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Biological Diversity
In this presentation you will:
 explore biological diversity and how it occurs
 explore why it is important to preserve
biological diversity
ClassAct SRS enabled.
Biological Diversity
I. What is Biological Diversity?
A. Biological diversity (sometimes
called biodiversity) is the variety of life
found on Earth both within and
between species and ecosystems.
B. It encompasses:
1. Species diversity – the variety
of living organisms on Earth
(plants and animals)
2. Genetic diversity – the variety of
genetic material in all living
organisms
3. Ecosystem diversity – the
variety of habitats and
communities on Earth
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Biological Diversity
II. How Does Diversity Occur?
A. There are millions of different
species of organisms on the planet.
B. The diversity of species we see
today is the product of over four
billion years of change.
C. Over many generations,
living things change into
different forms, varieties and
eventually sometimes even into
different species. This slow and
gradual process is known as
evolution.
D. Evolution has given us the
wide variety of organisms that is
the biological diversity on Earth
today.
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Biological Diversity
III. What is a Species?
A. A species is a group of
organisms that are similar in
appearance and characteristics.
They have a similar genetic makeup and are able to reproduce with
each other to produce fertile
offspring.
B. If two groups of similar
organisms would not freely
interbreed if put together, either as
a result of different mating
behaviour or incompatibility of
genetic make-up, then they are
classed as different species.
C. If groups of seemingly different organisms would breed freely if given the
chance then they are classed as subspecies.
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Biological Diversity
Question 1
What is biological diversity?
A) The variety of living organisms on Earth
B) The variety of genetic material in all living organisms
C) The variety of all habitats and communities on Earth
D) All of the above
Biological Diversity
IV. Adaptation and Natural Selection
A. To survive in a changing
environment organisms need to
adapt (change), for example, their
behavior or physical characteristics.
B. An organism with an unusual or
changed gene (a mutation) can
result in a change, for example, to
its coloring or a feature such as
the size or shape of teeth.
Siberian and Indian tiger
C. If the change benefits the organism it will survive and reproduce better
in its environment. The gene for the trait will be passed to generations that
follow (inheritance) and organisms with the trait will become more
abundant. This is known as natural selection.
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Biological Diversity
V. Adaptive Radiation
A. Adaptive radiation refers to the
creation of new species which
develop from a common ancestor.
B. This can occur when a
population of a species is
separated by a physical barrier,
for example, mountains, valleys or
rivers. This is geographical
isolation.
C. When this occurs, breeding
between the groups is totally
prevented and the two groups
evolve separately from each other.
D. They may evolve into totally separate species who
are genetically different to each other and would be
unable to successfully produce fertile offspring if
mated.
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Biological Diversity
VI. Darwin’s Finches
A. When Charles Darwin first
went to Galapagos Islands, he
noticed that the islands contained
a wider variety of finches than
Ecuador which is close by.
B. He observed 13 types of
finches. The finches were different
sizes and their beaks were quite
different from each other in shape
and size. He reasoned that each
species had evolved from a single
ancestral species, but had
adapted in different ways to
gather food in the different
habitats on the islands.
C. This is a very famous example of adaptive radiation.
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Biological Diversity
Question 2
Can adaptation to a changing environment lead to species diversity?
Answer Yes or No.
Biological Diversity
Question 3
A population of a species becomes separated into two groups by the
expansion of a valley. What is this known as?
A) Geographical separation
B) Geographical speciation
C) Geographical isolation
D) Geographical grouping
Biological Diversity
VII. Diversity of the Rainforest Ecosystem
A. The special ecosystem of the
tropical rainforest is one of the
most diverse ecosystems on the
planet. It is home to thousands of
species of animals and plants.
B. The rainforests contain a
huge proportion of the entire
world's species that is
estimated by scientists to be
between 70% and 90%.
C. It is not unusual for a square kilometer
of forest in Central or South America to
contain several hundred species of birds
and many thousands of species of
butterflies, beetles, and other insects.
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Biological Diversity
VIII. Evidence of Diversity
A. Although different species
might look dissimilar, by studying
the internal structures and
chemical processes within
organisms, scientists are able to
identify common ancestry
between many species.
B. Fossils have given us evidence
of diversity by providing evidence
of organisms that existed in the
past.
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Biological Diversity
IX. Importance of Biological Diversity
A. The variety of plant and animal
species, and the habitats in which
they live are extremely important
to humans and the way we live.
