5.2
INVASION
3
a
Read the article again and answer these questions.
1
What do you think happens to the small food shop
when the supermarket starts business?
2
Is the red squirrel like the small shop or the
supermarket?
3
How did the grey squirrel come to England?
4
Do all invasive animals cause the extinction of
native animals?
5
Are there more large animal invaders than small ones?
3
b
Thinking beyond the text
Discuss these questions.
1
Why do you think the apple snail doesn’t cause
many problems in Europe?
2
What do you think are the ‘obvious reasons’ for the
fact that the amount of animal invasion is increasing?
3
Can you think of any examples of border controls?
4
Are there any problems with invasive species in
your country?
A
READING
1
Can you name the animals in the photos (A–E)
below? Have you ever seen any of these animals?
What do these animals eat?
2
a
Read the magazine article below and choose the
best summary.
1
It is about the problems that new animals face in
new environments.
2
It is about how foreign animals affect local animals
and environments.
3
It is about the similarities between the natural
environment and the business world.
2
b
Read the article again and complete this table.
Animal
Where
from?
Invaded
where?
Problem
caused?
grey squirrels
red deer
rabbits
apple snails
3
4
C
Animal invaders
How much danger are we in? How many invaders are there?
Imagine you run a small food shop in your local neighbourhood. Suddenly, a giant
supermarket opens for business opposite your shop. What happens to you and
your business?
In the natural world, things are often the same. The red squirrel was living happily
in England when, in the 1880s, many people brought grey squirrels from North
America as pets. These pets escaped into the wild and ate the same food
as the red squirrels, which means that now there aren’t many native red
squirrels in England and they are in danger of extinction.
There are many invaders that don’t cause extinctions, but they do destroy plants
and harm the economy. For example, European red deer are destroying the
forests in South America because they eat the young trees. Rabbits have
spread from Europe and now eat farmers’ crops all over the world. These kinds
of invaders cause problems for humans, unlike the grey squirrels, which
cause little damage to plants and don’t damage the economy.
Few invaders are large land animals; most of them are plants or
small animals like insects. These smaller animals often mean
farmers lose a lot of money. For example, the apple snail from
South America doesn’t cause much harm in Europe, but it causes a
lot of damage in South-East Asia because it loves to eat rice plants.
For several obvious reasons, the number of animal
invaders is increasing in every country in the world,
and many countries hope to control this situation
with, for example, strong border controls.
However, it seems impossible for us
to bring such animal invasions to a stop,
perhaps because changes are always
part of nature.
B
40
