Transcript Food Chains - Beckwith`s Science Spree

Organization of
Life
Biosphere
Ecosystems
Communities
Populations
Organisms
What is an
ecosystem?
• An ecosystem is all the animals and the
plants in a habitat, together with their
environment.
• An ecosystem provides everything that the
animals and plants that live there need.
ecosystem - all the living and
nonliving things
that interact in an area
Levels of Organization
in an Ecosystem
Organism
Population
Community
Ecosystem
Biotic Vs. Abiotic
Factors
What things are included in an
ecosystem?
• Living
– Biotic factors
• Things that are
living
• Bio=life
• Biology=study of life
– Examples:
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Humans
Dogs
Trees
Flowers
Bacteria
• Nonliving
– Abiotic factors
• Things that are NOT
living
• A=NOT
• Bio=life
– Examples:
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Rocks
Oxygen (O2)
Sunlight
Water
Carbon dioxide (CO2)
Biotic Factors
Abiotic Factors
SKY
SUNLIGHT
WIND
Water
SAND
Chapter 19, Section 2 (pages 512-515):
Cycles in Nature
Ecological Succession:
Objectives:
- to learn about the development of communities by succession
- to learn the difference between primary and secondary
succession (and some organisms characteristic of each
process)
- to examine the gradual formation of a mature community
Ecological
Succession
succession – the
replacement of one type
of community with
another of a single place
over a period of time
Ecological
Succession
A gradual development of a community
over time, such as the regrowth of a
forest after a fire, is called succession
– 1. primary succession
– 2. secondary succession
– 3. mature communities (and
biodiversity)
Ecological Succession
1. Primary Succession – occurs in an area where
other organisms
had not previously lived
– No soil, just bare rocks
– Over a very long time, a series of organisms live
and die on the
rock = primary succession
– The first organisms to live in this area are called
pioneer species
Ecological
Succession
Secondary Succession - A
2.
change in the community in
which new populations of
organisms gradually replace
existing ones
– It occurs in an area where an existing
community is partially damaged
Ecological
Succession
Ecological
Succession
3. Climax Community – a community
that is stable and has a great
diversity of organisms
- it is also called a mature community
Explore the World
Around You!
Adapted from Mrs. Kirkpatrick
What is a
Habitat?
• A habitat is a place where a particular
animal or plant species lives.
• An artificial habitat is a manmade place.
• The ecological role of the organism in
its habitat is called its niche.
Which habitats do you
recognize?
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Desert
Rain Forest
Tundra
Prairie
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Grassland
Forest
Marine
Zoo
Describe the characteristics of Earth's major terrestrial biomes (tropical rain forest, savannah, temperate, desert,
taiga, tundra and mountain) and aquatic communities (freshwater, estuaries and marine) (GPS, ITBS)
(7SC_B2005‐12)
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12a ‐ give examples of adaptations organisms have which make them suited to life in specific biomes
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12a1 ‐ describe the climate and other abiotic and biotic factors of major biomes
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assess how changes in environmental conditions can affect the survival of both individuals and entire species and
cause them to become endangered or extinct (GPS, ITBS, CE) (7SC_B2005‐13)
What are Biomes?
A biome is one of Earth’s large
ecosystems…
Biomes are regions in the world that share
similar plant structures, plant spacing,
animals, and climate (= weather =
precipitation + temperatures).
We know…
• There are many ecosystems on the Earth
• There are many different species on the Earth
• Species adapt to fit their ecosystem
…but why?
How are Biomes Classified?
Biomes are classified as either terrestrial (land)
or aquatic (water). Terrestrial comes from the
Latin word terrestris which means earth.
Aqua means water; aquatic refers to
freshwater, marine and estuary ecosystems.
How Many Biomes Are There?
Scientists disagree over the exact number of
biomes, but in general they include around
8-10 biomes.
climate – long-term prevailing weather
conditions in a particular area
The sun’s warming effect on the
atmosphere, land, and water establishes
the temperature variations, cycles of air
movement, seasonal variation, and
evaporation of water, that are responsible
for dramatic latitudinal variations in climate
How are biomes formed?
Biomes are distributed across the Earth based on climate.
Therefore, in areas that are far apart, you will sometimes find
similar plants and animals because the climate is similar.
Biomes usually found at cold latitudes far from the
equator are sometimes also found on high mountains
at low latitudes. Typically, a climb of 100 feet in
elevation is equivalent to traveling 600 miles
northward. Typically, the farther you move north or
south of the equator, the colder the temperature gets.
