1.	What is evolution?
A.	A measure of the relative survival and reproductive success of an individual
B.	A cumulative change in the genetically controlled characteristics of a population
C.	A physical change during an organism’s life that is inherited by its offspring
D.	A random change in the proportions of alleles from generation to generation 
(Total 1 mark)

2.	Which of the following represent homologous features?
A.	Wings in birds and insects
B.	The appendix in humans and horses
C.	Fins in fish and wings in birds
D.	The striped coat of the zebra and the tiger
(Total 1 mark)

3.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Describe what is meant by a food chain using an example with four named organisms.
(4)
(b)	Outline how global warming may affect arctic ecosystems.
(5)
(c)	Explain how natural selection can lead to evolution using antibiotic resistance in bacteria as an example.
(9)
(Total 20 marks)

4.	Populations of threespine sticklebacks (Gasterosteus sp.), a fish living in small freshwater lakes in British Columbia, Canada, are derived from the marine threespine stickleback (Gasterosteus aculeatus). In order to investigate the process of speciation in these populations, three small lakes were studied. Each lake contained two varieties of stickleback: a large, bottom-dwelling variety that fed on invertebrates near the shore and a small, plankton-eating variety that lived in the open water. The probability of breeding between pairs of individuals was measured under laboratory conditions in the following breeding combinations:
I	different varieties (small × large) from the same lake
II	different varieties from different lakes
III	same variety (small × small) and (large × large) from different lakes
IV	same variety from the same lake.
 
	The data are summarized below.
		
	[Source: Science by MOSES KING, Reproduced with permission of AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE in the format Journal via Copyright Clearance Centre]
 
(a)	Identify the highest and lowest probabilities of breeding for individuals of the same variety from different lakes.
Highest probability: ....................................................................................................
Lowest probability: .....................................................................................................
(1)

(b)	Identify the breeding combination that results in the lowest probability of breeding.
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(1)
 
(c)	Analyse the probability of breeding between individuals from the same lake.
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(2)
 
(d)	Scientists concluded that speciation is taking place in these populations. Discuss the evidence for speciation provided by the data.
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(3)
(Total 7 marks)

5.	The spontaneous origin of life on Earth is thought to have involved the non-living synthesis of simple organic molecules.
(a)	List two other processes needed for the spontaneous origin of life.
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(2)
 
(b)	Discuss possible locations where conditions would have allowed the synthesis of organic compounds.
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(2)
 
(c)	Outline the role of prokaryotes in the development of an oxygen-rich atmosphere on the Earth.
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(2)
(Total 6 marks)

6.	Fossils provide important evidence for evolution.
(a)	Outline how radioisotopes can be used to date fossils.
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(2)

(b)	The half-life of the radioisotope 14C is approximately 5730 years.
	
	Using the decay curve shown above, deduce the age of a fossil that contains 30% of the original amount of 14C.
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(1)

(c)	Describe two major trends that can be seen from fossil remains in the sequence Ardipithecus ramidus, Australopithecus species and Homo species.
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(2)
(Total 5 marks)

7.	Common guillemots (Uria aalge) are large sea birds of the auk family. They breed in colonies at high densities but make no nest. Their single egg is incubated on bare rock. Alloparenting behaviour is frequently observed, where non-breeding birds will take care of other chicks. Scientists fitted electronic time-depth recorders onto twelve common guillemots and recorded five different activities during the chick-rearing period: at the colony, in flight, resting or active on the sea surface and diving. The pie charts below include pooled data from all birds showing overall time budget and time budget at sea.

[Source: The Journal of Experimental Biology: jeb@biologists.org.]
 
(a)	State which activity takes up least of the overall time budget of the guillemots.
......................................................................................................................................
(1)

(b)	Calculate the percentage of the overall time budget the guillemots spend resting on the sea surface.

............................................ %
(1)
 
(c)	Outline the activity of guillemots at sea.
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(2)
 
(d)	Suggest two reasons, other than breeding, why birds spend more time at the colony than any other activity.
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(2)
(Total 6 marks)

8.	Competition between genetically similar species of birds may lead to changes of one or more characteristics. One characteristic that results from this kind of selection is differences in the beaks. Researchers studied the beak lengths of two species of warblers. The graphs below show the beak lengths of Pine Warblers (Dendroica pinus) and Yellow-throated Warblers (Dendroica dominica) from three geographically isolated areas in the USA.

