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VA SOL 4.5
The student will investigate and understand how plants and animals in an
ecosystem interact with one another and the nonliving
environment. Key concepts include:
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behavioral and structural adaptations;
organization of communities;
flow of energy through food webs;
habitats and niches;
life cycles; and
influence of human activity on ecosystems.
What is the main difference
between plants and animals?
• Animals are living
organisms. This means
they breathe, eat, grow,
and reproduce.
• Plants are living things too,
so what is the biggest
difference between plants
and animals?
• Plants produce (make)
their own food and
animals feed off other
things.
http://www.wallpaper.net.au/wallpaper/animals/Tree%20Frog%20-%201024x768.jpg
Animal Adaptations
• In order for animals to be able to survive,
they need to be able to adapt (change).
• An adaptation is a trait that makes an
animal suited to its environment.
• Anything that helps an organism survive in its
environment is an adaptation. It also refers
to the ability of living things to adjust to
different conditions within their
environments.
http://www.indyzoo.com/uploadedimages/Scarlet%20macaw3.jpg
•There are two main categories of adaptations:
structural or behavioral.
Structural Adaptations
A structural adaptation
involves some part of an
animal's body, such as
the size or shape of the
teeth, the animal's body
covering, or the way the
animal moves.
Examples:
• Teeth - since different
animals eat different things,
they don't all have the same
kind of teeth
• Body coverings - Hair,
scales, spines, and feathers
grow from the skin. All of
these parts help animals
survive in their
environments.
• Movement - animals find
food by moving from place to
place
Echolocation in
bats is an adaptation
for catching insects.
http://www.deskpicture.com/DPs/Nature/Animals/GreatWhite_1.html
Structural Adaptation Ex:
Camouflage allow an animal to blend
into its environment and makes it hard
for enemies to single out individuals.
Camouflage –
Structural Adaptation
A completely different approach for
deception is camouflage, whereby animals
seek to look inanimate or inedible to avoid
detection by predators and prey. There are
many examples of rainforest species which
are cryptically colored to match their
surroundings. For example, the Uroplatus
geckos of Madagascar are incredible masters
of disguise and are practically unnoticeable
to the passer-by.
An even more amazing group is the
katydids, a group of grasshopper-like insects
found worldwide. Katydids are nocturnal
insects which use their cryptic coloration to
remain unnoticed during the day when they
are inactive. They remain perfectly still, often
in a position that makes them blend in even
better. Katydids have evolved to the point
where their body coloring and shape
matches leaves—including half-eaten leaves,
dying leaves, and leaves with bird
droppings—sticks, twigs, and tree bark.
Other well-known camouflage artists include
beetles, mantids, caterpillars, moths, snakes,
lizards, and frogs.
Structural Adaptation Ex:
Mimicry allows one animal to look, sound, or
act like another animal to fool predators into
thinking it is poisonous or dangerous.
Hawk Moth Mimicry
This moth caterpillar defends itself by mimicking a snake.
Animals that use mimicry use colors and markings to look like another animal.
Blue poison dart frog
Mantella madagascariensis
Behavioral Adaptations
Behavior adaptations include activities that help an
animal survive. Behavior adaptations can be learned or
instinctive. (a behavior an animal is born with).
Examples: Social Behavior, Behavior for Protection, Migration
Social behavior some animals live by
themselves, while
other live in groups.
Ex: Penguins live in large
communities to help keep warm.
Behavior for protection - An
animal's behavior sometimes
helps to protect the animal.
•For instance the opossum plays dead.
•A rabbit freezes when it thinks it has been seen.
Behavioral Adaptations
Migration-is the behavioral
adaptation that involves an
animal or group of animals
moving from one region to
another and then back again.
Animals migrate for different reasons:
• better climate & food
• safe place to live & raise young
• go back to the place they were born.
Food Chains
All living things depend on one another to survive. A food chain consists of organisms that depend
on each other as food sources. A food web is made up of many food chains within a natural
community of all the organisms in an area. Many animals eat more than one thing and each link is
important to the entire food web system. Food chains are made up of four main parts:
1. The sun is the
energy provider
for everything
on earth.
2. Producers include all
green plants and use
the energy of the sun to
make their own food.
Plants make up the bulk
of all food chains and
provide oxygen to all
living things.
3. Consumers include every organism
that eats something else. Consumers
are either herbivores (plant-eaters),
carnivores (meat- and plant-eaters),
omnivores (meat- and plant eaters),
parasites (living off other organisms), or
scavengers (animals that eat dead
animal carcasses).
4. Decomposers (bacteria
and fungi) convert dead
matter into gases such as
carbon and nitrogen that
are released back into the
air, water or earth.
The organization of communities is
based on using energy from the sun
within a given ecosystem.
*The greatest amount of energy in
a community is in the
producers.
Within a community, organisms
are dependent on the
survival of other organisms.
Energy is passed from one
organism to another.
The sun’s energy cycles through
ecosystems from producers
through consumers and back
into the nutrient pool
through decomposers.
Food chains and food
webs are simplified ways
of looking at the way
energy flows among living
organisms.
It all starts with the sun, which
provides the energy that sustains all
life on earth.
Green plants, such as grass
and duckweed, convert the sun's
energy and nutrients from the soil or
water into plant material.
Herbivores (plant eaters), such
as mice and minnows, eat plant
materials an convert his stored
energy into animal tissue.
Carnivores (meat eaters), such
as hawks and bass, eat the smaller
animals and transfer the energy once
again.
When carnivores die,
specialized organisms called
decomposers convert this tissue
back into soil nutrients that are again
used by the green plants at the
beginning of the chain.