Another factor affecting climate is elevation. The
higher you go in elevation, the colder the temperature
gets.
Climates of the World
• There are 3 major climate zones that
cover the world.
–Polar, temperate, and tropical
In the zone
• Within each zone, there are
a variety of biomes which
support various ecosystems.
–A biome is a large region
characterized by a specific
type of climate and the
plants and animals that live
The tropical
zone
• Also known as the tropics, this is
the warmest zone located around
the equator.
• The tropical zone extends from
23.5° S to 23.5° N
–The tropical zone includes the
following biomes:
•Tropical rain forests
The temperate
zone
• This is the area between the tropical zone and
the polar zone.
• This zone occurs from 23.5°N to 66.5°N and
23.5°S to 66.5°S
• Temperatures here tend to be moderate (in the
middle).
– The United States sits in the temperate zone.
– The temperate zone includes the following
biomes:
• Temperate forests
• Temperate grasslands
• Temperate deserts
The polar zone
•These zones surround the poles of the
Earth. They have the coldest average
temperatures.
•This zone extends from 66.5°N to 90°N and
66.5°S to 90°S
–The polar zone includes the following biomes:
–Tundras
–Taigas
You are responsible for
studying the following biomes:
Earth’s Major Terrestrial Biomes:
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Tropical rain forest
Savanna
Temperate forests
Desert
Taiga
Tundra
Mountain
You are responsible for
studying the following biomes:
Earth’s Major Aquatic Communities:
• Freshwater
• Estuaries
• Marine
Great EssayCharacteristics
of Biomes:
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Rainfall + Temperature = Climate
Physical features
Geographical locations
Types of Animals
Types of Plants (vegetation/producers)
Forests
• Covers 1/3 of the Earth’s area
• Dominated by trees and woody
vegetation
• Precipitation - distributed evenly
throughout the year
Temperate
Deciduous
Forest
• Moderate
climate
• Temperature – varies throughout the year
(seasonal); ranges between -30oC and 30oC
• Precipitation - even throughout the year;;
averages from 75 to 150cm
• Soil - rich with decayed matter
• Flora - Plants consist of broad leave trees;
most trees will lose their leaves in the winter;
well-developed understory
• Fauna - squirrels, rabbits, deer, skunks, and
Deciduous
Forest
You can find deciduous
forests in Eastern America,
Southern tip of South
America, Western Europe,
eastern China, & East
Australia.
A forest biome
with many kinds
of trees that
lose their
leaves each
autumn
• The average
temperature in our biome
is about 50 degrees F.
• The average
precipitation is about 3060 inches per year.
Animals of the Deciduous
Forest
• Wolves, deer, bears, and a
wide variety of small mammals,
birds, amphibians, reptiles, and
insects
Polar Boreal/Taiga or
Coniferous Forest
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Also known as Taiga, or Coniferous Forest
The largest terrestrial biome
Typically found between 45o and 60o North latitude
Temperature – Low temperatures, cold climate with summer rains
Precipitation - Snow is the primary form of precipitation (40 – 100
cm annually)
• Soil – nutrient-poor, acidic
• Flora – mostly conifers such as pine, spruce and fir trees; limited
understory
• Fauna – Animals include woodpeckers, hawks, moose, bears, lynx,
but very few reptiles
Animals of the Taiga
• Rodents, snowshoe hares, lynx,
sables, ermine, caribou, bears,
wolves, birds in summer
Tropical
Rainforest
Tropical
Rainforest
• Location = typically found near the equator
• Precipitation = receives more than 200cm of rain
annually
• Temperature = typically between 20oC and 25oC for
the entire year
• Highest biodiversity = as many as 50% of all the
world’s animal species may be found here
Rain Forest
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The Rain Forest is made of 3 layers
The first layer is the canopy
The second layer is the understory
The third is the forest floor
Animals of the Tropical
Rain Forest
• More species of insects, reptiles,
and amphibians than any place
else; monkeys, other small and
large mammals, including in some
places elephants, all sorts of
colorful birds
Chaparral
Chaparral
• Location - found between 32o and
40o latitude
on the west coast of continents
• Precipitation - receives between 35
and 70cm
of rain, usually in the winter
• Extremely resistant to drought and
Earth’s Biomes (whole
page)
Climate Zone
Biome Name
Avg. Temp
Precipitation
Soil type
Plants
Animals
Temperate Grassland
(prairie, steppes, pampas,
savannas)
• Temperatures vary summer to winter
• Moderate rain fall
• Seasonal drought and occasional
fires
• Typical animal life includes jack
rabbits, deer, foxes, coyotes, birds,
and many other species
Grassland
Grassland
• A biome where grasses, not
trees, are the main plant life.
