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Can cloning save species?
Teachers’ Notes
What it’s about
Scientists have recently created a cloned dog, and there is now the potential to clone most
mammal species. So is cloning a viable way of resurrecting species that are close to extinction?
This activity focuses on the consequences of species failing to reproduce in the wild, and even in
captivity. Without getting into the details of cloning, students weigh up arguments and decide
whether or not cloning can be effective in preventing species’ extinction.
Where it fits
Science: QCA 5b: life cycles
 If living things did not reproduce, they would eventually die out
 Identify one or two species facing extinction and describe a programme which tries to
overcome the problem, for example captive breeding or – the focus of this activity – cloning to
try to save species that fail to breed even in captivity.
 That adults have young and that these grow into adults which in turn produce young
Literacy: Year 5 term 3, text level
In the optional part of the activity, students will draft and write an e-mail to put a point of view and
comment on an emotive issue.
What students will learn

That reproduction is important to the survival of the species.
Students will consider arguments for and against cloning in the context of using the
technology to save species from extinction. Through so doing they will recognize that
conventional reproduction is the best way to ensure the survival of species, but that cloning
could, in some cases, be a viable option.
What you need to do
Introducing the activity
 Display slide 2 of the PowerPoint, in slideshow mode. It introduces the latest news about
cloning. Tell students that cloning means creating an almost identical animal, perhaps a
replacement pet.

Ask students whether they would clone their favourite dog when it dies (if they had the money
– it costs about £20, 000!). Invite initial opinions – yes/no and why. Compare a ‘hands up’
poll to the results of the BBC Newsround vote, in which 34% of respondents voted ‘yes’ to the
question ‘would you like a cloned pet’, and 66% voted ‘no’.

Tell students that perhaps cloning pets isn’t the best thing we could do with the powerful new
technology. Maybe we could use it to save endangered species.

Display slide 3. Ask students to suggest reasons for the dramatic decline of ape numbers.
There are clues in the other graph, which shows the enormous increase in the number of
humans. Humans have removed most of the habitats available to apes and other
endangered species.
Leading the main activity

Set the task: Tell students that some animal species may soon be extinct: gone forever.
Some people have suggested that cloning technology could protect endangered species that
cannot breed, even in captivity. In fact, the first clone of an endangered animal – a gaur (wild
ox) called Noah – was born in 2001. Ask the students: ‘can cloning help to protect
endangered species? You will do an activity to help you come to a reasoned opinion and –
if you wish – communicate it to others’.

Read through the opinions on slide 4. Ask students to organize the arguments for and
against cloning as a way of saving species. The activity is designed to be a drag and drop
using a project or interactive whiteboard. Students put the speech bubble arguments on slide
5 into the grid. They can leave behind any views that they consider are neither for nor
against cloning.
Ask students to categorize the arguments as strong or weak by dragging the strong and weak
icons into the grid.

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The activity can also be done by printing out the arguments and the grid on slide 7 onto a
worksheet.

