PRINCIPLES OF ECOLOGY Chapter 2

Organisms & Their Environment Ch. 2, Sec. 1

What is Ecology? Ecology = study of interactions between organisms & their environment

Disruptions to the environment can ripple throughout the entire ecosystem

Biosphere Biosphere = parts of Earth and its atmosphere that support life, from the sky down to the bottom of the ocean

Biotic Factors = the living parts of an ecosystem Abiotic Factors = the nonliving parts of an ecosystem (sun, temperature, pH, gasses, water) that are part of an organism’s life

Levels of Organization 1. Biosphere

2. Ecosystem = the biotic & abiotic parts of an environment found in a particular place The biosphere is made up of many different ecosystems

3. Communities = all the interacting living organisms in an area, all the different species

4. Populations = all members of the same species living in one place, at one time

5. Organism = the individual organism

Organisms in Ecosystems Habitat = the place where an organism lives out its life Niche = all strategies & adaptations a species uses in its environment; an species’ role What food they eat What kind of shelter used Where they reproduce

Having a specific role in an environment helps reduce competition

Survival Relationships (2 kinds) A. Symbiosis = organisms living closely together; 3 types of symbiosis

1. Mutualism = 2 species of organisms benefit from each other

2. Commensalism = one species benefits & the other is neither harmed nor benefited

3. Parasitism = one species benefits at the expense of another species

B. Predation = a predator eats another organism for food

http://www. cstephenmurray http://www.cstephenmurray.com/onlinequizes/biology/Ecology/typesofinteractionsexamples.htm

Practice Cowbirds lay their eggs in the nests of other birds and allow them to raise their chick usually at the expense of the offspring of the other species. What would happen to a forest community if the cowbird population increased?