Transcript SHOW Ecology Chapters 3-4

ECOLOGY
Chapters 3 -4
WHAT IS ECOLOGY?
Interactions and Independence
Ecology – study of interactions
among and between organisms
and their environment
Levels of Organization (small to
large)
Species – group of organisms that
can breed and produce fertile
offspring
Populations – groups of the same
species that live in the same area
Communities – groups of different
populations (therefore different
species) that live in the same area
Ecosystem – collection of all of the
organisms that live in a particular
place, together with their nonliving
environment
Biome – a group of ecosystems that
have the same climate and similar
dominant communities
• Examples:
Biosphere – part of Earth in which
life exists including land, water, and
air.
Climate
Places on the earth that have different
climates typically have different living
organisms.
Three major climate zones due to
latitude and angle of heating (earth’s
tilted axis):
• Polar
• Temperate
• Tropical
Section 4-1
Greenhouse
Effect
Different Latitudes
90°N North Pole
Sunlight
Sunlight
Some heat
escapes
into space
Greenhouse
gases trap
some heat
Arctic circle
Sunlight
Most direct sunlight
66.5°N
Tropic of Cancer
Equator
0°
Tropic of Capricorn 23.5°S
Sunlight
Atmosphere
Arctic circle
Earth’s surface
Go to
Section:
23.5°N
Sunlight
66.5°S
90°S South Pole
The World’s Major Land Biomes
Ecological Levels of Organization
Pass It Along
Energy flows in one direction through an
ecosystem, from the sun or inorganic
compounds to producers (organisms that
can make their own food) through
various levels to consumers (organisms
that rely on other organisms for food).
Your body gets the energy and materials
it needs for growth and repair from the
foods you eat.
Energy Flow
Sunlight is the main source of energy for
life on Earth.
Less than one percent of the sun’s
energy that reaches the surface is used
by living things
Autotrophs (producers) – organisms
that use either light energy or inorganic
chemicals make their own food
Photosynthesis – process in which
organisms use light to make their own
food (sugar)
• Examples: plants, algae, some bacteria and
some protists
Chemosynthesis - process in which
organisms use inorganic chemicals to make
food
• Examples: bacteria which live in volcanoes,
hot springs, and deep-sea vents
http://www.youtube.com/watch?v=5Jz
Ugi6YNlY
Heterotrophs (consumers) –
organisms that must eat and cannot
make their own food
Herbivores – eat only plants
•Examples
Carnivores – eat only animals
•Examples
Omnivores – eat both plants and
animals
•Examples
Decomposers – break down
organic material
•Examples
Feeding Relationships
Food Chain – series of
steps in which organisms
transfer energy by eating or
being eaten
Food web – links all of the
food chains in an ecosystem
Trophic Level – each step
in a food chain or food web
What eats what? This is the order:
Producers
Primary consumers
Secondary consumers
Tertiary consumers
Arrows point the direction the
energy or food flows (from food to
“eater”).
A Food Web
Section 3-2
Make your own food web
Ecological Pyramid – a diagram that
shows the relative amounts of energy or
matter contained within each trophic
level of a food chain or web
Energy Pyramid - shows the relative
amount of energy available at each
trophic level.
Energy Pyramid
•Ten Percent Rule - only about
10% of energy available within
one trophic level is transferred to
next level
•Why this inefficiency? List 3
reasons.
Not all of the caterpillar’s food is converted into biomass or
potential energy for a predator.
Biomass Pyramid – shows the
total amount of living tissue
within each trophic level
Pyramid of Numbers – shows
the relative number of organisms
at each trophic level
ECOLOGICAL PYRAMIDS
Terms to know…
Biotic – biological (living)
factors that affect an ecosystem
Abiotic – nonliving (physical)
factors that affect an ecosystem
Abiotic and Biotic Factors
Section 4-2
Abiotic Factors
Biotic Factors
ECOSYSTEM
Go to
Section:
Abiotic and Biotic Factors
Section 4-2
Abiotic Factors
Biotic Factors
ECOSYSTEM
Go to
Section:
Niche – full range of physical
and biological conditions in
which an organism lives and the
way the organisms uses those
conditions
Figure 4-5 Three Species of
Warblers and Their Niches
Section 4-2
Cape May Warbler
Feeds at the tips of branches
near the top of the tree
Bay-Breasted Warbler
Feeds in the middle
part of the tree
Spruce tree
Go to
Section:
Yellow-Rumped Warbler
Feeds in the lower part of the tree and
at the bases of the middle branches
Section 4-2
Interactions in Ecosystems
Organisms not only live together in ecological
communities, but they also constantly interact
with one another. These interactions, which
include predation and competition, help shape
the ecosystem in which they live.