Prairies are one kind of
grassland region.
Prairie, Steppes, Pampas,
Savannas
• Temperature: Summer temperatures can reach up to
38oC, and winter temperatures can fall to –40oC; varies
summer to winter
• Precipitation: moderate rain fall = usually receives
between 50 and 90cm of rainfall each year
• Seasonal drought and occasional fires
• Fauna: typical animal life includes jack rabbits, deer,
foxes, coyotes, birds, and many other species
• Flora: Because of the dry climate, trees are found only
near water sources such as streams
There are two types of grasslands. The tropical grasslands
(savannah) and the temperate grasslands.
– Dominated by grasses
– savannah has a wet and dry season
– Temperate grassland has a hot summer and cold
Grassland animals
• American Grasslands: Prairie
dogs, foxes, small mammals,
snakes, insects, various birds
Tropical Savanna
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Warm/hot climates
Major vegetation is grass
Dry and rainy seasons
Seasonal fires help maintain balance
The savanna is home to various
reptiles, rodents, birds, and large
mammals such as elephants, lions,
tigers, giraffes and zebras
Tropical
Savanna
• Experience a wet and dry season
• Temperatures: Hot
• Precipitation: Annual rainfall is between 50 and
127cm
• Flora: Grasslands with a few scattered trees
• Fauna: More species of grazing mammals than
any other biome
Tropical
Savanna
Desert
• A sandy or rocky biome, with
little precipitation and little plant
life
Desert
Desert
• Location – Typically found between 25o and
40o latitude
• Precipitation – Little rain = receives less than
25 cm (10 inches) of rain each year; very dry
air, arid
• Temperature - typically ranges between 20oC
and 25oC but some extreme deserts can reach
temperatures higher than 38oC and lower than
–15oC; high daytime temperatures, low
evening temperatures
• Lots of wind
Animals of the Desert
• Rodents, snakes, lizards, tortoises,
insects, and some birds. The Sahara
Desert in Africa is home to camels,
gazelles, antelopes, small foxes, snakes,
lizards, and gerbils
Tundra
• A cold biome of the far north;
the ground is frozen even in
summer
Tundra
Tundra
• Treeless or marshy plain; very cold; low
diversity; simple vegetation; short
growing season (6-8 weeks)
• Permafrost – permanently frozen soil
starting as high as a few centimeters
below the surface – which severely limits
plant growth
• Temperature - Winter temperatures
average –34oC
Summer temperatures usually
average below 10oC
• Precipitation - Low precipitation (15–25 cm
per year) but ground is usually wet
because of low evaporation;
Animals of the Tundra
• Musk oxen, migrating caribou,
arctic foxes, weasels, snowshoe
hares, owls, hawks, various
rodents, seals, walruses,
occasional polar bear
Marine Biome
• Water covers nearly 75% of the Earth’s surface
• There are numerous species of plants and animals who live
here.
• These range in size from microscopic organisms to the size of a
100 ft whale.
• Consists of oceans, coral reefs, and estuaries
• The ocean is the largest of all ecosystems.
• The ocean contains a diverse array of plants and animals at
various depth zones.
• Coral reefs consist mainly of coral.
• Estuaries are areas where fresh and salt water environments
converge. Mangroves, oysters, crabs and marsh grasses are
examples of species in this environment.
Freshwater Biomes
• Includes ponds, and lakes; streams and rivers, and
wetlands
• Ponds and lakes have well lit zones and a variety of
fish dominate this zone.
• Streams and rivers move in one direction.
• Wetlands are areas of standing water that support
aquatic plants.
ENGAGE
• Listen to the sounds in the El Yunque
Rainforest in Puerto Rico. This is the only
rainforest in the U.S. and its territories.
http://www.hear.org/alienspeciesinhawaii/sp
ecies/frogs/index.html#frogcalls
EXPLORE
• Complete the “Biome Box Activity.”
EXPLAIN
1. List major biomes of the world.
2. How does the climate of a biome affect
the flora and fauna of the region?
