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Ecology

Our Environment

A Quote

This we know...

The earth does not belong to man, man belongs to earth.

All things are connected, like the blood which connects onefamily.

Whatever befalls the earth befalls the children of the earth.

Man did not weave the web of life - he is merely a strand in it.

Whatever he does to the web, he does to himself.

- Chief Seattle, 1854

A Quote

We do not inherit the earth from our

ancestors,

We borrow it from our children.

-Native American Proverb

Do Now

•Find your match and draw a

picture that describes the

vocabulary word. Be prepared

to share your drawing with the

class.

•What is it?

• The study of relationships b/w living

things (plants, animals, & other

organisms) with one another & their physical surroundings (natural

resources) such as air, soil, and

water.

ECOLOGY

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Ecologists

•study ecology at different

levels

PHYSICAL ENVIRONMENT

•Abiotic = non-living factors

List Some Abiotic Factors?

Abiotic Factors

– Light (intensity & duration)

– Temperature range (fluctuations, daily &

seasonal)

–Water amt.

– Landscape (topography)

– Soil (type, minerals, pH)

– Temperature (warm temp-less O2; cold water-

more O2)

–CO2, Oxygen amount

LIVING ENVIRONMENT

•Biotic = living factors

List Some Biotic Factors?

LIVING ENVIRONMENT

• Biotic (living) Factors

–Plants

–Animals

–Fungi

–Bacteria

–Protozoa

–Everything alive!

Ecological Organization (Biotic)

• Species– A group of similar organisms capable of inter-breedingand producing fertileoffspring

Example: Bullfrogs

• Population– All the members of a single species inhabiting a given location

Example: All the Bullfrogs in a lake

• Community– All the interacting populations in a given area

Example: All the fish, frogs, plants, etc. in a lake

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Ecological Organization(Biotic & Abiotic)

• Ecosystem– All the living (biotic) & nonliving (abiotic) factors interacting (functioning together) as an independent, stable system

– These interactions result in a balancethat allows the ecosystem to be self-sustaining (independent)

Ecological Organization(Biotic & Abiotic)

• Biome– A large geographical area with similar vegetation types

• Biosphere

- all ecosystems on Earth whereall life is found

•Land

•Water•Air

Ecological Organization

Simple

Complex

Test Yourself (Organizational Levels)

• A guppy = ?• A hermit crab = ?

• A cat = ?• A dog = ?• All the hermit crabs in Mrs. Reece’s house = ?

• All the cats in Mrs. Reece’s house = ?• All the animals (people too!) in Mrs. Reece’s house = ?

• Mrs. Reece’s house = ?

Copy Into Your Notebook

• Pond

• Minnows

• Aquatic plants

• Entire population of different organisms

• The community of animals, plants and

micro-organisms, together with the habitat where they live

Analyze The Picture & Identify Each(community, habitat, ecosystem, population)

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Answers

• Pond

• Minnows

• Aquatic plants

• Entire population of different organisms

• The community of animals, plants and

micro-organisms, together with the habitat where they live

(Habitat)

(Population)

(Population)

(Community)

(Ecosystem)

Factors For

A Stable

Ecosystem &

Organism

Survival

Ecosystems

• Self-sustaining ecosystems must

have:

– Constant source of energy

– Ability to change this energy into organic molecules

– Cycle minerals & nutrients between organisms & the environment

Organism Requirements

•Basic Needs

–Food

–Water

–Shelter

•Other Needs

–Reproductive

–Social

Organisms go about getting these needs in very specific ways!

Ecosystems & Populations

• Populations change size based on

the resources available.

• Without limitations, populations

increase.

• Factors in the environment can limit

the size of a population- called

limiting factors

Limiting Factors

•Abiotic & Biotic are examples of limiting factors.

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Population Limiting factors

•Abiotic– Light

– Temperatures– Moisture– Soil Nutrients

– pH– Pollutant concentrations

•Biotic– Food Availability

– Disease– Predation– Competition from other organisms

– Mating opportunities

Examples

• Abiotic1. Extreme heat

- limits type of species to survive in desert

2. Water temp.

- limits types of fish that live in water

• Biotic

1. Predator-prey

relationships

(Coyote predator-

limits # of deer

(prey) in forest)

Factors Limiting Population Size

1. Predator-prey - Predation (1 organism eats another)

2. Competition

3. Carrying Capacity

1. Predator-Prey: Whose Who?

• Controls (limits) population size, if

left undisturbed population

remains BALANCED.