B. Plants and animals provide us
with food, shelter, clothing, and
also medicines.
C. Ecosystems are also extremely
important in keeping the chemistry
of the planet in balance and the
conditions suitable for us to
survive.
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Biological Diversity
X. Threats to Biological Diversity
A. Changes to ecosystems and
species within in them could result
in the total loss of some species
(extinction).
B. If the extinction of species
becomes greater than the
formation of new species, then
biological diversity will decrease.
C. The balance and interaction
between all living things and the
environment is so complicated
that loss of biological diversity
could ultimately put the survival of
the whole planet in danger.
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Biological Diversity
XI. Human Threats to Biological Diversity
A. One of the biggest threats to
biological diversity is human
activity. For example:
1. Humans rely on natural
resources. But by using these
resources we frequently
damage and upset the balance
of habitats. Sometimes we
destroy them completely.
2. Pollution can cause problems on
a local scale, for example by
damaging a specific habitat, or on
a global scale. For example global
warming causing the melting of
ice caps and affecting all life that
rely on them.
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Biological Diversity
B. Humans can also affect the
diversity of species by making
direct changes to the species of a
habitat. For example:
1. Activities such as selective
breeding and advances in
genetic engineering may affect
the variations of species.
2. Introducing species that are not
native to an area may cause a
decline of native species if the
new species can out-compete
the native species. For example
by having few predators or
being more resilient to disease.
The grey squirrel was introduced to
the UK and now out numbers the
British red squirrel
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Biological Diversity
XII. Preserving Biological Diversity
A. There are many reasons to preserve
biological diversity, including:
1. Health – undiscovered species
may exist that could be used as
medicines to cure diseases.
2. Recreation – many people enjoy
recreational activities such as
fishing and walking that would not
be possible if the ecosystem were
destroyed.
3. Native people – preserving
biological diversity will enable
many people to continue to live in
their native lands.
4. Right to live – many people
believe all species have the same
right to live so should be protected.
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Biological Diversity
Question 4
"The introduction of new species to a habitat could never be a cause
of reduced biological diversity." Is this statement true or false?
Answer True or False.
Biological Diversity
XIII. What Can We Do?
A. In order to preserve
biodiversity, we need to preserve
the natural environment.
B. Protecting endangered
species of plants and animals
can prevent their extinction.
C. Sustainability is an important
way of using natural resources
without damaging ecosystems.
For example, logging in the
rainforests can cause serious
damage to the forest ecosystem,
but with careful planning, it may
be possible to fell certain trees
with little impact to the ecosystem.
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Biological Diversity
Question 5
Which of the following is not considered to be a way to preserve
species diversity?
A) Sustainability
B) Protection of endangered species
C) Removal of habitats
D) Preservation of the natural environment
Biological Diversity
In this presentation you will:
 explore the need for adaptation
 explore ways in which organisms adapt
ClassAct SRS enabled.
Biological Diversity
In this presentation you will
look at the characteristics
organisms need in order to
survive long enough to
reproduce.
Eats meat
You will explore ways in which
species have, over time,
changed their structure, their
behavior and their physiology
(the function of the tissues and
cells of the organism) to
achieve this.
Eats grasses,
seeds and
aquatic plants
Eats fish
Eats berries
and seeds
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Biological Diversity
I. A Matter of Survival
A. In order for a species to
continue to exist, individuals
ultimately need to reproduce. To
be able to live long enough to do
this, they need to have survival
characteristics.
B. These include the ability to:
1. find food
2. find shelter
3. defend against predators
4. produce and rear young
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Biological Diversity
II. The Need to Change
A. The environment is always
changing.
B. Organisms must also be able
to change (adapt) in order to
survive and successfully
reproduce in the new
environmental conditions.
C. Organisms that are unable to
adapt to new conditions will either
be forced out of the habitat, or if
the number of deaths of the
species is greater than the
number of births it will become
extinct (die out).
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Biological Diversity
III. Biological Adaptation
A. Species acquire many of their
unique characteristics through a
process known as biological
adaptation.
B. This involves natural selection.
This means that certain
characteristics that are better at
helping an organism survive and
reproduce, naturally become more
frequent in the generations that
follow.
C. Biological adaptations can be
seen as physical or behavioural
changes to a species. Most
organisms have adapted both
physically and behaviourally.
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Biological Diversity
Question 1
What can happen to an organism that is unable to adapt to its
changing environment?