Community Interactions
Competition—an interaction in which
organisms of the same or different species
attempt to use a resource in the same place
and at the same time.
Predation—an interaction in which one
organism captures and feeds on another
animal
Symbiosis – a relationship in which
two species live closely together
Three types of symbiosis:
mutualism = + + (both benefit)
•Examples:
commensalism = + 0 (one
benefits, other little or no
benefit)
•Examples:
parasitism = + - (one
benefits, other harmed)
•Examples:
Termites have bacteria in their guts that help the termites to
digest wood. The bacteria get a nice, warm gut in which they
can live. What relationship is this?
Some orchids grow on trees to get sunlight in dark
forests. The orchid does not hurt the tree. What
relationship is this?
Remora attach to
big fish or whales
and eat the parasites
Remora that grow on the big
fish’s or whales
scales. What
relationship is this?
Remora
attached to a
big fish
This red, sausage-sized structure is
the external portion of an unusual,
parasitic barnacle, Briarosaccus
callosus, found on many species of
king crabs. Here the barnacle is
parasitizing a scarlet king crab,
Lithodes couesi, collected on Pratt
Seamount. The parasite sterilizes
its hosts and uses their energy to
produce hundreds of thousands of
barnacle larvae, which closely
resemble the larvae of the more
typical acorn barnacles. One of the
many unusual features of the
barnacle is its bright red color,
caused by hemoglobin. The
barnacle also induces its crab host
to protect it and also assist with
larval release. Image courtesy of
Tom Shirley
1. The hookworm latches on the walls of the colon with its sharp teeth where it feeds
on blood.
2. The tapeworm is the longest parasite. A mature adult can lay one million eggs per
day.
3. Tapeworm eggs are embedded in the colon.
4. The roundworm can grow to 20 inches (50 cm) long and lay 200,000 eggs per day.
5. Pinworms migrate outside the colon during the night to lay their eggs around the
Ticks suck the blood of animals (including people).
What relationship is this?
Mouth of a
hookworm
Hookworms live in
the intestines of
many mammals
including humans.
They suck blood
from your gut and
can make you sick.
What relationship is
this?
Ringworm (top left and
bottom right) and athlete’s
foot (top right) are both fungi
that live off of human skin.
They both cause irritation
and are very contagious.
What relationships are these?
The Guinea worm
enters the body
through contaminated
water. About a year
later, it breaks through
the skin (usually the
leg) causing an
intense burning
sensation.
When the victim enters water to
relieve the burning, the worm
releases its larvae, ready to infect
more people.
Pseudoscorpions
hitching ride on a
fly’s leg, Costa
Rica.
Pseudoscorpions,
tiny relatives of true
scorpions, often
engage in the
practice of phoresy,
or hitchhiking. What
relationship is this?
A remarkable 3-way
mutualism appears to have
evolved between an ant, a
butterfly caterpillar, and an
acacia in the American
southwest. The caterpillars
have nectar organs which the
ants drink from, and the
acacia tolerates the feeding
caterpillars. The ants appear
to provide some protection
for both plant and caterpillar.
Research of Diane Wagner,
American Museum of
Natural History Southwestern
Research Station
A critical phase in the life cycle of plants is the
proper dispersal of its seeds. Many wonderful
or strange adaptations have evolved to insure
this dispersal. One of these adaptations is the
evolution of recuved spines on the seeds or
seedpods to attach the seeds to the fur of
passing vertebrates who carry the seeds away
from the parent plant. In the case of humans,
fur is replaced by pants, sweaters, socks, and
other pieces of clothing. Plants, therefore,
anticipated the invention of velcro from
several million years. The plant benefits from
the relationship by the dispersal of its seeds.
The vertebrates are not affected except,
perhaps, by being annoyed.
One of the most famous examples are the
burdocks, common weeds found along
roadsides and in empty lots and fields. The
species on the left is the Great Burdock
(Arctium lappa). The seed heads (burs) of
burdocks long spines with hooked tips. The
hooked tips catch onto the hair of passing
vertebrates (cows, deer, dogs, humans) and
the burs are carried elsewhere until they
finally drop off or are pulled off by the carriers.
