EcologyEcology

EcologyEcology

Ecology is the study of Ecology is the study of interactions between interactions between different kinds of living different kinds of living things and their things and their environment.environment.

Why is Ecology Important?Why is Ecology Important?

Why care about Why care about ecology?ecology?•Ecological research Ecological research provides us with the provides us with the necessary info. to necessary info. to resolve many of the resolve many of the environmental problems environmental problems that surround us.that surround us.

•We are dependent We are dependent upon the world’s upon the world’s ecosystems, therefore, ecosystems, therefore, we must learn how to we must learn how to keep the environment keep the environment safe for all living safe for all living organisms.organisms.

BiosphereBiosphere•The portion of Earth that The portion of Earth that supports lifesupports life

•Several kilometers below Several kilometers below ocean’s surface and several ocean’s surface and several kilometers into the kilometers into the atmosphereatmosphere

Biotic FactorsBiotic Factors

•Living things with which Living things with which an organism interactsan organism interacts

•Animals, plants, fungi, & Animals, plants, fungi, & microorganismsmicroorganisms

Abiotic FactorsAbiotic Factors

•Nonliving factors in an Nonliving factors in an organism’s environmentorganism’s environment

•Temperature, rainfall, sunlightTemperature, rainfall, sunlight

•Air or water currentsAir or water currents

•Type & acidity of soilType & acidity of soil

•Availability of nutrientsAvailability of nutrients

PopulationPopulation•A group of a single species A group of a single species that lives in a given area at that lives in a given area at the same timethe same time

•Ex: school of fishEx: school of fish•Compete for same Compete for same resourcesresources

Biological Biological CommunityCommunity

•A group of interacting A group of interacting populations that populations that occupy the same occupy the same geographic area at geographic area at the same timethe same time

EcosystemEcosystem

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

BiomeBiome•A large group of A large group of ecosystems that share ecosystems that share the same climate and the same climate and have similar types of have similar types of communitiescommunities

•We’ll cover more in Ch. 3

HabitatHabitat•An area where an An area where an organism lives.organism lives.

•Ex: Tree or a grove of Ex: Tree or a grove of treestrees

NicheNiche•The role or position that The role or position that an organisms has in its an organisms has in its environmentenvironment

•How the organism meets How the organism meets its needs for food, shelter its needs for food, shelter and reproduction.and reproduction.

PredationPredation

•One organism consuming One organism consuming another organism for foodanother organism for food

•Predator eats the preyPredator eats the prey

•Ex: Cougar eats a rabbitEx: Cougar eats a rabbit

Symbiotic Symbiotic RelationshipsRelationships

•Symbiosis - Close relationship Symbiosis - Close relationship that exists when two or more that exists when two or more species live togetherspecies live together

•Mutualism, Commensalism, Mutualism, Commensalism, ParasitismParasitism

MutualismMutualism•Both organisms benefitBoth organisms benefit

•Ex: Lichens - between Ex: Lichens - between fungi and algaefungi and algae–Algae provides food for Algae provides food for fungi and fungi provide fungi and fungi provide a habitat for the algaea habitat for the algae

CommensalismCommensalism•One organism benefits, the One organism benefits, the other is neither helped nor other is neither helped nor harmedharmed

•Ex: Clownfish and sea Ex: Clownfish and sea anemonesanemones– sea anemones protect & provide food sea anemones protect & provide food

for the clownfishfor the clownfish– clownfish neither benefits nor harms clownfish neither benefits nor harms

the sea anemonesthe sea anemones

ParasitismParasitism•One organism benefits at One organism benefits at the expense of anotherthe expense of another

•Ex: Dogs & heartworms, Ex: Dogs & heartworms, ticks, fleas, tapewormsticks, fleas, tapeworms

•Do not always kill the Do not always kill the host - harm ithost - harm it

Energy in an EcosystemEnergy in an Ecosystem

•Plants are Plants are primary primary producersproducers

•Producers are also called Producers are also called autotrophsautotrophs (self-feeding) (self-feeding)–Produces its own food by Produces its own food by collecting energy from collecting energy from sunlight or inorganic sunlight or inorganic substancessubstances

