and a rabbit.

Autotroph

• An organism that uses energy from the sun or energy from chemical compounds to make their own nutrients– Example: Plants do

photosynthesis and some organisms deep in the ocean do chemosynthesis

– https://www.youtube.com/watch?v=BLOUFrncG7E

Heterotroph

• An organism that must feed on other organisms– Some heterotrophs feed

on autotrophs (rabbit eating grass)

– Some heterotrophs feed on other heterotrophs (fox eating rabbit)

Producer

• A producer is an autotroph

• Examples:– Plants/flowers– Trees– Herbs– Grasses– Algae– Some plankton– Some bacteria

Consumer

• An organism that eats other organisms- Heterotroph

• Examples:– Frog eats bugs– Deer eats grass– Bear eats fish – Slug eats my garden– Human eating an egg

Scavenger

• Some animals do not kill their own food, instead they eat something that has already died

• A scavenger is an animal that feeds on animals that are already dead– Examples: buzzard,

vulture, insects, hyenas

Decomposers

• Organisms that break down, absorb and recycle nutrients from dead organisms

• They are important in keeping an ecosystem healthy– Examples: Fungi and

bacteria

Latin Names

• Herbivore- eats plants (rabbit, deer, caterpillar, giraffe)• Carnivore- eats animals (wolf, lion,

shark, anteater)• Omnivore- eats both plants and

animals (bear, human, monkey)

Food Chain

• A simple model that scientists use to show how matter and energy move through an ecosystem

Food Web• All of the possible feeding relationships at each trophic

level• Trophic Level: a step in the food chain or food web.