EcologyEcology Ecology is the scientific study of the Ecology is the scientific study of the

interaction between organisms and interaction between organisms and between organisms and their between organisms and their environment.environment.

How do animals benefit How do animals benefit plants?plants?

What non-living things in What non-living things in their environment do their environment do

organisms interact with?organisms interact with?

Levels of OrganizationLevels of Organization

1. Biosphere1. Biosphere 2. Biome2. Biome 3. Ecosystem3. Ecosystem 4. Community4. Community 5. Population5. Population 6. Organism6. Organism

Can a group of rabbits Can a group of rabbits and a group of field mice and a group of field mice

make up the same make up the same population?population?

Could a biome near Brazil Could a biome near Brazil be the same as a biome be the same as a biome

in northern Canada?in northern Canada?

EcosystemsEcosystems

An ecosystemAn ecosystem

consists of a consists of a given area’s given area’s

(______________) (______________) andand

(______________). (______________).

abiotic factors

biotic factors

physical features

living organisms

Abiotic factorsAbiotic factors

nonliving physical nonliving physical parts of an parts of an ecosystem such as ecosystem such as _______________ _______________ type, rocks, type, rocks, temperature,temperature,

_______________, _______________, and rainfall.and rainfall.

water, sunlight, soil

humidity, elevation

Wind: Can affect the pattern of a plant’s growth

Biotic FactorsBiotic Factorsliving aspectsliving aspects of an ecosystem of an ecosystem such such as_____________as_____________

_______________, _______________, worms, amoebas, worms, amoebas, and waterlilies.and waterlilies.

fishes, frogs, insects, snails,

HabitatsHabitats

Ecosystems contain Habitats,the location or surrounding where the organism lives

Niches,Niches, the behavior of organisms in their habitats.

CommunityCommunityorganisms living together in an ecosystemorganisms living together in an ecosystem

Ecological MethodsEcological Methods

Scientists conduct research using 3 Scientists conduct research using 3 basic approaches.basic approaches.

1. Observing – could be behavior 1. Observing – could be behavior observations about an animal.observations about an animal.

2. Experimenting – test a hypothesis2. Experimenting – test a hypothesis 3. Modeling – gain insight into 3. Modeling – gain insight into

complex phenomena like global complex phenomena like global warming.warming.

Notes: 3-2 Energy Notes: 3-2 Energy FlowFlow

Sunlight is the Sunlight is the main energy main energy source for life on source for life on Earth.Earth.

AutotrophsAutotrophs – – capture energy capture energy from sunlight and from sunlight and use that energy use that energy to produce food. to produce food. Also called Also called producers.producers.

Producers

Photosynthesis is responsible for adding oxygen to—and removing carbon dioxide from—Earth's atmosphere.

HeterotrophsHeterotrophs – rely on other – rely on other organisms for their energy and food organisms for their energy and food supply. Also called consumers.supply. Also called consumers.

Herbivores – eat plantsHerbivores – eat plants Carnivores – eat animalsCarnivores – eat animals Omnivores – eat bothOmnivores – eat both Detritivores – eat dead matter (mites, worms, Detritivores – eat dead matter (mites, worms,

snails, crabssnails, crabs

Food ChainsFood Chains Food ChainsFood Chains – a series of steps in – a series of steps in

which organisms which organisms transfertransfer energy by energy by eating and being eaten.eating and being eaten.

Example:Example: plankton –dragonfly- plankton –dragonfly-salamander-snake salamander-snake

CC. . Feeding RelationshipsFeeding Relationships

1.1.        Food chainFood chain: :

a. chains are found in harsh a. chains are found in harsh climates like the desert and tundra . climates like the desert and tundra .

b.b.    Desert or tundra areas are Desert or tundra areas are

than those found than those found in in more moderate climatic influences more moderate climatic influences e.g. e.g.

follow the progression of energy flow from one organism to another or “who eats whom.”

shorter food

less stable and more easily destroyed

tropical rain forests.

Food WebFood Web Food WebFood Web – links all the food chains – links all the food chains

in an ecosystem together.in an ecosystem together.

Trophic LevelTrophic LevelEach step in a food chain/web is

called a trophic level. (herbivore)

Pyramids – 3 typesPyramids – 3 types1. Energy Pyramid – transfer of energy from 1. Energy Pyramid – transfer of energy from

one trophic level to the next. Measured one trophic level to the next. Measured in kcals.in kcals.

**10% rule** - only 10% of the energy is **10% rule** - only 10% of the energy is transferred from one trophic level to the transferred from one trophic level to the next.next.

Why? Why? It is lost in respiration, movement and It is lost in respiration, movement and

reproduction.reproduction.

Ecological PyramidsEcological Pyramids0.1% Third-level consumers

1% Second-level consumers

10% First-level consumers

100% Producers

Suppose that the base of an Suppose that the base of an energy pyramid consists of energy pyramid consists of

plants that contain plants that contain 450,000calories of food 450,000calories of food

energy. If the plants were energy. If the plants were eaten by mice and insects, eaten by mice and insects,

how much food energy would how much food energy would be available to those first-be available to those first-

level consumers?level consumers?How about the second-level How about the second-level consumers that at the mice consumers that at the mice

and insects?and insects?How about the third-level How about the third-level

consumer?consumer?

First-level consumer would have 45,000 calories available

Second-level consumer would have 4500 calories available.

Third-level consumer would have 450 calories available.

Feeding RelationshipsFeeding Relationships

Energy flows through an Energy flows through an ecosystem in one direction, ecosystem in one direction, from the sun or inorganic from the sun or inorganic compounds to autotrophs compounds to autotrophs (producers) and then to (producers) and then to various heterotrophs various heterotrophs (consumers).(consumers).

Energy Pyramids Cont’dEnergy Pyramids Cont’d 100 K/cals100 K/cals

1,000 K/cals1,000 K/cals

10,000 K/cals10,000 K/cals

Types of PyramidsTypes of Pyramids 2. Biomass Pyramid – transfer of 2. Biomass Pyramid – transfer of

biomass from one trophic level to the biomass from one trophic level to the next. next.

Types of PyramidsTypes of Pyramids3. Pyramid of Numbers3. Pyramid of Numbers – the total – the total

number of individuals at each trophic number of individuals at each trophic level. (may not look like a pyramid) level. (may not look like a pyramid)