Extinction

a. Evolution
b. Different species
c. global warming
d. change in the genotype

​What does natural selection lead to?

What is a mutation?
a. A change in the DNA
b. A change in the cell
C. Natural Selection

Do Now in your exercise book

Tuesday 10th October Extinction

Fill in the Blanks

What can cause extinction

What is extinction?

Extinction occurs when all organisms of a species dies out. This may be because the organisms were not able to adapt to changing conditions fast enough.

For other reasons e.g humans hunting, destroying habitats and global warming

Extinction can be

It usually takes place in many generations.

A slow process

Evolution is .......

Multiple Choice

Evolution is a

• Slow process

• Quick process

• takes place in one generation

• is caused by a disaster

Use the link and do the activities in the webpage

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E
n
g
a
g
e

Sort these organisms

into those that are

extinct and those that

are endangered.

The Northern White
Rhinoceros – Extinct,
last one died in 2018

Spix macaw - Extinct

Pinta Island
Tortoise –
Extinct, last one
died in 2015

Dodo – Extinct, last one
seen in 1660’s

Giant panda- Endangered

Tiger - Endangered

Asian elephant - Endangered

Dinosaurs - Extinct

https://www.stem.org.uk/rx3
3e4

What made the dodos

become extinct?
Explore

The dodo only lived on one island - Mauritius. When

sailors arrived in the sixteenth century they found that the
dodo was very easy to catch, and even though it didn't

taste very nice, many were eaten.

The dodo's natural habitat was almost completely

destroyed after people started settling on Mauritius. And

when pigs, cats and monkeys were introduced, they

added to the problem by eating the dodo and its eggs.

The last confirmed sighting of a dodo was in 1681 and by

the end of the 17th century there were no dodos left.

Some species are labelled as endangered,
which means a small population of them
still live in the world, and are in danger of
becoming extinct.

Why is maintaining biodiversity

important?
Extend

High biodiversity

Low biodiversity

Ecosystems with higher biodiversity are more stable as they

can easily adjust to changes.

We are slowly realising that the future of our species on Earth

depends on maintaining high biodiversity. Biodiversity is

important for human wellbeing as it provides food, potential

foods, industrial materials and new medicines.

„By conservation- which means...

„protecting an organism’s natural habitat,

„to increase their chances of survival

„To reduce the disruption of food chain and

„Leads to discovering new species.

„By conservation- which means

Breeding animals under human controlled environment
so that they can :

„Create a stable and healthy population of a species

„Gradually lead them to the natural habitat

„Problems:

„Maintenance can be difficult

„Animals produced may not adapt in the wild

Gene Banks: (seed bank, tissue bank, pollen bank,
cryobank )

Gene Banks: (seed bank, tissue bank, pollen bank,
cryobank )

„Store genetic samples of different species

To produce new individuals in future
Store genetic samples of different species

Task

Multiple Choice

According to most scientists, what is the ultimate cause of most mass extinctions?

• overhunting

• evolution of new species to replace old ones

• major change in environment

• asteroid impact

Multiple Choice

Which of these describes a species that has become extinct?

• fewer members of the species are dying than being born
• more members of the species are dying than being born
• very few members of a species are alive
• all members of a species have died

Multiple Choice

Which of the following species is extinct?

• woolly mammoth
• giant panda
• bald eagle
• green sea turtle

Multiple Choice

Which of the following is NOT a reason a species may become extinct?

• competition
• reproducing
• habitat loss
• overhunting

Multiple Choice

Suppose a pond dries up. What will most likely happen to the fish that lived there?

• They will learn to live on land.
• They will move to another pond.
• They will learn to breathe air.
• They will not survive.

Multiple Choice

True or False? Many scientists think that an asteroid caused the dinosaurs to go extinct.

• True

• False

Multiple Choice

Species that are in danger of becoming extinct are called __________.

• endangered

• not lucky

• extinct

• in a jam

Multiple Choice

When a plant or animal becomes extinct, it is gone _______.

• forever

• until next week

• for 5 years

• to sleep

Multiple Choice

Evidence of an animal or plant that lived a long time ago on Earth is called a ________.

• fossil

• tiger

• extinct

• endangered

Multiple Choice

A ______________ species is on its way to becoming endangered or extinct.

• threatened

• cuddly

• sleeping

• fossil

Multiple Choice

Humans are causing extiction in which ways?

• By over hunting animals for food or products.
• By destroying the natural habitat of species.
• By polluting the environments of the world.
• All of the above.

Multiple Choice

What is a mass extinction?

• When all the species in a particular area on earth suddenly go extinct
• When multiple species from all over the earth suddenly go extinct 
• When one species goes extinct due to habitat changes
• When all life on earth is wiped out 

Multiple Select

Choose all that apply. Fossils are great clues to life in the past. However, they have limitations. Some of those limitations are:

• We have fossils for only 1% of species believed to have lived.

• They are fragile and break easy loosing any evidence we have.

• They do not show us internal structures.

• They are too deep in the Earth to find.

Multiple Choice

 Which is LEAST LIKELY to push a species toward extinction?  
         

• a.   Cutting down entire forest 
• b.  Putting animals in a zoo 
•  c.   Polluting mountain streams 
• d.   Introducing new species to an ecosystem with no known natural predator