The anemonefish lives among
the forest of tentacles of an
anemone and is protected from
potential predators not immune
to the sting of the anemone. The
anemonefish is protected from
the sting of the anomone
tentacles by a substance
contained in the mucous on its
skin.
Some consider this relationship
to be a case of mutualism,
claiming that the anemonefish
chases away other fish that
might prey on the anemone.
However this aspect of the
relationship is not well
documented.
CYCLES OF MATTER
Unlike the one-way flow of energy,
matter is recycled within and
among ecosystems
Biogeochemical cycles pass
molecules around again and again
The Cycles
Water Cycle
Carbon Cycle
Nitrogen Cycle
Phosphorus Cycle
We will focus on the nitrogen cycle.
The Nitrogen Cycle
Go to
Section:
The Nitrogen Cycle
All living things need nitrogen as a nutrient.
Nitrogen gas makes up 78% of our atmosphere
and yet animals and plants cannot use nitrogen
gas as a nutrient. So what’s an animal or plant
to do?
How do animals get nitrogen? They eat
protein!
How do plants get nitrogen? From
bacteria that are in the soil or in the
roots of some plants.
Plants can only use nitrogen when it is in
the form of nitrate (NO3-) or nitrite (NO2-).
Decomposers breakdown organic material
(e.g. dead plants and animals) in the soil.
Nitrogen comes from broken down proteins
and DNA.
Some bacteria live in the soil and help to
convert nitrogen into usable forms for plants.
Plants absorb this useable nitrogen from the
soil into their roots.
Nitrogen Fixation – when nitrogen gas is
converted into useable nitrogen by bacteria
Some bacteria actually live inside of the roots of
certain plants (like legumes) and can fix
nitrogen in the roots.
This is like the bacteria that live in our guts and
help us to digest food.
Legumes include peas, beans, peanuts,
soybeans, alfalfa, and clover.
So how is this a cycle? Denitrification – some
bacteria can convert nitrites back into nitrogen
gas which is released into the atmosphere
Root Nodules
Why do farmers sometimes plant
legumes and then plow them into the
ground instead of harvesting the
crop?
Crop rotation and “green manure”
The green manure is sweet clover on this Washington State
farm. Every third year clover, a legume, is planted and plowed
under. This improves the nitrogen content and physical structure
of the soil for growing wheat and corn the other two years of
the rotation cycle.
The Sitch!
You want to sell lemonade at the next CV Bucks
football game with your two and half friends, Ashton,
D. Uther Guy, and Kid Babyman.
Each of you is responsible for bringing a part of the
lemonade recipe.
Ashton brought 10 cups of sugar.
D. Uther Guy brought 20 cups of water.
Kid brought 8 lemons.
And you (because it’s so hot out) brought 100 ice
cubes!
QUESTION!
Recipe for each glass =
1 cup water
½ cup sugar
½ lemon
2 ice cubes
Your total ingredients:
20 cups H20
10 cups C6H12O6
8 lemons
100 ice
How many glasses can you sell?
Nutrient Limiting
Primary Productivity – the rate at
which organic materials are made by
producers (rate of photosynthesis)
Primary productivity depends on the
availability of nutrients (water, light
etc.)
What biomes in the world have the
highest primary productivity?
Limiting Nutrient – when a
single nutrient limits the
productivity (limits the
photosynthesis) of an entire
ecosystem
What happens if an area like a
lake suddenly receives a lot of a
limiting nutrient?
When fertilizers enter lakes, streams,
rivers, and oceans from runoff they
can supply the aquatic ecosystem with
an abundance of a limiting nutrient.
= TOO MUCH OF A GOOD THING
This excess supply of a limiting
nutrient can produce an algal
bloom. The algae reproduce
quickly because it suddenly has an
excess of nutrients. The algal
bloom can smother and kill other
forms of life.
Blooms of algae, like this outbreak of
Codium isthmocladum that washed
ashore in Florida, choke the sea grass
beds, cause oxygen depletion in the
water, and result in losses to the
recreation and tourism industries.
RED TIDES
RED TIDES
Mount Saint Helens
At 8:32 Sunday morning, May 18, 1980,
Mount St. Helens erupted.