Predator = kills & eats organism

Prey = organism eaten

Case Study: The Lynx & The Hare

• The rise and fall in numbers of Canadian lynx and its favorite prey the snowshoe hare. The two populations were estimated each year for some 75 years from the number of animals caught by fur traders. The lynx population was found to rise and fall in a ten-year cycle, with that of the hare following two years behind. No other cat is so dependent on a single prey species, which is why there is such a clear pattern of interdependence between the two populations.

An Interdependent Relationship

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Predator-Prey Dynamic

• The relationship (graph) between

the 2 will look similar.

Ex: If prey population increases, so does the predator population

http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel/

environment/populationsandpyramidsrev6.shtml

2. Competition

• Organisms can compete for the

same resources such as food, shelter, territory (space), etc.

• Competition can be between

members of the same species or different species

Competition

• When resources are FINITE (limited)

& the demand for resources is

greater than the supply………

ORGANISMS COMPETE!

Competition

• Plants compete

with each other for:

• light (for photosynthesis)

• water, and

• nutrients

(minerals)

• Animals compete

with each other for:

• food

• water

• Mates ( for reproduction)

• living space

Reducing Competition

• To reduce competition for food

different species evolve to NOT

occupy exact ecological niches.

Ex: Different finch species feeding in spruce tree

An Ecological Niche

• The specific “role” or “job” that an organism plays in its environment

• Its daily routine

• What the organism does in its environment

– Where & how they get food

– Where & how they hide

– Where & how they nest

– Where & how they breed

– Etc., etc., etc., etc., etc., ……….

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Competition between 2 Paramecium species. One species will win, the other will lose.

3. Carrying Capacity

• The total number of

organisms that a certain

area can support.

• Organisms DO NOT

overpopulate due to

FINITE resources like

food, space, H2O

Carrying CapacityBirth rate = death rate population

- No increase

# squirrels in 1 square

mile of a forest

Wrap-Up: Fill In

Population Size

May Be Limited By

Predators

Competition(food, space, mates)

FiniteResources(H2O, food,space)

Disease

Human Disturbances

(habitat

destruction)

Activity: Answer These Questions

Based on Your Analysis (On Board)

• Name some decomposers.

• What role does the tree trunk play for the insects, caterpillars, & larvae?

• Identify the different ecological niches for the following organisms:

- squirrels, fungi, bees, blue tits,

sparrow hawks

• Do the bluetits & squirrels inhabit the same tree?

• Do the bluetits & squirrels occupy the same or different niche within the oak ecosystem?

Oak Tree Ecosystem

Each zone of the tree is home to a distinctive community of organisms

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Answers

• Bacteria, woodlice, and earthworms feed off last year's leaves, acorns & fungi grown on its roots

• The trunk layer provides shelter or food to insects, caterpillars and larvae.

• Squirrels (gather acorns), fungi (grows on roots) bees (gather pollen, nectar), bluetits(hunt moth larvae),

sparrowhawks (hunt small birds)

• Yes

• Different niches

Nutritional

Needs

In Ecological

Communities

Nutritional Relationships

•How do organisms acquire

nutrients and energy?– Make their own food--Autotrophs

•OR

– Get it from other organisms--Heterotrophs

Autotrophs

• Auto = self Troph = food, feeding

• Also called producers

• Synthesize their own food from inorganic materials & an energy source

or convert solar energy

into food energy

-Ex: green plants

Heterotrophs

• Hetero= different Troph= food, feeding

• Also called consumers

• Organisms are dependent on other organisms for food

• Categorized by what they eat and how

they acquire it.

5 Categories of Heterotrophs

1. Decomposers (Saprophytes)

2. Scavengers

3. Herbivores

4. Carnivores

5. Omnivores

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1. Decomposers

• Organisms that obtain its nutrients

from nonliving organic matter

(dead plants, dead animals)

Ex: bacteria, fungi (molds, yeasts), certain plants) insects (Dung beetle), earthworms

Indian Pipe (Plant)

Decomposer’s Role

• Eat dead materials to break down

into chemical parts like nitrogen, carbon & other nutrients so plants

& animals can use.

Dung Beetle Recycling Nutrients

2. Scavengers

• Animals that consume (eat)

already dead animals.

• Are carnivores.

Ex: turkey vultures, crows, burying beetles, hyenas

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Without decomposers and scavengers, the world would be covered with

dead plants and animals!

