Ecology

• The relationship among organisms and their environment

Biosphere

• The portion of the earth that supports life. The earth and it’s atmosphere.

Biotic Factors

• The living factors in an organism’s environment.

• Ex: all of the frogs, fish, algae, etc. that reside in a pond.

Abiotic Factors

• The nonliving factors in an organism’s environment.

• Ex: temp., pH, air or water currents, sunlight, soil type, nutrients available in the soil, amount of precipitation

Levels of Organization in Ecology

Biosphere Biome Ecosystem Community Population Organism

Population

• Organisms of a single species that share the same location at the same time.

• Ex: deer population in a forest, all of the fish in a pond

Community

• Group of interacting populations that occupy the same area at the same time.

• Ex: all of the fish, algae, turtles, bacteria, frogs, etc. in a pond.

Ecosystem

• A biological community and all of the abiotic factors that affect it.

• Ex: all of the organisms in a pond and the soil, water, precipitation, etc.

Biome

• Large group of ecosystems that share the same climate and have similar types of communities.

• Ex: Desert, tropical rainforest

Ecosystem Interactions

• Habitat = an area where an organism lives

• Ex: animal residing in hollow log

• Niche = role a species plays in it’s environment

Community Interactions

Competition

• Occurs when more than one organism uses a resource at the same time.

• Ex: competition for food & water

Predation

• The act of one organism consuming another organism for food.

• Predator = organism that pursues other organism

• Prey = organism that is pursued

• Ex: cat and mouse, Venus fly trap & insects

Symbiotic Relationships

• The close relationship that exists when two or more species live together.

• Three types: mutualism, commensalism, and parasitism.

Mutualism

• The relationship where both species benefit.

• Ex: Lichens (algae & fungus). Algae provides food for fungus, fungus provides habitat for algae. Ex: Pollination. Pollinators = animals that carry pollen = bees, butterflies, bats, birds.

Commensalism

• Relationship in which one organism benefits and the other is not affected.

• Ex: clownfish & sea anemone, Spanish moss/oak tree. Spanish moss (flowering plant) grows in oak tree’s branches (habitat).

Parasitism

• One organism benefits/one harmed

• External Parasites (Ectoparasites): fleas, ticks, etc.

• Internal Parasites (Endoparasites): Tapeworms, Roundworms