All living things have needs. Some of the things humans need are food, water and shelter. If we need...
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Transcript of All living things have needs. Some of the things humans need are food, water and shelter. If we need...
All living things have needs. Some of the things humans need are food, water and shelter. If we need food, we can go to a grocery store. We can get water from a faucet. We have homes that give us shelter.
All of these things are changes we have made to our environment. We need shelter, so we build houses. We need water, so we lay pipes to bring it into our homes. We need food, so we build stores and bring it all to one place.
When Europeans first came to America, there were no grocery stores. There were no houses to live in. The settlers had to grow their own food. They had to build their own houses. They changed the environment to meet their needs.
People are not the only ones who change their surroundings to meet their needs. Animals make changes, too. Beavers are a good example of animals that change their environment.
Beavers need water for protection. They also use it to get around quickly. To keep a constant supply of water, beavers often build dams on rivers and streams. These dams form lakes. The lakes provide the beavers with the water they need.
Beavers build their homes on or near the water. Some beavers build lodges right on the water. Lodges are made of mud, rocks, and wood like dams. Other beavers dig burrows in the bank near the water. Both kinds of beaver homes have underwater entrances.
Think of some other changes people or animals make to their surroundings in order to meet their needs.
ALL ORGANISMS ALSO HAVE ADAPTATIONS TO HELP THEM
SURVIVE IN THEIR ENVIRONMENT.
For example:In the animal kingdom,
the male of the species is usually “better looking”than the female of the
species.
Look at these lions.Do you know which one is
the male?
Why do you think that the male of a species is usually
“better looking” than the female in the
species?If you said it is help them
when they want to attract a mate….then you are
correct.Which peacock do you think
is the male?
Why do you think it would be best for the female to
be less colorful?The reason that the female
Cardinal is less colorful than the male is because
she is the one that protects the nest. If her color was bright, it might attract the
attention of a predator.
Let’s look at the male and female lions again.
Do you know why the female’s coloring is less
attractive?It is because she is the one
that does the hunting for the pride. Her coloring needs to be able to “blend in” with her surroundings so that her prey
will not see her before she attacks.
Plants have adaptations, too!
Look at this cactus.The leaves of a cactus are
the spines like you can see in this picture.
Why would a cactus need small, thin leaves?
Click icon to add picture
To answer this question, we would have to think about where the cactus plant usually grows.
THE DESERT!In the desert, the sun shines
almost everyday.The leaves of the cactus are
small because they don’t have to work hard to absorb sunshine to make its food, because the sun
shines so much of the time. Remember that the leaves
release water thrrough transpiration…and in the desert, the plants want to hold on to as
much water as possible.
smaller leaves = less transpiration
Now let’s talk about leaves that are found in an area that has lots of
rain, but have to struggle to get sunshine because of the taller plants that block out the sunlight.
THE RAINFOREST!!In this environment, the
leaves in the lowest level of the rainforest need big leaves so that they can
capture any sunshine that makes its way through
the taller trees that tend to block the sunlight.