Download Ecosystems – Adaptation and survival:

Ecosystems – Adaptation and Survival:
Student Study Guide
Lesson Text
Vocabulary
Adaptation - Any feature that helps a living thing to survive in its environment.
Behavior - An action that a living thing makes in response to its environment.
Hibernation - An inactive, sleeplike state that animals may enter in the winter.
Migration - The movement of animals to new locations at certain times of the year.
Mimicry - An adaptation in which one living thing imitates or mimics another.
Protective coloration - An adaptation in which the color of a living thing helps it to
blend in with its surroundings.
Protective resemblance - An adaptation in which both the color and the shape of a
living thing helps it to blend in with its surroundings.
Warning coloration - An adaptation in which color warns predators that the animal is
unpleasant or dangerous.
Introduction
Living things must struggle to survive. Many animals are in constant danger of being
eaten. Hunting animals must compete for limited supplies of food. Even plants must find
ways to avoid being eaten.
Over time, living things have developed characteristics that help them to survive and
reproduce. These characteristics are called adaptations. Scientists study adaptations to
learn how living things compete and survive.
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Main Idea Check
Q. What do you call a characteristic that helps a living thing survive and reproduce?
A. A characteristic that helps a living thing survive and reproduce is called an
adaptation.
Adaptation
Any characteristic that helps a living thing survive and reproduce is called an adaptation.
Adaptations include physical characteristics. For example, the fur of a polar bear enables
it to survive in cold climates. The waxy coating of a cactus helps it to prevent water loss
in hot, dry climates.
For animals, adaptations also may include behaviors. For instance, wolves hunt in
packs. Wolf packs can take larger prey than individual wolves, helping the wolves to
survive.
Living things with successful adaptations tend to produce more offspring. These
offspring will inherit the same adaptations. Over many generations, successful
adaptations may spread to all members of a species.
Main Idea Check
Q. True or false? Adaptations can include both physical characteristics and behaviors.
A. True. Adaptations include physical characteristics, such as the warm fur of a polar
bear, and behaviors, such as wolves hunting in packs.
Plant Adaptations
Nearly all plants share certain adaptations, such as roots that soak up water. Other
adaptations are found only in certain groups of plants.
Many plants have developed adaptations to survive in a particular climate. For example,
many trees in colder climates shed their leaves in the fall. This adaptation helps prevent
water loss.
Other adaptations help plants to reproduce. For instance, flowering plants produce
flowers with sweet nectar to attract bees and other animals. This adaptation helps them
to spread pollen and reproduce. Plants such as ferns and pine trees do not produce
flowers.
Other adaptations help plants avoid being eaten. For example, milkweed produces
chemicals that are poisonous to most animals.
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Main Idea Check
Q. Fill in the blank. Shedding leaves in the fall is an example of an _____ found in
plants.
A. Shedding leaves in the fall is an adaptation. It helps plants survive the winter.
Animal Adaptations
Animals have a great variety of adaptations. Bats, birds, and insects have wings that
enable them to fly. Whales have smooth skin and can hold their breath for a long time.
These adaptations help them to survive in the water.
Some adaptations enable animals to survive in a particular climate. For example, seals
have a thick layer of fat beneath the skin that keeps them warm in the cold.
Many animal adaptations involve hunting and escaping. Octopuses spray clouds of ink to
escape hunting animals. Gazelles can run quickly to escape.
Hunting animals have their own adaptations. Anteaters have long tongues to help them
catch ants. Tigers have sharp claws and teeth that enable them to catch prey.
Main Idea Check
Q. Bats, birds, and insects share what adaptation?
A. Wings. Wings are physical characteristics that help these animals survive and
reproduce.
Adaptations in Behavior
Animals also may have adaptations in behavior. Like wolves, lions hunt in groups. This
adaptation helps them to catch prey. Similarly, zebras travel in herds. Fish form groups
called schools. Traveling in numbers helps these creatures to escape hunting animals.
Many animals are active at night to avoid hunters or the heat of the sun. Animals may
dig burrows for the same reasons.
Other adaptations in behavior help animals to survive changing seasons. Many birds and
other animals travel long distances to find food and avoid harsh winters. This behavior is
called migration.
