ECOLOGY - Citrus Collegecitruscollege.edu/.../biology/Documents/GoodmanNotes/ECOLOGY.pdf · Ecology • The scientific ... Ecosystem • Dynamic system of organisms interacting with

CommunityCommunityEcologyEcology

EcologyEcology

• The scientific study of the interactionsinteractionsbetween organismsorganisms and their environmentsenvironments(abiotic and biotic).(abiotic and biotic).

1.1. Abiotic:Abiotic: nonnon--living factorsliving factors(temperature, light, water, and nutrients)

2.2. Biotic:Biotic: living factorsliving factors(other plants and animals)

Hierarchy of OrganizationHierarchy of Organization•• Biological organization:Biological organization:

Based on structural levelsstructural levels from LeastLeast to Most InclusiveMost Inclusive.

1. 1. AtomsAtoms2. 2. MoleculesMolecules3. 3. OrganellesOrganelles4. 4. CellsCells5. 5. TissuesTissues6. 6. OrgansOrgans7. 7. organs systems organs systems →→ The Realm Of EcologyThe Realm Of Ecology

8. Organisms8. Organisms

•• IndividualsIndividuals (species) composed of many specialized cells.

9. Populations9. Populations

•• LocalizedLocalized groupsgroups of organismsorganisms belonging to the same speciesspecies.

•• GroupsGroups of individualsindividuals of the same species living together.

10. Community10. Community

•• PopulationsPopulations of organisms living together in the same environment.

•• Four properties:Four properties:1.1. DiversityDiversity2.2. Prevalent form of vegetationPrevalent form of vegetation3.3. Stability (resist change)Stability (resist change)4.4. Trophic structure (feeding structure)Trophic structure (feeding structure)

11. Ecosystem11. Ecosystem

• Dynamic system of organisms interactinginteractingwith each other (biotic)(biotic) and the inanimate environment (abiotic).(abiotic).

12. Biomes12. Biomes

•• Broad geographic regionBroad geographic region with a characteristic array of organisms.

•• Examples:Examples:1.1. Tropical rain forestTropical rain forest2.2. DesertDesert3.3. ChaparralChaparral4.4. EstuariesEstuaries5.5. Coral reefsCoral reefs

13. Biosphere13. Biosphere

• Entire surface of the earthearth and its organismsorganisms.

HabitatHabitat

• The placeplace or regionregion where an organism lives.

Ecological NicheEcological Niche

• An organismsorganisms habitathabitat, , rolerole, , resource resource requirementsrequirements, , and tolerance rangestolerance ranges for eachabioticabiotic condition..

CompetitionCompetition

• A form of interactioninteraction in which two or more individuals or species utilize the same limited limited resourcesresources.

•• Two examples:Two examples:1.1. Intraspecific competitionIntraspecific competition

2.2. Interspecific competitionInterspecific competition

1. Intraspecific Competition1. Intraspecific Competition

•• CompetitionCompetition within a specieswithin a species for the same limited resourceslimited resources in the same habitat.

2. Interspecific Competition2. Interspecific Competition

•• CompetitionCompetition between two or more speciesbetween two or more speciesfor the same limited resourceslimited resources in the same habitat.

Competitive Exclusion PrincipleCompetitive Exclusion Principle

•• States the following:States the following:1.The concept that two speciestwo species cannot continue to

occupy the same environmental niche.

2.They would compete for the same limited resources.

3.One species will use the resources more efficiently and have a reproductive advantagethat will eventually lead to elimination of the other species.

SymbiosisSymbiosis

• A form of interspecific interactioninterspecific interaction in which a host specieshost species and symbiontsymbiont maintain a close association.

•• Example:Example:1.1. PredationPredation

1.1. PredationPredation

• Where one organism (the predator)(the predator) acquires its needed resources by eating another organism (the prey).(the prey).

•• Predator/prey relationship.Predator/prey relationship.

•• Example: Example: lynxlynx and snowshoesnowshoe hare

Question:Question:

• How do some organismsorganisms avoidavoid becoming preyprey?