A) It can be forced out of a habitat
B) It may not be able to successfully reproduce
C) Survival could be more difficult and the species could
eventually become extinct
D) All of the above
Biological Diversity
Question 2
Characteristics that help an organism to survive and reproduce often
naturally become more frequent over time and through many
generations. What is this process known as?
A) Natural progression
B) Natural selection
C) Natural frequency
D) Natural reproduction
Biological Diversity
IV. Physical Adaptations - Animals
A. Physical adaptations tend to help
animals survive in their environment.
1. For example, imagine a bird that was
born with an unusually long beak. The
longer beak meant that it was easier for
that particular bird to find food.
B. The bird became stronger and
healthier. It survived longer and
reproduced more. The trait of the longer
beak was passed on to the bird's
offspring, who in turn lived longer and
reproduced more.
C. Over a long period of time, the number of
short-beaked birds reduced and there were more
long-beaked birds. This is an example of how
structural adaptation occurs by natural selection.
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Biological Diversity
D. Camouflage and mimicry are also physical adaptations that are
used to deceive predators.
E. Camouflage means that a
creature blends in with its
background to hide or look like an
inanimate or inedible object. Can you
spot the stick insect in this picture?
F. Mimicry involves a creature
looking similar to a poisonous or
bad-tasting species. The similarity
is often enough to deter
predators. Can you see the similar
colours and patterns of these two
snakes? Only the coral snake is
poisonous.
Milk snake
Coral snake
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Biological Diversity
V. Physical Adaptations - Plants
A. Plants are also adapted to
survive the conditions in which
they live.
B. In a desert where water is
scarce, many plants have thick
waxy leaves to prevent water loss.
Some are able to store water in
their stems. Others have a thin
covering of hair to shade the plant
from sunlight and prevent water
loss.
C. In a tropical rainforest, there is a
lot of water. Many rainforest plants
have "drip tips" which enable excess
water to run off. This can help
prevent the growth of bacteria and
fungi.
Drip tips
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Biological Diversity
VI. Behavioural Adaptations - Animals
A. Changes to the behavioural characteristics of an animal allow it to respond
to life needs. Examples include:
1. hibernation – some animals
have a period of deep sleep to
avoid the extreme cold of winter
months. For example, brown
bears. Their bodily functions
slow down, including slowed
breathing, reduced heart rate
and lowered temperature.
Stored fat is used up during this
period.
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Biological Diversity
B. These internal changes are known as physiological changes.
1. migration - some animals move to a
completely different area to avoid food
shortages and cold winters. Bird are the
most well known migratory animals.
They usually migrate to warmer areas
where food is easier to come by.
2. communication of danger - some
animals display particular behaviour
or alarm calls to warn others of
danger.
3. response to danger - some animals
display particular behaviour in response
to danger. For example, a lizard may
freeze and rely on camouflage to hide it
from a predator, while groups of
meerkats try to confuse predators by
bobbing their heads and creeping
towards it.
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Biological Diversity
VII. Learned or Instinctive?
A. Some behaviours that are
necessary for survival are
instinctive. This means the animal
is born with the skills to do
something.
1. when a kangaroo is born it is not
completely developed. It climbs into
the mother's pouch where it
attaches itself to a nipple for the
remainder of its development. The
kangaroo is not taught to do this. It
does it instinctively, but it is vital to
its survival.
B. Some things, however, must be learned. For example a bear
cub must learn from its mother how to hunt. Without this skill the
bear cub will not survive to adulthood.
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Biological Diversity
VIII. Behavioural Adaptations - Plants
A. Changes to the behavioural
characteristics of a plant also allow
it to respond to life needs.
B. The Northern Hemisphere
Tundra is a vast and treeless land
which is cold all year round.
C. Some of the plants that live in the
Tundra have found ways to
maximize the amount of warmth they
can get from the Sun. The arctic
poppy has dish-like flowers which
turn to follow the Sun. The dish
shape focuses the Sun’s rays to the
center of the flower keeping it warm.
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Biological Diversity
Question 3
Which of the following is an example of a behavioral adaptation that
may occur?
A) Change in body structure
B) Camouflage
C) Migration
D) Mimicry
Biological Diversity
Question 4
Which of the following is an example of a physical adaptation?
A) Seasonal migration of birds
B) Communication of danger between monkeys
C) A flower turning to face the sun
D) A desert plant having thick waxy leaves to prevent water loss
Biological Diversity
IX. Short-term and Long-term Adaptations
A. Adaptations that take a long
time and occur over successive
generations are known as
evolutionary adaptations.
