Name:
2.8 Speciation
Target Grade:
Q1.
Fossils give us evidence for the theory of evolution.
The diagrams show how a fish became a fossil.
(a) In the sentences below, cross out the two lines which are wrong in each box.
(4)
(b) Give one way in which fossils provide evidence for the theory of evolution.
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(1)
(Total 5 marks)

Q2.
During evolution, many groups of animals have become extinct (died out).
(a) The graph shows how the number of animal groups has changed over time.
How has the number of animal groups changed between 200 million years ago and the present day?
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(1)
(b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.
Describe the different causes of the extinction of organisms.
Your description should include possible reasons for the mass extinctions shown on the graph.
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(6)
(Total 7 marks)

Q3.
The picture shows a fossil.
(a) (i) What is a fossil?
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(3)
(ii) Describe one way in which fossils are formed.
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(2)
(b) We only know about extinct animals and plants because they have left fossils.
What does the word “extinct” mean?
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(1)
(Total 6 marks)
Q4.
The drawings below show a mammoth, an extinct relation of the elephant which lived in arctic regions, and a modern elephant which lives in tropical areas.

The mammoth, which was very hairy, and the elephant, are both thought to have evolved from a scantily haired ancestor. Explain, as fully as you can, how the mammoth evolved from the common ancestor.
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(Total 5 marks)
Q5.
There is a large amount of evidence that evolution is taking place.
(a) Scientists are uncertain about how life started on Earth.
Explain why.
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(2)
(b) Salamanders are terrestrial amphibians.
The diagram shows the distribution of four different species of salamander in a country.
Originally, there was only one species of salamander in the country.
Suggest an explanation for the development of the four different species.

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(5)
(Total 7 marks)

M1.
(a) mud decayed skeleton rock
1
1
1
(b) idea that living things have changed (over time) do not allow ‘dating’ do not credit ‘evolved’ allow ‘compare the skeleton’
1
M2.
(a) increased by about 7 times / from 600 to 4300 / by 3700
(b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response.
No relevant content
There is a brief description of at least two causes of extinction, which has little clarity and detail.
There is a description of some causes of extinction, including both small-scale and large-scale events but there is a lack of clarity and detail.
There is a clear, balanced and detailed description of at least five causes of extinction, including both small-scale and large-scale events.
0 marks
Level 1 (1–2 marks)
Level 2 (3–4 marks)
Level 3 (5–6 marks)
1 examples of biology points made in the response:
• changes to the environment / named changes
• new competitors
• new diseases
• new predators
1
[5]

• volcanic eruptions
• collisions with asteroids
M3.
(a) (i) ideas that
• remains of animal/plant of specific organism
• (from) many years ago/thousands or millions of years
• found in rocks/covered by sediments for 1 mark each
Mark (a) as a whole to a total of 5 marks.
(ii) ideas that
• hard parts/bones/shells/skeletons link required
• don’t decay or
• no decay link required
• conditions needed absent/no oxygen/no water or
• parts replaced by rock mineral chemicals;
Do not accept ‘materials’ or ‘substances’.
• as they decay
Accept ‘hard’ or ‘soft’ parts for 1 mark each
(b) idea died out/none left/died off
Do not accept ‘died’ alone for 1 mark
3
[7]
2
1
[6]

M4.
natural variation in amount of body hair; in cold environment, (having genes) which produce long hair is an advantage; because hair insulates; OWTTE such animals more likely to survive; and pass these genes onto succeeding generations each for 1 mark
M5.
(a) there is a lack of valid / reliable evidence because the early organisms were soft bodied or because remains were destroyed by geological action
[5]
1
1
1
1
1
1
1
[7]
(b) populations of salamanders became isolated / separated by areas between mountains there was genetic variation in these isolated communities natural selection acted differently on these isolated communities eventually resulting in interbreeding being no longer possible and so new species have been formed