	[Source: R Ficken et al. 1968. Evolution. Vol 27. Pp 307–314. Republished with the permission of Wiley-Blackwell.]
 
(a)	(i)	Identify the species with the shortest mean beak length.
...........................................................................................................................
(1)

(ii)	Determine the difference in the mean beak length of the two populations of Yellow-throated Warblers in Midwest and Delmarva.
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(1)
 
(iii)	Compare the range of variation in beak length of the Yellow-throated Warblers in Midwest to the beak length of the Yellow-throated Warblers in Delmarva.
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(1)
 
(b)	Suggest an advantage for the longer beaks of Yellow-throated Warblers in Delmarva.
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(1)

(c)	Using the Yellow-throated Warbler as an example, outline the concept of allopatric speciation.
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(3)
(Total 7 marks)

9.	Discuss the incompleteness of the fossil record and the resulting uncertainties about human evolution.
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(Total 6 marks)

10.	Triarthus was a trilobite that lived on Earth about 500 million years ago. The diagrams below show its structure, viewed from above and below. The structure was discovered by studying fossils of Triarthus.
		
[Source: R Fortrey, (2000), Trilobite!, page 62]
 
(a)	There are many animals living on Earth today that belong to the same phylum as the trilobites, but there are no living trilobites. Deduce, with a reason, the phylum to which Triarthus belonged.
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(2)

(b)	Outline the evidence for evolution provided by fossils.
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(2)
 
(c)	Some trilobites swam in clear, shallow water and had very large eyes. Suggest how species with large eyes could evolve from species with smaller eyes.
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(2)
(Total 6 marks)

11.	(a)	Define the term clade.
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(1)

(b)	Distinguish between analogous and homologous structures, giving an example of each.
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(2)
 
(c)	The table below lists five animals along with four morphological characteristics. A plus sign (+) indicates that the animal has this characteristic while a minus sign (–) indicates that the characteristic is absent.

Animal	Jaws	Limbs	Hair	Placenta	
Salamander	+	+	–	–	
Mouse	+	+	+	+	
Jellyfish	–	–	–	–	
Koala	+	+	+	–	
Salmon	+	–	–	–	
	Based on the features above, a student constructed a cladogram. State the names of the organisms missing in the following cladogram.

(2)

(d)	Describe the major anatomical features that define humans as primates.
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(2)
(Total 7 marks)

12.	Discuss the endosymbiotic theory for the origin of eukaryotes.
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(Total 6 marks)

13.	A study was undertaken of the evolution of two species of wasps, one the parasite of the other. The parasite queen, Vespula squamosa, kills the host queen, Vespula maculifrons, and takes over her role in the colony. Data was compiled for 13 colonies of V. squamosa and 37 colonies of V. maculifrons to analyse the genetic structure of the two species.
	Each point on the graphs represents the genetic distance and geographic distance between a pair of colonies. The genetic distance indicates the number of differences in specific DNA markers between a pair of colonies. The results are shown below.

	[Source: Hoffman EA, Kovacs JL, Goodisman MAD. 2008. “Genetic structure and breeding system in a social wasp and its social parasite.” BMC Evolutionary Biology. Vol 8. P 239. © 2008 Hoffman et al; licensee BioMed Central Ltd.]
 
(a)	(i)	Determine the greatest genetic distance between any pair of colonies of V. squamosa.
...........................................................................................................................
(1)
 
(ii)	Identify the greatest geographic distance between any pair of colonies of V. maculifrons.
...........................................................................................................................
(1)
 
(b)	Describe the relationship between the geographic distance and genetic distance in the two species.
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(1)
 
(c)	Compare the two species in terms of genetic distance between the pairs of colonies.
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(2)

(d)	Data collected on eight specific alleles in the two species indicated that each species was in Hardy–Weinberg equilibrium. Evaluate all the data regarding possible evolutionary changes within the two species.
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(2)
(Total 7 marks)

14.	(a)	(i)	Distinguish between transient polymorphism and balanced polymorphism.
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(2)

(ii)	State an example of transient polymorphism.
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(1)
 
(b)	Describe an example of a barrier between gene pools.
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(2)

(c)	Outline how variations in DNA can indicate phylogeny.
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(2)
(Total 7 marks)

15.	Which of the following are used as evidence for evolution?
I.	Homologous structures
II.	Selective breeding of domesticated animals
III.	Overproduction of offspring
A.	I and II only
B.	I and III only
C.	II and III only
D.	I, II and III
(Total 1 mark)

16.	Drosophila subobscura (shown in photograph below) is a species of fruit fly native to Europe.
The sample on the left is from Spain, latitude 39°, and the one on the right is from Denmark, latitude 56°. The species was introduced into both South America and North America approximately 20 years ago. The graph below shows the wing size in arbitrary units of D. subobscura at different latitudes in the three locations.