Did You Know? 3. Herbivores

• Animals that consume (eat) plants,

algae, phytoplankton

Deer

Cow

Grasshopper

4. Carnivores

• Animals which consume other animals

– Predators:

• animals which kill and consume their preyOwl

Polar bears

Wolf

Frog Video

Carnivorous Plant: Venus Flytrap

5. Omnivores

• Animals that consume both plant

& animals.

RaccoonBrown bear

Energy Flow

• All organisms need energy to carry on life processes (build new cells, chemical reactions, movement)

• The Sun is the ultimate source of energy in ecosystems

• How does the energy from the Sun flow

through ecosystems?

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1. Mouse receives

energy from food

it eats.

2. Mouse uses energy from food to

survive (growth, keep warm, capture

food, escape predators). Heat is lost from body.

4. Energy is lost in

wastes (feces)

3. 90% of energy

in mouse’s food is

used or lost. 10% is available for

predators

The Pathway of Food Energy Is

Represented BY

1. Food Chains

2. Food Webs

2. Ecological Pyramids

http://magma.nationalgeographic.com/ngexplorer/0309/quickflicks/in

dex.html

1. Food Chains(ENERGY FLOW)

- a model that shows how energy moves through an ecosystem from the producer to the consumers.

SUN

PRODUCER

Primary

Consumer (Herbivore)

Secondary

Consumer (Carnivore)

Tertiary

Consumer (Carnivore)

Decomposers

Describe the orderof the food chain.

2. Food Webs (ENERGY FLOW)

- a complex

model that

shows how food chains

overlap in an

ecosystem.

Why is the Food Web More Complex than the Food Chain?

•Because 1 species eats more than 1 type of organism

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Direction of Energy Flow

Herbivore

Consumer

Omnivore

SecondaryConsumer

Carnivore

Tertiary Consumer

DecomposerEnergy

SourceProducer

Return Nutrients To

autotrophs

3. Ecological Pyramids

• A pyramid that

shows the transfer

of energy flow using

food chains.

• Pyramid represents

the amount of:

- Energy

- Biomass

- Numbers

Trophic

levels

What Do Ecological Pyramids

Tell Us?

1. Pyramid of Energy

- each step (trophic level/ feeding level)up, 90% of energy is LOST because its used by organism to stay alive for cellular processes then lost by body heat.

- each level passes 10% of its stored energy to next level up to make new cells.

1. Pyramid of Energy

Important!

Energy

CAN NOT

Be RECYCLED

2. Pyramid of Biomass

- the total mass

of living matter

(weight) that is

consumed

by the level

above it.

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3.Pyramid of Numbers

• the numbers of organisms that exist

at trophic levels in an ecosystem.

Exercise: What Percentage of Energy is Passed Upward? Complete the Pyramid of Energy

1000 Kcal

100 Kcal

10 Kcal

Bluegrass

Insects & worms

Ants & spiders

Birds

Does this

illustration represent a Pyramid of

Energy, a Pyramid of Biomass, or a

Pyramid of Numbers?

Pyramid of

Biomass

1. Where is

energy mostabundant (in

greatest

amount)?

Producers

Identify: (Food Web, Ecological

Pyramid, Food Chain)A.

B.C.

Summary

• Available food energy, biomass, &

# of organisms DECREASE as you

move UP the pyramid

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A Food Chain Environmental Problem -

Biomagnification

- An increase concentration of pollutants along a food chain

How does DDT become concentrated in the tissues of organisms at each

trophic level in a food chain?

• DDT is

metabolized &

excreted more

slowly & builds up

in fat.

• Results:

Organisms at the

TOP of the food

chain are at

greatest risk.

Incre

ase

concentration o

f DDT

DDT used on an

agricultural field & rainstorm washes it into

nearby streamphytoplankton

DDT inhibits the

deposition of calcium

Species

declined

What Are The

Symbiotic Relationships

In An Ecosystem?

Label These Pictures:Mutualism, Commensalism, Parasitism

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Symbiotic Relationship

(Symbiosis)

• A close relationship between 2 species.

Types of Symbiotic Relationships

1. Mutualismo 2 organisms live closely together & both

benefit. Anemone protects

the clownfish & gives it a safe home

because the anemone has

poisonous tentacles that does not harm

the clownfish.