Living organisms in an ecosystem depend on each other for food and
essential nutrients such as carbon and nitrogen. This interdependence
often takes the form of a feeding relationship - ie, they eat each other!
Make sure you understand the meaning of the following terms:
Producers
ie, green plants. All food chains start with them, because they can
make food by photosynthesis
Primary
consumers
feed primarily on plant material. They are herbivores - eg rabbits,
caterpillars, cows, sheep, and deer.
Secondary
consumers
feed primarily on animal material. They are carnivores - eg cats, dogs
and lions.
Omnivores
eat both plants and animals - eg bears and humans.
Predators
kill for food. They are either secondary or tertiary consumers - eg
polar bears, golden eagles.
Prey
are the organisms that predators feed on. Examples of predator and
prey species are: fox and rabbit; and caterpillar; wolf and lamb.
Scavengers
feed on dead animals . They perform a useful cleaning-up function.
Examples are crow, vulture, buzzard and hyena.
Decomposers
feed on dead and decaying organisms and on the undigested parts of
plant and animal matter. (They do not 'eat' the food like scavengers,
as they have no mouth-parts. Instead they break down solid matter
into liquids which they can absorb.)
Examples: bacteria and some fungus
A food chain shows
who eats what in a
particular habitat.
For example: grass
seed is eaten by a
vole, which is eaten
by a barn owl. The
arrows between
each item in the
chain always point
in the direction of
energy flow - in
other words, from
the food to the
feeder.
*All food ultimately comes from green plants
or producers. The other organisms in the
food chain are consumers, because they all
get their energy and biomass by consuming
(eating) other organisms.
*All food chains are pretty short. There are
never more than four steps, because a lot of
energy is lost at each step, and after three
steps most of the available energy has been
expended. This also explains why the
organisms at the top of food chains (eg owls)
are very small in number compared with
those lower down (eg grass plants). After 2
steps there is simply not enough available
energy to support more than a few top
predators.
*In its natural habitat it is
unusual for an animal to eat
only one particular
organism, so a more realistic
way of showing feeding
relationships is to draw a
series of interconnecting
food chains. This is called a
food web.
*This food web describes
feeding relationships in a
freshwater pond ecosystem.
* It allows you to follow the
routes that biomass (and
energy) take through the
system.
Pondweed (a producer) is eaten by the
mayfly nymphs, which are in turn fed upon
by both the dragonfly nymphs and the
brown trout. The brown trout make a meal
of the dragonfly nymphs too.
The other producer in this web is the
microscopic algae. This is eaten by the
freshwater shrimp. The shrimps are fed
upon by dragon fly nymphs and brown trout
(which also eat the dragonfly nymphs).
The Riddle of the Niches
Can you fill in the missing words?
(When it’s the last word in a line, it will rhyme with the line above.)
I’m a producer. I’m a cool dude.
I can take sunshine and turn it into ___________.
I am a consumer, yes I am.
I eat __________ whenever I can.
I am a scavenger, that’s important to you,
‘Cause I eat ___________ stuff, pew, pew, pew.
I’m a decomposer, I am royal,
‘Cause I break things down in the ____________.
These are niches, roles for all,
If one of these is missing, the ecosystem will ________.
I am a human being and I understand,
That I should live and care for this ____________.
Habitat
- The place where
an organism lives. A habitat is
often thought of as the
organism's address.
Examples: A lion’s habitat is a
savanna. A monkey’s habitat
is a rain forest. A cactus’s
habitat is in the desert.
A niche (from the French
word meaning “nest”) is
the function an organism
performs in the food web of
that community.
No two types of organisms
occupy the exact same niche
in a community!
Niche - An organism’s way
of life. A niche is considered to
be an organism’s occupation.
Examples: A lion’s niche
includes where and how it
finds shelter and food, when
and how often it reproduces,
how it relates to other
animals, etc.
FOOD CHAIN & HUMAN INTERACTION
How have humans affected
the food chain?
When we spray pesticides, we put
the food chain in danger. By
breaking one link on the chain means
all of the organisms above that link
are in threat of extinction (like the
domino effect). By hunting animals
nearly to extinction, everything
above the animal in the food chain is
put in danger. A 'chain reaction' in
the food chain can be
perilous! Since the food chain
provides energy that all living things
must have in order to survive, it is
imperative that we protect it.
Habitat is any place on the earth
that contains everything an animal needs
to survive and reproduce. This includes
obvious things like food, water, air, and
shelter, but it may also include many
other factors such as temperature,
rainfall, and soil type.
Each animal is equipped to live its life
under certain conditions (the same can be
said for plants). For instance,
woodpeckers need dead and dying trees
that provide insects to eat and soft wood
for drilling nest cavities. Meadowlarks live
and nest on the ground in open, grassy
areas. You will not find a woodpecker
perched on a fence post in the open
prairie, nor will you see a meadowlark
peeking out from a nest cavity in the
deep woods. The habitat just isn’t right
for them.
Habitat loss is probably the
greatest single problem facing
wildlife today. As a habitat is
destroyed or altered by human
activities, wildlife species are
forced to find new areas of
habitat, adapt to life in different
types of habitat, or die. Some
species are able to adapt; some
become extinct.
Wildlife conservation is directly
linked with habitat conservation.
If habitat is available, wildlife will
be there. By conserving, restoring,
and creating habitat, we ensure
that a variety and abundance of
wildlife have places to call home.
http://www.nhptv.org/natureworks/nwep.htm
SUGGESTED VIDEO CLIPS:
•#1 – Adaptation
•#2-Coloration
•#5-Habitat
•#9-Wildlife Web 1
•#14 –Niche