1. Ecology Introduction PG. 100

2.  Ecology = scientific study of interactions between organisms, and between organisms and their environment –Biosphere = all parts of our earth where life exists  Life depends on interactions between living and non-living parts of the biosphere

3. 6 Levels of Organization 1. Biome Group of ecosystems with the same climate and similar dominant communities (desert, tundra, taiga, temperate forest, tropical rainforest, artic) 2. Ecosystem Collection of all organisms that live in a particular place, together with the non-living parts of their environment 3. Communities Assemblies of different populations living in a defined area 4. Populations Groups of individuals belonging to the same species and living in the same area 5. Species Group of organisms so similar to one another they can breed and produce fertile offspring 6. Individual One member of a species

4. 6 Levels of Organization Biome Ecosystem Community Population Species Individual

5. Parts of an Ecosystem  Biotic factors = living, biological, factors that shape ecosystems –Trees, mushrooms, bacteria, animals, flowers, etc.  Abiotic factors = physical or non-living factors that shape ecosystems –Rocks, water, soil, air, sunlight  Biotic + Abiotic factors determine the survival and growth of an organism and the productivity of the ecosystem Abiotic factors Biotic factors

6. Who Lives in an Ecosystem  Habitat = an organism’s address, where it lives  Niche = an organism’s occupation, what it does in its habitat –Includes:  Where it fits into the food web  Type of food it eats  How it obtains food  When and how it reproduces  No 2 species can share the SAME habitat and the SAME niche  But, different species can occupy similar niches in the same habitat

7. Biomes  Earth is divided into 10 biomes  Biome = a complex of terrestrial communities covering a large area, characterized by a certain type of soil and climate, and contains particular types of plants and animals

8. Energy Flow  Everything needs energy  The Sun is the ultimate source of energy  Energy flows through an ecosystem  Producers = obtain energy directly from the sun or capture energy from chemicals –Autotrophs = plants, some algae, and certain bacteria can capture the sun’s energy or use chemicals to produce their own food –Autotrophs are producers

9. Consumers  Consumers = organism that feeds on other plants and animals –Heterotrophs = organisms that rely on other organisms for their energy and food supply –Consumers are heterotrophs  Types of heterotrophs: –Herbivore – eats only plants –Carnivore- eats only animals –Omnivore- eats plants and animals –Detritivore – eats plant and animal remains, dead things –Decomposers – breaks down organic matter cow, sheep, caterpillar snakes, dogs, owls humans, bears, crows mites, earthwor ms, snails, crabs bacteria, fungi