(Optional). Display slide 6. Ask students to complete the e-mail to tell the environmental
organization about their views on using cloning to save species.
Possible answers to the argument activity
YES
STRONGEST ARGUMENTS
Cloning can protect animals from extinction so
people will always be able to see these
beautiful creatures
Some endangered animals, like chimps, cannot
breed in captivity. Cloning may be their last
hope.
WEAKER ARGUMENTS
Cloning can boost a species’ population before
we release animals into the wild.
NO
STRONGEST ARGUMENTS
Cloning animals does not solve the problem of
habitat loss.
Now, cloning technology is unreliable. But it
will improve.
Cloned animals are all the same, so they might
all get the same disease.
Cloning is expensive. It is better to spend
money on protecting animals in the wild.
WEAKER ARGUMENTS
Cloned animals may breed less well than their
wild relatives.
Science at your fingertips
What is cloning?
Cloning is the creation of genetically identical individuals through asexual reproduction. In the
cloning process the DNA of one individual is "copied" into a cell or embryo of another. The
embryo develops in the mother’s uterus until birth. By definition, cloning refers to the copying of
one individual to make another.
How easy is cloning?
For every 100 eggs that are fused with host cells, only about 20 produce the first step on the
cellular level, known as blastocysts. Only a tiny fraction of these lead to live births.
Another problem is that clones need mothers! Very few conservationists advocate rounding up
wild female endangered animals for that purpose or subjecting a precious zoo resident of the
same species to the rigors of assisted reproduction and surrogate motherhood. That means that
to clone an endangered species, researchers must solve the problem of how to get cells from two
different species to yield the clone of one.
Have endangered species already been cloned?
Yes, the gaur, in 2001. Gaur numbers dwindled to about 36,000 because they were hunted by
humans and because the forests, bamboo jungles and grasslands in India and Southeast Asia
where they live have become degraded. Some researchers believe cloning may offer the only
way to save such species from extinction. And the particular circumstances of Noah's cloning
suggest that animals that have recently gone extinct could be brought back into existence.
How can we prepare for cloning endangered species?
Scientists are building DNA "banks" where tissue and other sources of genetic and reproductive
material from endangered species are archived. Many scientists believe that this ‘rescued’ and
preserved DNA could be used to produce clones. The potential results of cloning are enormous,
and could seriously help to preserve the Earth’s biodiversity by cloning endangered species such
as gorillas and tigers.
What is captive breeding?
Efforts to save endangered species also include captive breeding. Animals bred in captivity are
later released in the wild to restore or add to a breeding population (a population of individuals
capable of reproducing). Captive breeding programmes have already led to increases in the
known populations of California condors, whooping cranes and perigrene falcons.
What are the problems of using captive breeding and cloning to try to save endangered
species?
Such breeding may reduce the genetic diversity of a species and its ability to survive in the wild.
No clones of endangered species have yet been returned to the wild. Also, captive-bred animals
are also more likely to carry disease, which they may transmit to the wild population. Captive
breeding and cloning programmes are very expensive and offer only short-term solutions that
may divert attention from finding solutions to the original causes of a species’ decline, such as
habitat destruction or toxic pollution.
Why are so many animals endangered?
There are many causes of the current extinction crisis, most stemming from humans’
unsustainable management of the planet. The causes include:



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habitat destruction
deterioration of habitat quality through overgrazing, selective logging and burning
the spread of alien and invasive species, which may replace native species through
predation, competition or disease
over-harvesting of valuable plants and animals, for timber, pets, food and so on
Could we bring back extinct animals, mammoths, even dinosaurs, like in Jurassic Park?
We could possibly bring back animals that had recently become extinct, if samples of their DNA
had been preserved. Dinosaurs? No. DNA only survives for 10 000 years, and dinosaurs
disappeared 65 million years ago. Mammoths are still only a theoretical possibility, and not
possible with today’s technology – but in the future, who knows?
Web links
Cloned mammals have bred naturally for the first time, scientists have revealed:
Endangered African wildcat clones have given birth to two litters, a total of eight kittens in all,
confirming the expectation that cloning could one day help animals that are threatened with
extinction. http://www.telegraphindia.com/1050831/asp/atleisure/story_5178261.asp
Page of simple information on reasons animals are endangered
http://64.233.183.104/search?q=cache:L4eEvtnQ68J:www.zoobooks.com/newFrontPage/animals/animalFacts/endangeredanimals.html+%
22captive+breeding%22+encyclopedia&hl=en
BBC newsround explanation of the cloning of the dog
http://news.bbc.co.uk/cbbcnews/hi/newsid_4740000/newsid_4743800/4743835.stm#graphic
Clone your favourite old cat here – for £20,000! Cloned dogs are coming soon.
www.savingsandclone.com
Good source of arguments for and against cloning endangered species
http://www.hhmi.org/cgibin/askascientist/highlight.pl?kw=&file=answers%2Fgeneral%2Fans_035.html
nice image of endangered monkey dreaming about cloning
http://www.primatecare.com/cloning.htm