ConsumersConsumers•ConsumersConsumers cannot collect energy cannot collect energy

directly from the sundirectly from the sun•ConsumersConsumers must eat other must eat other

organisms in order to obtain energyorganisms in order to obtain energy•Animals and bacteria are Animals and bacteria are

consumersconsumers•Animals are also called Animals are also called

heterotrophicheterotrophic because they must because they must feed on other organisms to obtain feed on other organisms to obtain energyenergy

HeterotrophsHeterotrophs•Must consume other Must consume other organisms to get its energyorganisms to get its energy– HerbivoresHerbivores– CarnivoresCarnivores– OmnivoresOmnivores– ParasitesParasites– DecomposersDecomposers– DetritivoresDetritivores

HerbivoresHerbivores

•Herbivores obtain Herbivores obtain energy by eating energy by eating autotrophs (plants)autotrophs (plants)

• = Primary (1= Primary (1oo) ) consumersconsumers

CarnivoresCarnivores

•Carnivores obtain energy Carnivores obtain energy by eating other animalsby eating other animals

•Secondary (2Secondary (2oo) or ) or Tertiary (3Tertiary (3oo) consumers) consumers– heterotrophs that prey on other heterotrophs that prey on other

heterotrophsheterotrophs

OmnivoresOmnivores

•Omnivores are Omnivores are animals that eat both animals that eat both plants and animalsplants and animals

DetritivoresDetritivores•Eats fragments of dead matter in an Eats fragments of dead matter in an ecosystem, and returns nutrients to the ecosystem, and returns nutrients to the environmentenvironment

•Ex: worms, aquatic insects on stream bottomsEx: worms, aquatic insects on stream bottoms

DecomposersDecomposers

•Decomposers break Decomposers break down dead organisms down dead organisms by releasing digestive by releasing digestive enzymesenzymes

•Ex: Fungi & bacteriaEx: Fungi & bacteria

Energy FlowEnergy Flow

•The source of energy (for The source of energy (for most ecosystems) is the most ecosystems) is the sunsun

•Energy and nutrients are Energy and nutrients are passed from organism to passed from organism to organism through the organism through the food chainfood chain

•Ultimately, energy will Ultimately, energy will be LOST as HEATbe LOST as HEAT–It does not continuously It does not continuously cyclecycle

–Black arrowsBlack arrows

•Nutrients, however, Nutrients, however, continuously CYCLE through continuously CYCLE through food webs and through the food webs and through the geological world.geological world.–White arrowsWhite arrows

Trophic LevelsTrophic Levels

•Feeding level in the flow of Feeding level in the flow of food energy from producers food energy from producers to the highest level of to the highest level of consumersconsumers–Primary (1Primary (1oo), secondary (2), secondary (2oo) ) & tertiary (3& tertiary (3oo) consumers) consumers

•See ecological pyramids on p. 44See ecological pyramids on p. 44

•Only 10% of the energy Only 10% of the energy in one trophic level is in one trophic level is passed on to the next passed on to the next levellevel

–The rest is used by the The rest is used by the organism or lost as heatorganism or lost as heat

BIOMASSBIOMASS• Biomass - combined mass of Biomass - combined mass of

all the organisms in that all the organisms in that trophic leveltrophic level

• As the trophic level increases, As the trophic level increases, biomass decreases biomass decreases

1.1. not everything in the lower levels gets eaten not everything in the lower levels gets eaten

2.2. not everything that is eaten is digested not everything that is eaten is digested

3.3. energy is always being lost as heat energy is always being lost as heat

Food ChainFood Chain•A simple, straight-line A simple, straight-line sequence of organisms sequence of organisms consuming other consuming other organismsorganisms

•Grass Grass grasshopper grasshopper mouse mouse hawk hawk

Food WebFood Web

•Complex feeding Complex feeding relationships that result relationships that result from interconnecting from interconnecting food chainsfood chains

•See p.43See p.43

ReviewReview

•What factors are included in What factors are included in an ecosystem that are not an ecosystem that are not included in a community?included in a community?

•Describe how ecosystems and Describe how ecosystems and biomes differ.biomes differ.

•How is a habitat different How is a habitat different from a niche? Example?from a niche? Example?

•Compare/contrast food chains Compare/contrast food chains and food webs.and food webs.