Clownfish clean the

anemone by eating the leftover algae &

food. Also, chases away predators

(butterfly fish) from the anemone

Mutualism

Other Examples:

• Bees & flowers (flower gets pollinated)• Human intestinal bacteria (bacteria gets

food, humans get vitamins)

• Hippos & birds (Hippo gets cleaned, birds get food & shelter)

• Lichen (fungus & algae) (Lichen provides a habitat for algae, algae provides food for fungus)

• Wrasses & cleaner shrimp (Both eat dead skin, parasites, and scrapes of food off of fish & clean mouth & gills; not harmed by the bigger fish)

• Nitrogen-fixing bacteria on legume nodules (bacteria live in plant roots, plants get a usable form of nitrogen in nodules to use for maintenance, bacteria gets carbohydrates (nutrient, energy) from plant via photosynthesis)

Mutualism

Bee gets food (pollen)

Flower can get pollinated

because the pollen sticks to the bee’s body & fertilizes it (the pollen contains the sperm

cells).

Bacteria gets food,

human gets protection - vitamins

Legume nodules

Mutualism

Hippopotamusallows birds to prey on the parasites that feed on him even opening its mouth for bird to safely hunt. Bird has food & is safe.

Lichens

Fungus holds water for algae, algae can photosynthesize & give food to fungus

Hippos

Hippo gets cleaned, birds get food & safety

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Cleaner shrimp & wrasse fish providing a cleaning service

2. Commensalism

o One organism benefits and the other is unaffected

Examples:

• Shark and remora (remora eats the scraps of fish from the shark without harming the shark)

• Epiphytes (orchids) (no roots in soil, found high in trees, doesn’t get nutrients from the tree)

• Barnacles and whales (barnacles are crustaceans that find a home on whales to gain food, whale not harmed)

• Pearlfish and sea cucumbers (pearlfish’s home is the anus of the sea cucumber; sea cucumber is not harmed)

• Lichen & tree (lichen gains more sunlight; no harm to tree)

Shark & Remora away

to obtain a food source & safety

Epiphytes – gets nutrients

from air, falling rain, greater access to sunlight, seeds can

be dispersed by wind

Barnacles find their

habitat on whales to find nutrients where it

can be transported to new sources of food

not harming the organism

Pearlfish lives inside the anus during

the day & comes out at night to search for food

Lichen & tree gets

sunlight, tree not

harmed

3. Parasitism

– One organism benefits while the other is harmed

• Ringworm

•Heartworm & dogs

•Malaria

• Tapeworms

•Deer tick

• Leeches

• Lamprey

• Athlete’s foot & Humans

Parasites depend on host for nourishment;

host weakens, gets infection, or gets ill

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Heartworm Worm gets

nutrients; Dog’s heart weakens

Lamprey gets blood; fish

is wounded & could get infected

Tapeworm gets

nutrients; host is weakened

Closure: Symbiotic Relationships

• Draw this table, fill in using +, -, 0– + = benefits the organism– - = harms the organism– 0 = organism is unaffected

SPECIES A SPECIES B

MUTUALISM

COMMENSALISM

PARASITISM

Answers

SPECIES A SPECIES B

MUTUALISM + +

COMMENSALISM + 0

PARASITISM + -

• Draw this table, fill in using +, -, 0– + = benefits the organism– - = harms the organism– 0 = organism is unaffected

Ecological Succession

Ecological Succession

• A change in an ecosystem where 1 community replacesanother due to changes in abiotic & biotic factors.

Plants grow using

soil nutrients then die & return nutrients

to soil

Animals feed on

plants & leaves wastes

Bacteria, fungi,

insects live off decaying stuff &

replace it in soil

A Changing Ecosystem

Primary Succession•The development of a community in

an area of rock with no topsoil

Secondary Succession•The return of a community to its

original state after a disturbance (flood, fire, or windstorm). Soil remains & plants

are the 1st species to develop.

2 Types of Ecological Succession

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Lichens & moss secrete acids die decay material & rock make soil

Pioneer species

Forest fire, soil remains

Primary

Succession

Secondary

Succession

Grass, small shrubs,

soil enriches

Grass, tall shrubs,

small trees. Soil enriched

Tall shrubs & trees,

animals. Soil enriched

1. Does a community exists in this illustration?

2. Which one(s) are considered the pioneer species?

Yes, a community of plants (grasses, flowers, shrubs, trees)

annual plants

120 yrs

Seeds flown by birds & animals debrisincreases & settles on bottom of pond so pondweed grows emergent plants from water grow & decay more build-up on pond floor rises marsh & animals, more debris swamp dried pond becomes forest, grassland)

A Pond

Succession

Hawaii’s Primary Succession on

Lava Flows

1. Is This Primary or Secondary Succession?

2. Why?

3. Prediction: What Do You Think Was The First Pioneer Species

In This Picture?

Primary

Developed from rock

Lichens, Moss