•• Answers:Answers:1.1. CamouflageCamouflage2.2. AposematicAposematic3.3. MimicryMimicry

1.1. CamouflageCamouflage

•• Cryptic coloration:Cryptic coloration:a. Hides from predators.b. Example: Example: English Peppered MothEnglish Peppered Moth

2.2. AposematicAposematic

•• Bright colorsBright colorsa. Advertises noxious traitAdvertises noxious traitb. Example: Example: Monarch ButterflyMonarch Butterfly

3.3. MimicryMimicry

•• Two examples:Two examples:1.1. Mullerian MimicryMullerian Mimicry: when two unpalatable

species mimic each other in the same habitat.

2.2. Batesian MimicryBatesian Mimicry: palatable species mimic unpalatable species.

Keystone PredatorKeystone Predator

• A predatorpredator the maintains species diversity in a community.

•• ReducesReduces the density of the strongest competitors in a community.

•• Example:Example:1.1. RedRed--tailed hawktailed hawk2.2. CoyoteCoyote3.3. Harvester antHarvester ant

Symbiotic RelationshipsSymbiotic Relationships

•• Help structure communities.Help structure communities.

•• Three examples:Three examples:1.1. ParasitismParasitism2.2. CommensalismCommensalism3.3. MutualismMutualism

1.1. ParasitismParasitism

• Symbiotic relationship which benefits one benefits one organismorganism and harms the otherharms the other.

• Example:Example:1.1. Tick on a coyoteTick on a coyote2.2. Tapeworm in a dogTapeworm in a dog3.3. Flea on a catFlea on a cat

2.2. CommensalismCommensalism

• Symbiotic relationship which benefits one benefits one organismorganism while the other is unaffectedother is unaffected.

•• Example:Example:1.1. Cattle egrets and cattle in fieldCattle egrets and cattle in field

3.3. MutualismMutualism

• Symbiotic relationship which benefits both benefits both organismsorganisms.

•• Examples:Examples:1.1. Acacia ants and acacia treeAcacia ants and acacia tree2.2. Termites and gut protozoaTermites and gut protozoa3.3. Legumes and nitrogenLegumes and nitrogen--fixing bacteriafixing bacteria

Ecological SuccessionEcological Succession

•• TransitionTransition in species compositionspecies composition over ecological timeecological time.

•• Three examples:Three examples:1.1. Primary SuccessionPrimary Succession2.2. Secondary SuccessionSecondary Succession3.3. Climax CommunityClimax Community

1. Primary Succession1. Primary Succession

• Occurs in areas where no community existedno community existedbefore (first succession).(first succession).

•• Example:Example:1.1. New volcanic islands New volcanic islands -- lichenslichens

2. Secondary Succession2. Secondary Succession

• Occurs in disturbed habitatsdisturbed habitats where some soil, and perhaps some organisms, still remain after the disturbancedisturbance.

•• Example:Example:1.1. FiresFires2.2. FloodsFloods3.3. DroughtDrought

3. Climax Community3. Climax Community

•• CommunityCommunity that remains essentially the same over long periods of time.

• It is the final stagefinal stage of ecological successionecological succession.

Trophic StructureTrophic Structure

• The different feeding relationshipsdifferent feeding relationships that determine the route of energy flowroute of energy flow and the pattern of chemical cycling.

• According to the ““rules of ten,rules of ten,”” approximately 10% of the potential energy10% of the potential energy stored in the bonds of organic molecules at one trophic leveltrophic level fuels the growth and developmentgrowth and development of organisms at the next trophic leveltrophic level.

Trophic StructureTrophic Structure

•• Five examples:Five examples:1.1. Primary ProducersPrimary Producers2.2. Primary ConsumersPrimary Consumers3.3. Secondary ConsumersSecondary Consumers4.4. Tertiary ConsumersTertiary Consumers5.5. Decomposers and DetrivoresDecomposers and Detrivores

1. Primary Producers1. Primary Producers

•• Autotrophs:Autotrophs: which make up the trophic trophic levellevel of an ecosystem that ultimately supports all other levels.