Animals such as bats, frogs, and snakes enter a period of inactivity during the winter.
This behavior is called hibernation.
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Main Idea Check
Q. Fill in the blank. Hunting in groups is an example of an adaptation in the _____ of
wolves.
A. Hunting in groups is an example of an adaptation in the behavior of wolves. It helps
wolves survive and reproduce.
Review of Adaptations
Remember that any characteristic that helps a living thing survive and reproduce is
called an adaptation. Animals, plants, and all other living things have adaptations.
Adaptations can include physical characteristics. For example, tigers have sharp claws
and teeth that help them to catch prey.
For animals, adaptations also may include behaviors. For example, many birds migrate
long distances. This behavior helps birds to find food and avoid harsh winters.
Main Idea Check
Q. True or false? A tiger’s claws and the migration of birds are both physical
characteristics.
A. False. A tiger’s claws are a physical adaptation. But the migration of birds is an
adaptation in behavior.
Protective Coloration
The appearance of many living things helps them to avoid being eaten. When this kind
of adaptation involves color, it is called protective coloration.
Many animals have coloration that helps them to blend in with their surroundings. For
example, insects that live on plants are often green. Insects that live on tree bark are
often brown.
Some animals can change their coloration with the seasons. For instance, birds called
ptarmigans have white feathers in the winter to blend in with snow. In the summer, the
ptarmigan’s feathers are reddish-brown to blend in with plants on the ground.
Main Idea Check
Q. Fill in the blank. The ptarmigan grows white feathers in the winter to provide
________.
A. The ptarmigan grows white feathers in the winter to provide protective coloration.
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Protective Resemblance
Some living things have both the color and the shape of objects in their surroundings.
This kind of adaptation is called protective resemblance.
Protective resemblance is especially common among insects. For example, stick insects
have both the color and shape of sticks. A stick insect that does not move is difficult to
distinguish from a twig.
Other animals also have protective resemblance. For instance, certain pipefish have both
the color and shape of sea grass. A pipefish hiding in a bed of sea grass is hard to spot.
Main Idea Check
Q. Why do stick insects have the color and shape of sticks?
A. The color and shape of stick insects help them blend in with their surroundings. This
is an example of protective resemblance.
Warning Coloration
Some animals do not attempt to hide at all. Instead, these animals may be brightly
colored. These bright colors are a warning that the animal is unpleasant or dangerous.
This kind of adaptation is called warning coloration.
Often, warning coloration shows that an animal tastes bad or is poisonous. For example,
the skin of many frogs and salamanders is poisonous. These animals are often bright
red, orange, yellow, or even blue.
Warning coloration also can signal that an animal is dangerous. For example, the yellow
and black stripes of many bees and wasps warns that these insects have dangerous
stingers.
Main Idea Check
Q. True or false? The yellow and black stripes of many bees and wasps are a warning to
other animals.
A. True. The yellow and black stripes are an example of warning coloration.
Mimicry
Some living things have developed adaptations that help them to resemble other living
things. This kind of adaptation is called mimicry.
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Mimicry works in various ways. In some cases, a harmless animal may mimic a
dangerous one. For example, the color patterns of harmless king snakes closely
resemble those of deadly coral snakes. Other animals may confuse the two species,
helping the king snake to survive.
Some dangerous or unpleasant animals mimic each other. For example, many bees and
wasps have black and yellow stripes. An animal that is stung by one insect with these
stripes may avoid other species with similar markings.
Main Idea Check
Q. Fill in the blank. The harmless king snake looks much like the deadly coral snake.
This is an example of ______.
A. The harmless king snake looks much like the deadly coral snake. This is an example
of mimicry.
Summary
Any characteristic that helps a living thing survive and reproduce is called an adaptation.
For animals, adaptations also may include behaviors.
Living things have a variety of adaptations that help them to hide. When these
adaptations involve color, they are called protective coloration. Some living things
resemble not only the color but also the shape of objects in their surroundings. This kind
of adaptation is called protective resemblance.
Some living things have bright colors. These bright colors are often a warning that the
animal is unpleasant or dangerous. This kind of adaptation is called warning coloration.
Other living things have adaptations that cause them to resemble one another. This kind
of adaptation is called mimicry.