Transcript Adapting to the Environment

Unit 6 - Change Over Time
Adapting to the Environment
Adaptation - a behavior or physical characteristic that
allow an organism to survive or reproduce in its
environment.
Environmental Adaptations
15.
Behavioral Adaptations
9. Can individual organisms adapt behaviorally? If so, what
can cause these changes?
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Yes! A Behavioral Adaptation is something an animal
does - how it acts - usually in response to some type of
external stimulus.
◦ Whales migrate to follow the food supply.
◦ Bears hibernate when food sources are depleted (less) each
winter.
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Examples of Some Adaptions
Adaptations
What is the adaptation?
What is this adaptation?
16. Fitness - an organism’s ability to survive and
produce offspring.
10. Traits that support successful survival and reproduction in
a new environment become _________________ , while
those that don’t become _______________ .
Plants and animals adapt and change as they
respond to their surroundings.
1. What environmental pressures would cause an organism to adapt
or change?
Drought, loss of habitat, temperature change, flood, volcanic eruption, ?
Other examples?
2. Can environmental pressures favor one trait in a species over
another?
◦ Yes, amount of fur vs beak size for temperature change.
◦ Other examples?
3. How could that effect a species over time?
◦ Fur may become thicker with colder weather.
◦ Other examples?
Many factors influence how organisms change
over time.
4. What are the factors that can cause a species to
change over time?
• Usually the habitat has changed for some
reason.
Abiotic? Weather, water amount, temperature
Biotic? Lack of prey, disease,
5. How do those factors cause changes?
Think about your answers to #2 and #3. What
examples can you add based on the factors
from above?
Traits in a Population
6. What might lead to the predominance (greater in
number) of certain traits in a population?
A change that caused some organisms to survive and
reproduce. More fitness!
7. What might lead to the suppression (reduction) of
certain traits in a population?
A change that causes some organisms to die off and
not be able to reproduce. Less fitness!
Adapting to the Environment
11. Natural Selection – a process that makes an organism
better suited to its environment that becomes common
over successive generations in that species
◦ These organisms tend to survive and produce offspring
◦ Offspring inherit these characteristics and pass them on to
their offspring over many generations.
◦ Poorly suited characteristics may disappear in the same way.
Human Influence on Traits
8. What are some methods humans use to influence certain
characteristics of organisms?
Artificial Selection (12) – The breeding of plants and animals
to produce desirable traits. Organisms with the desired traits,
such as size or taste, are artificially mated or crosspollinated with organisms with similar desired traits.
Corn has been artificially selected or bred to have
more kernels, larger kernels and longer cobs.
Human Influence on Traits
Selective Breeding (13) – Same as Artificial Selection.
Choosing parent organisms with certain traits so that those
traits will be passed on to the next generation. Ex., sweet
corn, square watermelons, traits in dogs or racing horses,
etc.
Brain Break
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FORWARD and BACKWARD CIRCLES
1. Point your arms toward the ceiling.
2. Keep your elbow straight and move your right
arm forward creating a large circle. Continue
making forward circles with this arm. Now do the
same with your other arm except
go BACKWARD. Continue with both arms moving
at the same time. Make sure you have this pattern
working before you continue.
3. While both arms continue to move, lift your right
foot off the ground and make a ninety degree angle
with your knee. Hold this for a few seconds.
4. Now extend your right knee out to make your
leg parallel to the ground. Hold for a few seconds.
5. Stop.
6. Repeat the same process again with your left leg.
Cloning

Taking DNA from one organism and inserting it into the
egg of another organism. This egg is then implanted into a
third organism.
 Dolly the sheep
 Strawberries
 Food products
Human Influence on Traits
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Genetic Manipulation (also
known as genetic engineering)
(14) – Transferring a gene from
the DNA of one organism into
another in order to produce a
desired trait. Ex., cloning,
golden rice, insecticide in corn,
glow in the dark cats, etc.
Artificial Selection
Because artificial selection lacks the control of fitness
needed to increase fitness, artificial selection can cause
problem traits to predominate in a species.
 For example, Dobermans are a breed of dog that has been
bred for a certain appearance. In the process of selecting for
this appearance, a genetic defect has increased in frequency
in the population.
 This defect causes narcolepsy, a condition that causes these
dogs to uncontrollably fall into deep sleep. Clearly, this
condition does not increase the animal's fitness and would
be strongly selected against by natural selection.
 However, since these animals have been subjected
to artificial rather than natural selection for
generations, the defect has spread in the population.
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Artificial Selection vs Natural Selection
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The process of domestication is called artificial selection.
Like natural selection, artificial selection acts by allowing
differential reproductive success to individuals with different
genetically determined traits in order to increase the
frequency of desirable traits in the population.
However, unlike naturally selected traits, artificially selected
traits do not necessarily convey greater fitness.
Instead, artificially selected traits are based on what the
person breeding the plants and animals desires. These traits,
which can range from longer cobs in corn plants to a
particular coat color in dogs, are selected for by allowing
only individuals that possess the trait to reproduce, while
those that lack the trait are prevented from reproducing.
Predation

Predation is the interaction in which one organism kills
another organism for food.
◦ Predator - the organism that kills
◦ Prey - the organism being killed
Predator and Prey Effects
The effects of predator/prey will change constantly.
 Look at the graph on page 725 looking at wolves and
moose populations.
 Predators have adaptations that help them hunt more
effectively.
 Prey have adaptations that help them avoid attack. See
page 727.
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Strategies For Animal Survival 1 Animal Video Clip