What shapes an What shapes an ecosystem?ecosystem?

TSW identify and describe TSW identify and describe interactions between interactions between

individuals in a communityindividuals in a community

Biotic & Abiotic FactorsBiotic & Abiotic Factors

Biotic: LivingBiotic: Living Abiotic: Non-Abiotic: Non-

livingliving Can you think of Can you think of

any examples?any examples?

What is a niche?What is a niche?

DefDef: The full range of physical & : The full range of physical & biological conditions in which an biological conditions in which an organism lives & the way in which an organism lives & the way in which an organism uses those conditionsorganism uses those conditions

An organism’s occupationAn organism’s occupation Includes place in the food web, range Includes place in the food web, range

of survivable temps, type of food of survivable temps, type of food eaten, physical conditions needed for eaten, physical conditions needed for survival…survival…

What determines the # of What determines the # of niches in an ecosystem?niches in an ecosystem?

The combination The combination of biotic and of biotic and abiotic factors in abiotic factors in an ecosysteman ecosystem

Key PointsKey Points

No two species can share the same No two species can share the same niche in the same habitat niche in the same habitat (COMPETITIVE EXCLUSION (COMPETITIVE EXCLUSION PRINCIPLE)PRINCIPLE)

Different species can occupy niches Different species can occupy niches that are similarthat are similar

CompetitionCompetition

Organisms of the Organisms of the same or different same or different species attempt to species attempt to use an ecological use an ecological resource in the resource in the same place at the same place at the same timesame time

Usually results in a Usually results in a winner & a loserwinner & a loser

PredationPredation

One organism captures & feeds on One organism captures & feeds on another organismanother organism

SymbiosisSymbiosis

Relationship where any 2 species live Relationship where any 2 species live closely togetherclosely together

3 Main Types3 Main Types– MutualismMutualism– CommensalismCommensalism– ParasitismParasitism

MutualismMutualism

Both species Both species benefit from the benefit from the relationshiprelationship

(+, +)(+, +) ExampleExample: :

Flowers/InsectsFlowers/Insects

CommensalismCommensalism

One member of the One member of the association association benefits, while the benefits, while the other is nether other is nether helped, nor harmedhelped, nor harmed

(+, +/-)(+, +/-) ExampleExample: :

Barnacles/ManateeBarnacles/Manateess

ParasitismParasitism

One organism lives on or in another One organism lives on or in another organism causing it harmorganism causing it harm

The parasite obtains all or some of its The parasite obtains all or some of its nutritional needs from the hostnutritional needs from the host

ExampleExample: Fleas, ticks, lice/ Mammals: Fleas, ticks, lice/ Mammals

Ecological SuccessionEcological Succession

The series of predictable changes The series of predictable changes that occurs in a community over timethat occurs in a community over time

11º Successionº Succession

On land, succession that occurs on On land, succession that occurs on surfaces where no soil existssurfaces where no soil exists

22º Successionº Succession

Occurs when a disturbance of some Occurs when a disturbance of some kind changes an existing community kind changes an existing community without removing the soilwithout removing the soil

Pioneer---------Pioneer--------- Climax Climax CommunityCommunity

The 1The 1stst set of set of species to move species to move into an area after a into an area after a disrupting eventdisrupting event

Example: Corals Example: Corals moving onto a moving onto a sunken shipsunken ship

Mature, stable Mature, stable community (can community (can still undergo still undergo changes)changes)

Example: Volcanic Example: Volcanic wasteland turning wasteland turning into a rainforestinto a rainforest