ECOLOGY

The Study of the Interaction of organisms with their environment

The Environment

• Biotic Factors all of the living things in the environment

• Abiotic Factors all of the nonliving things in the environment

Community

• All of the living things in an area that DEPEND on each other

Relationships in a Community -1

Symbiosis = “Living Together”– Close relationship between two or

more species– Examples

• Mutualism• Commensalism• Parasitism

Mutualism

• Both species benefit from the relationship

• WIN – WIN

• EX: acacia tree and ants.

Commensalism

• One species benefits from the relationship and the other is unaffected.

• WIN – “I don’t care”

• EX: Orchid

Parasitism• One species benefits (parasite)

and the other is harmed (host)

• WIN – LOSE

• EX: Tick

• Parasite does not want to kill the host. Why?

Relationships in a Community - 2

• Predation - The feeding of one organisms on another–Predator

• hunts/eats–Prey

• gets eaten

Habitat

• The Place where an organism lives

Niche

• The JOB of an organism in a community

Niches in a Community

• PRODUCER

• CONSUMER

• DECOMPOSER

Producer (Autotroph)

• Plants make food in a community

• Photosynthesis– using sunlight

to make food

Consumer (Heterotroph)

• Can’t make their own food

• Primary Consumer Eats plants

• Secondary Consumer Eats other animals

Decomposers• Are consumers

• Get food by breaking down dead matter

• Recycle nutrients

• Examples– Fungi (molds, mushrooms)– Bacteria

Energy

• The ability to do work

• Flows through an ecosystem

• What is the primary source of energy in an ecosystem? The

Sun

Food Chain

• Pathway of energy through an ecosystem

Sun GrassProducer

Grasshopper Primary

Consumer

BirdSecondaryConsumer

Food Web

• Food chains connected in a community

• All of the possible feeding relationships

Food Web

Energy Pyramid

PRODUCER

PRIMARY CONSUMER

SECONDARY CONSUMER

TERTIARY CONSUMER

Energy Pyramid• Shows energy loss in a

food chain– 90% lost as heat

• # of organisms at each level decreases– Less energy available

• Because of energy loss, maximum of 5 levels.