•• Examples:Examples:1.1. Mostly photosynthetic organismsMostly photosynthetic organisms

2. Primary Consumers2. Primary Consumers

•• HerbivoresHerbivores: organisms in the trophic leveltrophic levelof an ecosystem that eat plants or algae.

•• Examples:Examples:1.1. GrasshopperGrasshopper2.2. MouseMouse

3. Secondary Consumers3. Secondary Consumers

• The trophic leveltrophic level of an ecosystem consisting of carnivorescarnivores that eat herbivoresherbivores.

•• Examples:Examples:1.1. SnakeSnake2.2. Green sunfishGreen sunfish

4. Tertiary Consumers4. Tertiary Consumers

• The trophic leveltrophic level of an ecosystem consisting carnivorescarnivores that eat other carnivorescarnivores.

•• Examples:Examples:1.1. HawksHawks2.2. Mountain lionsMountain lions

5. Decomposers and Detrivores5. Decomposers and Detrivores

•• HeterotrophsHeterotrophs that get their nutritionnutrition by breaking downbreaking down the organic compoundsorganic compoundsfound in waste organic matterwaste organic matter and dead dead organismsorganisms.

5. Decomposers and Detrivores5. Decomposers and Detrivores•• Examples:Examples:

A.A. Decomposers:Decomposers: 1. Bacteria1. Bacteria2. Fungi2. Fungi

B. Detrivores:B. Detrivores: 1. Worms1. Worms2. Nematodes2. Nematodes3. Insects3. Insects4. Lobsters4. Lobsters5. Shrimp5. Shrimp6. Condors6. Condors

Trophic StructureTrophic Structure

Primary Producers: grass (Primary Producers: grass (10,000 KCAL10,000 KCAL))

Primary Consumer: grasshopper (Primary Consumer: grasshopper (1,000 KCAL1,000 KCAL))

Secondary Consumer: mouse (Secondary Consumer: mouse (100 KCAL100 KCAL))

Tertiary Consumer: snake (Tertiary Consumer: snake (10 KCAL10 KCAL))

Food ChainFood Chain

• The transfer of food from trophic leveltrophic level to trophic leveltrophic level.

•• Example of a food chain:Example of a food chain:

1.1. Primary producer:Primary producer: phytoplanktonphytoplankton2.2. Primary consumer:Primary consumer: zooplanktonzooplankton3.3. Secondary consumer:Secondary consumer: fishfish4.4. Tertiary consumer:Tertiary consumer: fishermanfisherman5.5. Quaternary consumer:Quaternary consumer: sharkshark

Food WebFood Web

• The map of all interconnectionsinterconnections between between food chainsfood chains for an ecosystem.

BiomassBiomass

• The amount or mass of organic materialorganic material in an ecosystemecosystem.

Primary ProductivityPrimary Productivity

• Is the rate where solar energysolar energy is converted to the chemical energychemical energy of organic (glucose) organic (glucose) compoundscompounds by autotrophs (plants).autotrophs (plants).

•• Net primary productionNet primary production equals equals photosynthesis photosynthesis -- cellular respirationcellular respiration

Tropical Rain ForestTropical Rain Forest

• Occur in equatorialequatorial areas

• High abundance of yearly rainyearly rain(>250 cm a year in some areas)

• Has the highest numberhighest number of different different species per square mile.species per square mile.

Tropical Rain ForestTropical Rain Forest

•• Human impacts a great concern:Human impacts a great concern:

1.Clear cutting for wood and farmland.

2.May cause large scale changes in world climate.

3.There will be a large scale loss of species.

Negative Impacts to EcosystemsNegative Impacts to Ecosystems

1.1. ClearClear--cuttingcutting of forest upsets chemical cycling.

2.2. Eutrophication:Eutrophication: increased mineral input which chokes aquatic life.

3.3. Environmental disasters:Environmental disasters: “Valdez Oil Spill”

4.4. Pollution:Pollution: water, air (acid rain), pesticides and herbicides.