B. But sometimes adaptations
occur within an organism's
lifetime.
1. The coat of the Arctic fox is
pale to blend in with the snowy
environment in the winter, but in
summer the coat darkens to blend
in with vegetation.
Winter
Summer
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Biological Diversity
X. Extinction
A. If organisms are unable to adapt to
the conditions in which they live, they
will not thrive. They may not live as
long as previous generations, and
reproduction will suffer. Individuals
may produce fewer offspring, or fewer
individuals will be able to successfully
produce offspring.
B. If the number of deaths in a
particular species remains the same
or increases while the number of
offspring surviving decreases, the
overall number of the species will
decrease. If this continues for a long
time, the species will eventually die
out and become extinct.
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Biological Diversity
C. Behavioural changes include things like migration.
In order to survive, many birds migrate to warmer
areas of the world during the harsh winter months, and
only return for the warmer, summer months.
Biological Diversity
IV. Natural Selection
A. Changes to species usually occur over many
years. The genetic makeup of an organism
can alter, perhaps as a result of a gene
mutation, and result in a change to a feature
(a trait).
B. Any trait that benefits an organism makes it
easier for it to survive than its competitors,
giving it more chance to produce and rear
young.
C. If the trait is passed to offspring, then
gradually those with the trait will become the
fittest, and increase in number compared to
those who do not possess the trait.
Biological Diversity
V. The Peppered Moth
A. The peppered moth is common in the UK and is a good
example of natural selection. The normal form of the
moth is pale and speckled, while another form is darker.
B. Originally lighter moths were most common. They were
camouflaged by the pale tree trunks they rested on. Then
during the industrial revolution, air pollution increased and
darkened the tree trunks.
C. Birds could see the lighter moths more easily on the
dark trees and picked them off and ate them. The dark
moths were camouflaged, so survived longer and
reproduced, increasing in number.
Biological Diversity
VI. Species Diversity
A. As species change and adapt to their
environments, different populations of a species
can adapt in different ways if they are exposed
to different conditions.
B. Over time, this can lead to the groups
developing very different physical or behavioural
features.
Biological Diversity
C. This can result in changes
to the genetic makeup that
are different enough to
prevent them from
interbreeding. This is then
classed as a new species and
contributes to the diversity of
life we see today.
Biological Diversity
VII. Natural Causes
A. Natural extinction of a species occurs
when the environment changes and the
adaptive characteristics of a species are
insufficient to allow its survival.
Biological Diversity
B. As the environment changes, species who
are unable to adapt, and therefore compete
for resources, will inevitably disappear. This
type of extinction is known as background
extinction.
C. Natural catastrophic events such as fires or
floods can wipe out entire habitats and many
of the life forms that the habitat supports. This
is catastrophic extinction.
Biological Diversity
VIII. Human-Made Causes
A. Human activities can also
cause extinction. Many believe
today that our activities are the
biggest threat of all to the
survival of other species.
Biological Diversity
B. As we increase in number we destroy
habitats to make space for ourselves,
destroying many species along the way.
C. We are also polluting the Earth’s
atmosphere. This is believed to be having
a devastating effect on our climate. The
rapid change to climate is endangering
many species by threatening their habitats.
Biological Diversity
IX. Introduction of Non-Native Species
A. Some species are under threat because
humans have either intentionally or
accidentally introduced other species that are
not native to the habitat. An example of this is
the Nene goose in Hawaii.
Biological Diversity
B. It was once on the brink of extinction, and this was
partly due to the introduction of mongoose by
humans to help control rats in sugar cane fields.
C. However this was not successful and the
mongoose took eggs from nesting birds, including the
Nene goose. Without young to take the place of
those who died, the numbers drastically reduced.
Today, the Nene goose is still considered
endangered, though efforts to protect it have led to
an increase in numbers.
Biological Diversity
X. Evidence of Extinction
A. Fossils are the preserved remains of living
organisms. They provide us with evidence of many
species that have existed in the past but are no longer
seen today. By studying them, we can see how
species have appeared, changed and disappeared
through time.
B. Many fossils found in older rocks are not found in
younger rocks. This is thought to show when a
species first developed and when it became extinct.
C. Fossils that appear in younger, more recently
deposited rocks are more likely to resemble species
that exist today.