[Reprinted from Mark Vellend, Luke J Harmon, Julie L Lockwood, Margaret M Mayfield, A Randall Hughes, John P Wares and Dov F Sax. 2007. “Effects of exotic species on evolutionary diversification”. Trends in Ecology and Evolution. Vol 22, issue 9. Pp 481–488. Copyright (2007), with permission from Elsevier.]

(a)	Identify the relationship between wing size and latitude shown by D. subobscura in Europe.
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(1)

(b)	(i)	Compare the data for wing size of D. subobscura in North and South America with wing size in Europe.
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(2)
 
(ii)	Suggest one reason for the differences.
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(1)
 
(c)	Predict, with a reason, what might happen to D. subobscura in the future as a result of its introduction to new areas.
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(2)
(Total 6 marks)

17.	(a)	State two processes needed for the spontaneous origin of life on Earth.
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(2)
 
(b)	Outline the properties of RNA that may have allowed it to play a role in the origin of life.
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(2)
(Total 4 marks)

18.	(a)	Outline a method for dating fossils using 14C.
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(2)
 
(b)	Outline the trends illustrated by the fossils of Ardipithecus and Australopithecus.
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(3)
(Total 5 marks)

19.	Compare convergent and divergent evolution.

Convergent evolution	Divergent evolution	

		
(Total 3 marks)

20.	(a)	Outline the process of adaptive radiation.
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(3)

(b)	There has been a change of thinking; moving from gradualism to punctuated equilibrium demonstrates the changing nature of science. Discuss these two ideas about the pace of evolution.
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(4)
(Total 7 marks)

21.	(a)	Outline, using named hominid fossil species, trends in hominid skull evolution.
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(3)
 
(b)	Discuss the correlation between diet and brain size.
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(2)
(Total 5 marks)

22.	Which of the following are used as evidence for evolution?
I.	Homologous structures
II.	Selective breeding of domesticated animals
III.	Overproduction of offspring
A.	I and II only
B.	I and III only
C.	II and III only
D.	I, II and III
(Total 1 mark)

23.	(a)	Outline the properties of RNA that may have allowed it to play a role in the origin of life.
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(2)
 
(b)	Outline the evidence provided by DNA for the common ancestry of living organisms.
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(2)

(c)	The cladogram below shows the classification of species A to D. Deduce how similar species A is to species B, C and D.
		
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(2)
 
(d)	Suggest two reasons for using cladograms for the classification of organisms.
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(2)
(Total 8 marks)

24.	Discuss, using examples, the importance of cultural and genetic factors in human evolution.
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(Total 6 marks)

25.	(a)	Identify two processes needed for the spontaneous origin of life on Earth.
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(2)
 
(b)	Outline ideas about the pace of evolution according to gradualism and punctuated equilibrium.
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(2)

(c)	(i)	Define a clade.
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(1)

(ii)	Analyse the relationship between the organisms in the following cladogram.

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(3)
(Total 8 marks)

26.	Explain the biochemical evidence provided by DNA and protein structures for the common ancestry of living organisms.
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(Total 6 marks)

27.	Which of the following will promote variation in a species?
I.	Meiosis
II.	Fertilization
III.	Natural selection
A.	I only
B.	II only
C.	I and II only
D.	I, II and III
(Total 1 mark)

28.	Why has antibiotic resistance evolved in bacteria?
A.	All bacteria reproduce very quickly.
B.	Bacteria exposed to antibiotics developed a resistance to them.
C.	Varieties of bacteria resistant to antibiotics reproduce faster than non-resistant varieties.
D.	Bacteria showing resistance to antibiotics survive after antibiotics are used.
(Total 1 mark)

29.	(a)	The graph below shows the half-life of Strontium-90.