3. List unique characteristics of biomes.
EVALUATE
In your journal, list 5 biomes describing at
least 3 characteristics for each of the 5
biomes. Describe how different
environments support different varieties of
organisms.
• Protect the wonderful world around you!
• Remember each habitat is a unique
place where plants and animals make
their home.
• What makes your habitat unique?
Types of
Interactions
Population Ecology:
Interactions within the
Environment
1. Limiting factors
2. Carrying capacity
Limits on Population Growth
• Limiting factors slow the population growth
rate down.
• Population growth levels off at a carrying
capacity—the largest population size of a
given species an environment can hold.
Population Size
Number of individuals present at a given time
The passenger pigeon was once North America’s
most numerous bird, but is now extinct.
Population Density
Number of individuals per unit area
In the 19th century, the flocks of passenger
pigeons showed high population density.
Population Distribution
Habitat arrangement of individuals
Interactions
between
Organisms:
1.
2.
3.
4.
Competition
Predators and Prey
Symbiosis
Coevolution
Interactions between Organisms:
1. Competition:
When 2 or more
individuals of a single species
interact with one another.
Example: a group of rabbits
feeding in the same area
Interactions
between
Organisms:
1.
2.
3.
4.
Competition
Predators and Prey
Symbiosis
Coevolution
Interactions between Organisms:
2. Predators and Prey:
All Living Organisms in a Community
are Dependent upon Each Other
• Predators: are organisms that kill
and consume animals
Animals that eat other animals are called predators.
Some animals are predators and prey.
This means they eat some animals but are eaten by
others.
Animals that are eaten by other animals are called prey.
Some prey animals are herbivores.
Some omnivores and carnivores are also prey to other animals.
Predator–prey cycles
Population dynamics of predator–prey systems
sometimes show paired cycles: ups and downs
in one, drive ups and downs in the other.
Interactions between Organisms:
Predators and Prey
Predator Adaptations:
To survive, predators must be able to
catch their prey.
Predators have a wide variety of
methods and abilities for doing so.
Interactions between Organisms:
Predators and Prey
Prey Adaptations:
Prey have their own methods and
abilities to keep from being eaten.
Example: Prey are able to run away
from predators.
Interactions between Organisms:
Predators and Prey
Prey Adaptations:
More Examples:
1. Camouflage
2. Mimicry
3. Defensive Chemicals
4. Warning Coloration
toad
Adapted from Ms. Weinberg
Interactions between Organisms:
Predators and Prey
Prey Adaptations:
1. Camouflage – blending in with the
background
Polar Bear
• Has white fur for camouflage.
• Each hair is hollow for extra
insulation.
• Has sharp teeth and claws to
catch and eat prey.
• Has ridged foot pads to
prevent slipping.
Wow! This insect looks exactly
like its background.
Protective Coloration
• Coloration and protective
resemblance allow an
animal to blend into its
environment.
• Another word for this might
be camouflage.
• Their camouflage makes it
hard for enemies to single
out individuals.
This alligator is doing a good job of hiding.
Would it be camouflaged to its background
if it had a bright pink body?
Camouflage
• Camouflage Many animals have the
means of blending into their natural
background for protection.
• The fur of some small animals of
northern countries turns white in
winter, to blend with the snow. The fur
of these animals is brown in summer, to
enable them to hide from enemies in
woods or brush.
This owl looks like the rocks that
surround it.
Are these lips or
a leaf?
-A moth on a
tree trunk
Eyed-Hawk moth; looks like the eyes of a hawk
so other animals will not want to eat him.
Animals need to adapt to their environments or
they get eaten.
More Camouflage
Interactions between Organisms:
Predators and Prey
Prey Adaptations:
2. Mimicry – adapt to look like
something dangerous like a predator
Mimicry
• Mimicry allows one
animal to look, sound, or
act like another animal to
fool predators into
thinking it is poisonous
or dangerous.
Physical adaptation
Mimicry
= looking or sounding like another living organism
The Viceroy butterfly uses mimicry to look like the Monarch butterfly.
Can you tell them apart?
I’m the
Viceroy!
Poisonous
I’m the
Monarch!
More Mimicry
Hawk Moth
Mimicry
• This moth
caterpillar
defends itself by
mimicking a
snake.
Tiger Swallowtail Butterfly
larva or caterpillar, showing
eyespots and somewhat
humanlike face, USA.
Physical
adaptations
are body structures that
allow an animal to find
and consume food,
defend itself, and to
reproduce its species.
