CHAPTER 2 – PRINCIPLES OF ECOLOGY Section 2-1: Organisms and their Environment (p.35-45)

Sharing the World  Ecology will make you see the BIG PICTURE!!!!!  How much do you know about the environment and the organisms that share your life?  Understanding what affects the environment is important because it is where you live

What is Ecology?  The study of the interactions that take place between organisms and their environment  Ecological research includes many scientific fields + methods: Descriptive Descriptive Observing organismsObserving organisms Quantitative Quantitative Making measurements + performing experimentsMaking measurements + performing experiments

The Biosphere  Portion of Earth that supports living things From atmosphere to bottom of oceans From atmosphere to bottom of oceans Comparison to Apple Peel Comparison to Apple Peel Ecologist study how organisms survive and reproduce under different physical and biological conditions in Earth’s biosphere Ecologist study how organisms survive and reproduce under different physical and biological conditions in Earth’s biosphere

Abiotic Factors  Nonliving parts of an organism’s environment Examples: Examples: Air currentsAir currents TemperatureTemperature MoistureMoisture LightLight SoilSoil

Biotic Factors  All the organisms that inhabit an environment Example – Fish bowl Example – Fish bowl All organisms depend on others directly or indirectly for food, shelter, reproduction, or protection All organisms depend on others directly or indirectly for food, shelter, reproduction, or protection

Levels of Organization  Population Group of organisms, all of the same species, which interbreed and live in the same area at the same time Group of organisms, all of the same species, which interbreed and live in the same area at the same time Resources: Resources: SharingSharing CompetitingCompetiting Food Food Water Water Mates Mates Shelter Shelter

Biological community  Made up of interacting populations in a certain area at a certain time  A change in one population may cause change in other populations Example: Example: Hawk + MiceHawk + Mice

Ecosystem  Made up of interacting populations in a community, including the abiotic factors  May change due to biotic + abiotic factor changes

Types of Ecosystems  Terrestrial Located on land Located on land  Aquatic Freshwater Freshwater Ponds, lakes, + streamsPonds, lakes, + streams Saltwater Saltwater AKA - MarineAKA - Marine Ocean, tidal areasOcean, tidal areas

Organisms in Ecosystems  Habitat Place where an organism lives Place where an organism lives Examples:Examples: Lawn Lawn Bottom of stream Bottom of stream Beech-maple forest Beech-maple forest Can change due to natural + human causes; can even disappear Can change due to natural + human causes; can even disappear

Niche  All strategies + adaptations a species uses in its environment “Way of Life” “Way of Life” Includes all its interactions with biotic + abiotic factors Includes all its interactions with biotic + abiotic factors

Niche  Species survive longer if they occupy different niches  Organisms use different strategies to survive Examples: Examples: Polar Bear – thick fur coatPolar Bear – thick fur coat Hummingbird – long tongue to reach nectarHummingbird – long tongue to reach nectar  Unique adaptations reduce competition with other species in the same habitat

Symbiosis  The relationship in which there is a close and permanent association between organisms of different species  Means “living together”  3 types: Mutualism Mutualism Commensalism Commensalism Parasitism Parasitism

Mutualism  Relationship in which both species benefit from one another  Example: Ants + acacia tree Ants + acacia tree Cattle egret + buffalo Cattle egret + buffalo Shark + remora Shark + remora

Commensalism  Relationship in which one species benefits and the other is neither harmed nor benefited  Example: Spanish moss Spanish moss Clown fish + sea anemone Clown fish + sea anemone

Parasitism  Relationship in which a member of one species derives benefit at the expense of another species  Examples: Brown-headed cowbirds Brown-headed cowbirds Ticks Ticks Tapeworms Tapeworms Bacteria Bacteria

Predator-Prey  Predator Seek out and eat other organisms Seek out and eat other organisms  Prey Animal that predators eat Animal that predators eat  Examples: Hawk/snake Hawk/snake Bear/caribou Bear/caribou