	Define the term half-life using the graph above.
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(2)

(b)	Outline the date and distribution of Australopithecus afarensis illustrated by the fossils found.
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(2)
(Total 4 marks)

30.	(a)	Describe transient polymorphism.
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(3)

(b)	Explain how punctuated equilibrium affects the pace of evolution.
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(4)
(Total 7 marks)

31.	Superoxide dismutase is an enzyme used by cells to protect themselves against oxidative damage. These enzymes can have different metals as part of their structure.
	A study to compare two dismutases from Escherichia coli bacteria and two dismutases from eukaryotic cells was undertaken. The following enzymes were used:
•	E. coli dismutase with iron (Fe)
•	E. coli dismutase with manganese (Mn)
•	eukaryotic mitochondrial dismutase with manganese (Mn)
•	eukaryotic cytoplasmic dismutase with copper-zinc (Cu-Zn).
	The following shows part of the amino acid sequences of these enzymes. Boxes enclose identical amino acids in the sequence of the two E. coli and mitochondrial dismutases.

	[Steinman, H M and Hill, R L. 1973. “Sequence homologies among bacterial and mitochondrial superoxide dismutases”. PNAS. Vol 70, issue 12. Pp 3725–3729. Used with the permission of the authors.]
 
(a)	State how many amino acids are in the same position in the E. coli (Fe), E. coli (Mn) and the mitochondrial dismutase sequences shown.
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(1)
 
(b)	State the amino acids which are present in the same position in at least one bacterial dismutase and in both eukaryotic dismutases.
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(1)

(c)	Compare the E. coli (Mn) and the mitochondrial dismutases.
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(2)
 
(d)	Using the diagram, suggest whether the evolution of bacterial dismutase and cytoplasmic dismutase is convergent or divergent.
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(1)

(e)	The sequences of the two bacterial dismutases and the mitochondrial dismutase show a high degree of homology. Discuss how this supports the endosymbiotic theory for the origin of mitochondria.
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(2)
(Total 7 marks)

32.	(a)	Define the terms allele frequency and gene pool.
Allele frequency: ........................................................................................................
Gene pool: ...................................................................................................................
(1)
 
(b)	State one assumption made when the Hardy–Weinberg equation is used.
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(1)

(c)	Outline how variations in specific molecules can lead to phylogeny.
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(3)
 
(d)	Outline the value of classifying organisms.
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(2)
(Total 7 marks)

33.	Discuss the incompleteness of the fossil record and the resulting uncertainties concerning human evolution.
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(Total 6 marks)

34.	Which process tends to reduce variety within a population?
A.	Natural selection
B.	Random fertilization
C.	Independent assortment
D.	Crossing over
(Total 1 mark)

35.	There is evidence that body size of animals tends to increase over time. In this study, fossils and living species from the genus Poseidonamicus, deep-sea ostracods, were used to test this hypothesis. The numbers on the dotted line represent the number of different Poseidonamicus species found either as fossils or living. For each time period, the average valve length of all species studied is plotted. Valve length is an indication of total body size. The continuous line is the estimated temperature of their deep-sea habitat.
		
	[Adapted from Gene Hunt and Kaustuv Roy. 2006. “Climate change, body size evolution, and Cope’s Rule in deep-sea ostracodes”. Proceedings of the National Academy of Sciences. Vol 103, issue 5. Pp 1347–1352 (Figure 1). Copyright 2006, National Academy of Sciences, USA.]
 
(a)	Calculate the percentage increase in valve length between the species studied from 40 million years ago and the species from the present day.
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(2)

(b)	Suggest two reasons for the increase in the number of species of Poseidonamicus over time.
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(2)
 
(c)	Evaluate the hypothesis that changes in size of Poseidonamicus are caused by changes in sea temperature.
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(3)
(Total 7 marks)

36.	(a)	Describe the processes needed for the spontaneous origin of life on Earth.
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(3)
 
(b)	Discuss the endosymbiotic theory for the origin of eukaryotes.
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(3)
(Total 6 marks)

37.	(a)	Describe two major anatomical features of humans that define them as primates.
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(2)
 
(b)	Discuss the implications of the incompleteness of the fossil record on our understanding of human evolution.
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(3)
(Total 5 marks)