Physical
adaptations
© A. Weinberg
help an animal
survive in its
environment.
Interactions between Organisms:
Predators and Prey
Prey Adaptations:
3. Defensive Chemicals – having deadly
toxins in or on itself
Any predator that eats, or tries to eat,
one of these animals will likely die
(or at least get a really bad stomachache).
Physical adaptation
Chemical defenses (like venom, ink,
sprays)
Interactions between Organisms:
Predators and Prey
Prey Adaptations:
4. Warning Coloration – animals that
have a chemical defense need a way
to warn predators that they should
look elsewhere for a meal…so they
have adapted warning colors and
patterns.
Interactions
between
Organisms:
1.
2.
3.
4.
Competition
Predators and Prey
Symbiosis
Coevolution
Interactions between Organisms:
3. Symbiosis -
a close relationship
in which two different organisms live
in close association with each other
Examples: mutualism, commensalism,
and parasitism
Three Types of Symbiosis
• Parasitism-parasite obtains food
directly from other living organisms
– Leech
• Commensalism-one organism benefits
while the other is largely unaffected
– Remora and shark
• Mutualism-a relationship that benefits
both
– Algae/coral reef
Symbiosis
Parasitism – a relationship in which
one organism benefits (parasite)
and the other is harmed (host)
–The parasite obtains food directly
from other living organisms.
• Examples: ticks on a dog,
•
leeches
Three Types of Symbiosis
Commensalism – a relationship in which one
organism benefits and the other is not affected
Example: barnacles on a whale, remoras on a
shark
Symbiosis
– Mutualism – a relationship in which both organisms
benefit from each other
• Example: birds eating pest off a rhino’s back,
algae in a coral reef
Symbiosis – “living together”
Relationship
Species A
Species B
Commensalism
+
0
Mutualism
+
+
Parasitism
+
-
Interactions
between
Organisms:
1.
2.
3.
4.
Competition
Predators and Prey
Symbiosis
Coevolution
Interactions between Organisms:
4. Coevolution:
the evolution of
two species that is due to mutual
influence, often in a way that makes
the relationship more beneficial to
both species
Examples: ants and acacia trees ,
pollinators and flowers
Animals and plants
• Most plants and animals are specially
adapted to survive in a particular habitat.
• They have developed special features to
suit the demands of their environment.
• This is called adaptation.
Some more examples
of adaptation...
All birds have similar
characteristics.
But many water
birds have features
that are different
from those birds live
on land.
Webbed
feet for
swimming
Long legs are good for wading
These wings act as flippers
Some animals are
camouflaged to blend in
with their surroundings.
This lion blends in well
with the grassy
background.
This keeps them safe as it
is more difficult for other
animals to see them or
catch them for food.
These zebra could
easily be mistaken
for bushes from
a distance.
This lizards skin is so
similar to the rock
colour.
Aquatic animals have
streamlined bodies
to move more easliy
in the water.
Camels store water in their
humps.
Snakes glide across the hot
sands and can shed their skin
These animals have
adapted to live in
the hot climate of
the desert.
Ostriches have
long eyelashes to
keep out the sand.
These animals have
adapted to be more
suited to cold
temperatures.
Polar bears are kept warm by
their body fat.
Deer have a
warm layer
of fur.
Layers of fat keep the
seals body warm, and small
ears stop heat loss.
Even plants have
adapted to their
habitats.
The cactus has fleshy stems
that store water.
Dandelions seeds are
easily dispersed.
The water provides support for this lily
as it has less developed roots to hold it
in place.
Animals and plants help each other
Plants and animals depend on each
other for a wide variety of things.
Protection
Nests to reproduce
Food
Shelter
Gas exchange
Credits
• North Gwinnett Middle School – 7th Grade
Science Teachers: Karen Troncalli Wise, Rena
Beckwith, Tom Manning, et al.
• Text:
– http://www.physicalgeography.net/fundamentals/9k.html
– http://www.ucmp.berkeley.edu/glossary/gloss5/biome/index.html
• Pictures:
– http://www.worldbiomes.com/
– http://www.ucmp.berkeley.edu/glossary/gloss5/biome/index.html
– http://www.blueplanetbiomes.org/
• PowerPoint:
– Arizona Game and Fish Department, 2005
– NGMS 7th Grade Science Teachers
Desert
• Animals are small
• Many animals are nocturnal
• Temperatures can be very hot
or very cold
• Plants are adapted to conserve