Biological Diversity
Biological Diversity
Summary
After completing this presentation you should be able to:
 show knowledge and understanding of how biological adaptation
aids species survival
 show knowledge and understanding of the different types of
biological adaptations
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Biological Diversity
In this presentation you will:
 explore what causes species to become extinct
 explore how fossils provide us with evidence of extinction
ClassAct SRS enabled.
Biological Diversity
There are millions of species
of plants and animals alive
today, each of which is
adapted to survive in its
particular environment.
In this presentation you will
see what can cause a species
to become extinct (die out).
You will also look at some of
the evidence of how species
appear, change and then
become extinct.
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Biological Diversity
I. What is Extinction?
A. When the number of deaths
within a species continually
exceeds the number of births, the
population will decrease. If it
continues for a long enough
period of time, the species will die
out.
These animals are on the brink of
extinction today
B. When the last known remaining
individual of a species dies, the
species is classed as extinct.
C. Extinction is common, and
most species that have lived on
Earth are now extinct.
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Biological Diversity
II. Environmental Change
A. A species must be able to
successfully compete with other
organisms for food, water and
shelter, and protect itself from
predators in order to survive. To
continue, a species must also be
able to successfully produce and
rear young.
B. The environment is dynamic, it
is always changing. A species
must adapt (change) to new
conditions if it has any chance of
surviving long term.
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Biological Diversity
III. Adaptation
A. There are a many ways a
species may adapt over time.
These adaptations may be
physical or behavioural.
B. Physical changes include
things like changes to shape of
birds’ beaks to enable them to eat
the types of food available to
them.
C. Behavioural changes include
things like migration. In order to
survive, many birds migrate to
warmer areas of the world during
the harsh winter months, and only
return for the warmer, summer
months.
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Biological Diversity
Question 1
When is a species classed as extinct?
A) When an individual dies
B) When there is only a small number of individuals of a species left
C) When the last remaining individual of a species dies
D) When more individuals of a species are being born that are dying
Biological Diversity
IV. Natural Selection
A. Changes to species usually occur
over many years. The genetic makeup
of an organism can alter, perhaps as a
result of a gene mutation, and result in
a change to a feature (a trait).
B. Any trait that benefits an organism
makes it easier for it to survive than
its competitors, giving it more chance
to produce and rear young.
C. If the trait is passed to offspring,
then gradually those with the trait will
become the fittest, and increase in
number compared to those who do not
possess the trait.
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Biological Diversity
V. The Peppered Moth
A. The peppered moth is common
in the UK and is a good example of
natural selection. The normal form
of the moth is pale and speckled,
while another form is darker.
B. Originally lighter moths were
most common. They were
camouflaged by the pale tree
trunks they rested on. Then during
the industrial revolution, air
pollution increased and darkened
the tree trunks.
C. Birds could see the lighter moths more easily on the dark trees and
picked them off and ate them. The dark moths were camouflaged, so
survived longer and reproduced, increasing in number.
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Biological Diversity
VI. Species Diversity
A. As species change and adapt
to their environments, different
populations of a species can
adapt in different ways if they are
exposed to different conditions.
Two
species of warthog
Common
warthog
B. Over time, this can lead to the
groups developing very different
physical or behavioural features.
C. This can result in changes to the
genetic makeup that are different
enough to prevent them from
interbreeding. This is then classed
as a new species and contributes
to the diversity of life we see today.
Desert
warthog
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Biological Diversity
Question 2
"Some individuals display certain traits that improve their chances of
survival and reproduction in their environment. If the trait is genetic, it
may be passed to offspring who will also survive and reproduce, and
the number of individuals who have this trait will increase." What
process does this statement describe?
A) Extinction
B) Natural selection
C) Neither of these
Biological Diversity
VII. Natural Causes
A. Natural extinction of a species
occurs when the environment
changes and the adaptive
characteristics of a species are
insufficient to allow its survival.
B. As the environment changes,
species who are unable to adapt,
and therefore compete for
resources, will inevitably disappear.
This type of extinction is known as
background extinction.
C. Natural catastrophic events
such as fires or floods can wipe
out entire habitats and many of the
life forms that the habitat supports.
This is catastrophic extinction.
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Biological Diversity
The Dinosaurs
An example of a natural event that
caused catastrophic extinction is the
fate of the dinosaurs. There is still
debate about what actually happened
to cause the dinosaurs to become
extinct, but one popular theory is that
a meteorite struck the Earth.
The theory suggests that a meteorite
about six miles wide hit the Earth.