Shaken by an earthquake measuring 5.1 on
the Richter scale, the north face of this tall
symmetrical mountain collapsed in a massive
rock debris avalanche. Nearly 230 square
miles of forest was blown over or left dead
and standing. At the same time a mushroomshaped column of ash rose thousands of feet
skyward and drifted downwind, turning day
into night as dark, gray ash fell over eastern
Washington and beyond. The eruption lasted
9 hours, but Mount St. Helens and the
surrounding landscape were dramatically
changed within moments.
BEFORE
AFTER
BEFORE
AFTER
Some weedy plants recover
quickly
Forest blown over
Same forest 9 years later
Same forest 14 years later
Changes in an Ecosystem
Ecological Succession – a series of changes in a
community over time in response to natural and
human disturbances
As changes occur, older inhabitants die out and
new organisms move in.
Primary Succession
• Occurs where there is no soil
–After a volcanic eruption
–Bare rock exposed by glaciers moving
• Pioneer Species – the first species to
populate an area (ex. lichens)
• Lichens (made up of a fungus and an
alga) can grow on bare rock.
–Lichens release chemicals that
dissolve and break down rock thus
making soil.
• Once there is soil, other organisms
come in like mosses and small plants
and animals soon follow. Why do
animals come after plants?
Secondary Succession
•Occurs when life is removed
without destroying the soil
•Plowing, fire, deforestation, drought,
etc. can all spark secondary
succession
•Occurs faster than primary
succession. Why?
Aquatic succession
• Succession can also occur in aquatic
ecosystems
– For example, when a large whale dies, the
carcass attracts scavengers and
decomposers (sharks, crabs, and
hagfishes). Smaller fishes come later after
most of the tissue has been eaten. The
decomposition of the whale makes the area
high in nutrients for marine worms and
other sediment dwellers. Lastly, bacteria
decompose the bones, which attracts
chemosynthetic bacteria, mussels, crabs,
and clams.
POPULATION BIO
…the good stuff
Characteristics of Populations
Geographic distribution – where in
an area a population lives.
Population Density - the number of
individuals of a population within a
given area
Growth rate – How fast does a
population add new members?
How do organisms arrange themselves?
(Assume they’re stationary)
Evenly distributed
Examples?
Randomly distributed
Examples?
Distribution Cont’d
Clustered or Clumped
Examples?
Methods Of Estimating Population
Size
For stationary organisms:
Quadrant method
For moving organisms:
Mark and Recapture
• Great Turtle Race
For people:
Census
Population Growth
Three factors that affect population
size:
Number of births (birthrate)
Number of deaths (death rate)
Number of individuals that leave
(emigration) or enter
(immigration) a population
Population Growth Curves
Exponential Growth – highest rate of
reproduction under ideal conditions
http://www.youtube.com/watch?v=zrx7X
g0gkQ4
Logistic growth – occurs when a
population’s growth slows or stops
following a period of exponential growth
Carrying capacity –
maximum number of
individuals in a
population that the
environment can
support
Limiting Factors
Limiting factors – conditions that cause
population growth to decrease
• Competition
• Disease (contagious)
• Predation
• Parasitism
• Lack of food, habitat, mates, and oxygen
• Climate
• And more…
Predation – hunting, killing, and eating an
animal
Example: eagles (predators) and mice (prey)
Predation may be a limiting factor for the
prey population while food availability may
be a limiting factor for the predator
60
2400
30
1200
0
0
1955
1975
Moose
1995
Wolves
Human Population
World Population as of August 2011
Estimate: 6,953,111,602
World Population as of 2050
Projection: 9,404,251,020
U.S. Population as of August 2011
Estimate: 311,906,242
One birth every...................................... 7 seconds
One death every................................... 13 second
One international migrant (net) every..... 45 seconds
Net gain of one person every................. 12 seconds
U.S. Population for 2050
Projection:422,854,000
A World Population Clock
World Clock with extra data
Source for USA and World Pop data: http://www.census.gov/ipc/www/idb/worldpopinfo.html and
www.census.gov/population/www/popclockus.html
Human Population
Industrial
Revolution
begins
Agriculture
begins
Plowing
and
irrigation
Bubonic
plague
Natural and Human Disturbances
Global Warming
Ozone depletion
Nonnative species
Invasive species
Water, soil, and air pollution
Habitat destruction (fire, deforestation, etc)
Oil spills
Salinization of soil
Mining