Principles of Principles of EcologyEcologyUnit 2Unit 2Chapter 2Chapter 2

What is ecology?What is ecology?

EcologyEcology: study : study of interactions of interactions that take place that take place between between organisms and organisms and their their environmentenvironment

BiosphereBiosphere

the portion of the Earth that supports the portion of the Earth that supports living thingsliving things

Ex: ocean, forest, atmosphere.Ex: ocean, forest, atmosphere.

Abiotic vs. Biotic factorsAbiotic vs. Biotic factors

AbioticAbiotic = nonliving parts of the = nonliving parts of the environmentenvironment Ex: light, air, temperature, soilEx: light, air, temperature, soil

BioticBiotic = living parts of the environment = living parts of the environment Ex: bacteria, protist, fungus, plant, Ex: bacteria, protist, fungus, plant,

animalanimal

Levels of organization Levels of organization from smallest to largestfrom smallest to largest

IndividualIndividual PopulationPopulation CommunityCommunity EcosystemEcosystem

IndividualIndividual

made of cells, uses energy, reproduces, made of cells, uses energy, reproduces, responds, grows, and developsresponds, grows, and develops

PopulationPopulation

group of organisms all of the same group of organisms all of the same species, which interbreed and live in the species, which interbreed and live in the same area at the same timesame area at the same time

CommunityCommunity

interacting populations in a certain area interacting populations in a certain area at a certain timeat a certain time

EcosystemEcosystem

interacting communities and abiotic interacting communities and abiotic factorsfactors

Habitat vs. NicheHabitat vs. Niche

HabitatHabitat: place where organism lives: place where organism lives

NicheNiche: role or position a species has in : role or position a species has in its environmentits environment

Habitats are capable of Habitats are capable of changing.changing.

What can lead to changes in habitats?

Symbiosis: interactions Symbiosis: interactions between two speciesbetween two species

MutualismMutualism: both benefits: both benefits

CommensalismCommensalism: one benefits, the other : one benefits, the other unaffectedunaffected

ParasitismParasitism: one benefits, one is harmed: one benefits, one is harmed

MutualismMutualism

Clownfish is protected, while providing a lure for the anemone.

Some say that this relationship can be commensalistic.

CommensalismCommensalism

Volcano sponge using the crinoid sponge as a “lift” for increased filtration but the crinoid sponge is unaffected.

ParasitismParasitism

Head lice

How organisms obtain How organisms obtain energyenergy

AutotrophAutotroph (producer): photosynthetic or (producer): photosynthetic or chemosynthetic, makes own foodchemosynthetic, makes own food

HeterotrophHeterotroph (consumer): “eat” other (consumer): “eat” other organisms, cannot make own foodorganisms, cannot make own food

DecomposerDecomposer: breaks down dead or : breaks down dead or decaying organisms, recycles matterdecaying organisms, recycles matter

AutotrophAutotroph

Heterotrophs - Heterotrophs - scavengersscavengers

ScavengersScavengers: feed off of dead or : feed off of dead or decaying living things but do not recycle decaying living things but do not recycle matter back into the ecosystemmatter back into the ecosystem

Heterotrophs - Heterotrophs - herbivoresherbivores

consume only consume only vegetative mattervegetative matter

mostly mostly primary primary consumersconsumers..

Heterotrophs - carnivoresHeterotrophs - carnivores

obtain energy from obtain energy from eating other eating other consumersconsumers

Secondary and Secondary and tertiary consumerstertiary consumers

DecomposersDecomposers

Typical examples: fungus and bacteria

Food chainFood chain

shows how matter and energy move shows how matter and energy move through an ecosystem (one route)through an ecosystem (one route)

berries → mice → black bear

Food webFood web shows shows

interactions interactions between between organisms organisms (all possible (all possible routes)routes)

Energy pyramidEnergy pyramid

Shows how Shows how much much energy is energy is available at available at each each trophic trophic (energy) (energy) levellevel

Pyramid of Energy

Heat

Heat

Heat

Heat

0.1% Consumers

1% Consumers

10%

Consumers

Parasites, scavengers, and

decomposers feed at each

level.

Autotrophs

First-order heterotrophs

Third-order heterotrophs Second-order

heterotrophs

Decomposers

Four cycles in natureFour cycles in nature

Water cycleWater cycle Carbon cycleCarbon cycle Nitrogen cycleNitrogen cycle Phosphorus cyclePhosphorus cycle

Water cycleWater cycle

Carbon cycleCarbon cycle

Nitrogen cycleNitrogen cycle

Phosphorus cyclePhosphorus cycle