Apart from the obvious damage this
would do to the Earth’s surface, it
would have created a huge amount
of dust in the atmosphere.
The dust would have blocked out light needed for plant growth
so many plants would have died. Without plants to eat the
dinosaurs would have starved on a cold and dark Earth.
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Biological Diversity
VIII. Human-Made Causes
A. Human activities can also
cause extinction. Many believe
today that our activities are the
biggest threat of all to the survival
of other species.
B. As we increase in number we
destroy habitats to make space for
ourselves, destroying many species
along the way.
C. We are also polluting the Earth’s
atmosphere. This is believed to be
having a devastating effect on our
climate. The rapid change to climate
is endangering many species by
threatening their habitats.
Next >
Biological Diversity
IX. Introduction of Non-Native Species
A. Some species are under threat
because humans have either
intentionally or accidentally
introduced other species that are
not native to the habitat. An
example of this is the Nene
goose in Hawaii.
B. It was once on the brink of extinction, and this was partly due to the
introduction of mongoose by humans to help control rats in sugar cane fields.
C. However this was not successful and the mongoose took eggs from
nesting birds, including the Nene goose. Without young to take the place of
those who died, the numbers drastically reduced. Today, the Nene goose is
still considered endangered, though efforts to protect it have led to an
increase in numbers.
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Biological Diversity
The Dodo
The Dodo was a large bird that
lived on the island of Mauritius.
When Mauritius was colonized by
humans in the 1600s, Dodos were
hunted for food and their forest
habitat was damaged. Other
species like pigs, dogs, cats and
rats were introduced that ate the
Dodo's young and eggs, preventing
offspring from developing.
As the Dodo was a flightless bird it became easy prey. The Dodo was
unable to adapt quick enough to survive these changes and within eighty
years was extinct. This extinction was entirely due to the activities of
humans.
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Biological Diversity
Question 3
The type of extinction that is a natural and commonly occurring
process whereby the species that are unable to adapt and compete for
resources gradually disappear is known as...
A) ...catastrophic extinction.
B) ...common extinction.
C) ...background extinction.
D) ...foreground extinction.
Biological Diversity
X. Evidence of Extinction
A. Fossils are the preserved
remains of living organisms. They
provide us with evidence of many
species that have existed in the
past but are no longer seen today.
By studying them, we can see how
species have appeared, changed
and disappeared through time.
B. Many fossils found in older
rocks are not found in younger
rocks. This is thought to show
when a species first developed
and when it became extinct.
A few of the species known
to be extinct today
Lepidodendron
Dinosaur
C. Fossils that appear in younger, more
recently deposited rocks are more likely
to resemble species that exist today.
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Biological Diversity
Fossil Record – The Horse
The fossil record of the horse is
one of the few fossil records that
is almost complete.
Hyracotherium
The fossils come from the North
American sedimentary deposits.
This is rock formed by layers of
material that has accumulated
and hardened, forming over the
last 54 million years.
The fossils appear to show the
disappearance (extinction) of
each species of horse from the
Hyracotherium as it develops
to become the modern day
horse, Equus.
Equus
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Biological Diversity
Fossil Record – The Horse
The major changes seen in the development of the horse in this time were
related to movement and feeding. It is thought that these were adaptations
to changing conditions.
Forelimb
2
4
Height
Height
Height
Height
Height
up
about
to
up
about
5.2
3.2
to
2feet
feet
1.4 feet
up to 3.2feet
feet
2
4
54
4
2
2
3333
Oligocene.
38,000,000
Pleistocene.
Miocene.
years
26,000,000
1,000,000
ago
years
Eocene.
56,000,000
years
ago
Pliocene.
7,000,000
yearsago
ago
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Biological Diversity
Question 4
How did the introduction of animal species that were not native to
Mauritius contribute to the extinction of the Dodo?
A) They became predators of the Dodo
B) The Dodos were frightened of them so left the habitat
C) They Dodos hid from the predators so starved to death
D) The animals had no affect on the Dodos
Biological Diversity
Question 5
Fossils are used to provide us with evidence of extinct species. Which
of the following statements is true?
A) Fossils are the preserved remains of living organisms.
B) Scientists can study fossils of a species to estimate when it first
appeared.
C) Scientists can study fossils to estimate when a species became extinct.
D) All of the above statements are true.
Biological Diversity
Summary
After completing this presentation you should be able to:
 show knowledge and understanding of what causes
species to become extinct
 show knowledge and understanding of the evidence
to support extinction
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