ECOLOGY CHAPTERS 18-23 Study of the interactions between organisms & the living & non-living components of their environment.

Today’s Environment Ecological problems Exploding human population Mass Extinction Thinning ozone layer Climatic changes

Ecological Research Conducted using three basic principles: Observing Experimenting Modeling

Energy Flow Main energy source for life on earth Autotrophs SUN Autotrophs Make food by means of photosynthesis or chemosynthesis PRODUCERS Heterotrophs Rely on other organisms for food CONSUMERS

Types of Heterotrophs Herbivores: eat plants Carnivores: eat animals Omnivores: eat both (plants/animals) Detritovores: eat dead matter Ex. Earthworms Decomposers: break down organic matter Ex. Fungi

Food Chains & Food Webs Food Chain Food Web Shows how living things transfer energy by eating & being eaten Food Web Links all food chains in an ecosystem together Shows a network of complex interactions

Levels of Organization Description Biosphere Broadest, most inclusive level Thin volume of earth & its atmosphere that supports life Ecosystem Includes all living & non-living components found in a particular place Pond: fish, turtle, water, etc. Community All interacting organisms living in an area May contain thousands of species Population All members of a species that live in one place at one time Organism Simplest level of organization

Ecosystem Recycling The Water Cycle

Nitrogen Cycle

Carbon Cycle

Biosphere Cycles Click on diagram to play a video on Biosphere Cycles…

Ecology of Organisms Habitat Biotic Factors Abiotic Factors Where an organism lives Biotic Factors Living components of an environment Abiotic Factors Physical & chemical (non-living) characteristics of an environment Temperature, light, humidity, pH, salinity, O2 concentration, precipitation, etc Abiotic factors are not constant

Biomes Tropical Rain Forest Desert Tundra Taiga Grassland Savanna Temperate Deciduous Forest Chapparal

Biomes of the World

Tolerance Curve Graph of performance vs. values of an environmental variable, such as temp.

Terms Acclimation Conformers Regulators Dormancy Migration An organism’s ability to adjust their tolerance to abiotic factors, such as high elevation Conformers Do no regulate internal conditions Regulators Use energy to control some internal conditions Dormancy State of reduced activity Migration Movement to a more favorable environment

Niche A species’ way of life; the role it plays in its environment Fundamental Niche Range of conditions a species can potentially tolerate & range of resources it can potentially use Realized Niche Range of resources a species actually uses

Generalists vs. Specialists Species with a broad niche Virginia opossum (feeds on anything) Specialist Species with narrow niches Koala bear (eats only leaves of eucalyptus tree)

Community Ecology Symbiosis: Relationships among species Predation Predator kills & consumes prey Parasitism One organism benefits & other is harmed Competition Species compete for same resources Mutualism Cooperative relationship in which both species benefit Commensalism One organism benefits & the other is not affected

Succession The gradual, sequential regrowth of a species in an area. Primary succession Development of a community in an area that has not supported life previously, such as bare rock, sand dunes, or an island formed from volcanic eruption. Secondary succession Sequential replacement of species that follows disruption of an existing community. Pioneer species: species that predominate early in succession Climax community: Stable end point following succession

Environmental Science A field of science that uses biological principles to look at the relationships between humans & the earth.

Human Effects on Environment Declining ozone Greenhouse Effect CO2 Blanket; increase temperature Human Population Growth

Effect of Rising Population Burn more fossil fuels Less fresh drinking water Decrease in undeveloped land Extinction of many species Increase in human waste Less food More disease & death Potentially more natural disasters

Taking Action!! Conservation Biology An area of science which tries to identify & maintain natural areas Restoration Biology An attempt at saving a devastated area