38.	(a)	State two properties of RNA that would allow it to play a role in the origin of life.
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(2)
 
(b)	Outline the experiment of Miller and Urey into the origin of organic compounds.
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(3)
(Total 5 marks)

39.	(a)	Define the term gene pool.
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(1)

(b)	Compare allopatric speciation and sympatric speciation.
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(4)
 
(c)	Explain the correlation between the change in diet and increase in brain size during hominid evolution.
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(2)
(Total 7 marks)

40.	What is the mechanism of natural selection?
A.	Any individuals in a population can be selected entirely by chance.
B.	After a change in the environment a species will evolve adaptations to the new conditions.
C.	If an adaptation to the environment is useful, an individual will develop it and pass it on to its offspring.
D.	Variations amongst individuals of a population are selected by a changing environment.
(Total 1 mark)

41.	(a)	State one process needed for the spontaneous origin of life on Earth.
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(1)
 
(b)	Outline the contribution of prokaryotes to the creation of an oxygen-rich atmosphere.
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(2)
(Total 3 marks)

42.	(a)	Outline allopatric and sympatric speciation.
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(4)

(b)	Explain the biochemical evidence for the common ancestry of living organisms.
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(6)
(Total 10 marks)

43.	The rate of nucleotide substitution is used as an indication of evolutionary change. A study was carried out on mitochondrial DNA and nuclear DNA of different species of Acropora, a Pacific Ocean coral.
	The dark grey bars represent the range of genetic sequence divergence between the species for specific mitochondrial DNA sequences (mtDNA) and the light grey bars represent specific nuclear DNA sequences (nDNA).
		
	[Shearer, T L et al. 2002. “Slow mitochondrial DNA sequence evolution in the Anthozoa (Cnidaria)”. Molecular Ecology. Vol 11, issue 12. Pp 2475–2487. © John Wiley & Sons Inc. Reproduced with permission.]
 
(a)	Measure the percentage of maximum genetic divergence for the mtDNA2 sequence.
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(1)
 
(b)	Calculate the maximum difference in genetic divergence between the mtDNA5 sequence and nDNA6 sequence.
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(1)

(c)	Compare the variations in the range of genetic divergence of the mtDNA and nDNA sequences.
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(3)

(d)	Discuss the significance of this data in terms of possible evolutionary changes in these genes.
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(3)
(Total 8 marks)

44.	(a)	State one difference between cultural evolution and genetic evolution.
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(1)

(b)	Outline the pace of evolution as implied in the theory of punctuated equilibrium.
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(2)
(Total 3 marks)

45.	(a)	Using examples, distinguish between analogous characteristics and homologous characteristics.
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(4)

(b)	Albinism, a lack of pigmentation in skin and hair, is caused by a recessive allele.
Albinism occurs in North America in approximately one in 20 000 persons. Explain how the Hardy-Weinberg equation is applied in this example.
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(5)
(Total 9 marks)

46.	Charles Darwin used domesticated animals to provide evidence for evolution by natural selection.
What is this evidence?
A.	Differences between breeds show that selection can cause species to change.
B.	The ancestors of domesticated animals can be found in the fossil record.
C.	Some domesticated animals die because the environment cannot support them all.
D.	Variation in domesticated animals is due to sexual reproduction.
(Total 1 mark)

47.	(a)	State the conclusion drawn from the Miller-Urey experiment.
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(1)
 
(b)	Outline two pieces of evidence that support the endosymbiotic theory for the origin of eukaryotes.
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(2)
(Total 3 marks)

48.	(a)	Compare sympatric speciation and allopatric speciation.
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(2)
 
(b)	(i)	State one species in the genus Australopithecus.
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(1)
 
(ii)	For this species, state the geographical distribution and approximately how many years ago it lived.
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(2)

(c)	Discuss the concept of punctuated equilibrium.
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(3)
(Total 8 marks)

49.	(a)	Compare sympatric speciation and allopatric speciation.
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(2)
 
(b)	Define analogous characteristics using one example to illustrate your answer.
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(1)

(c)	Outline two pieces of evidence that support the endosymbiotic theory for the origin of eukaryotes.
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(2)
 
(d)	List two anatomical features that define humans as primates.
1. ..................................................................................................................................
2. ..................................................................................................................................
(2)
(Total 7 marks)

50.	Explain the biochemical evidence for the common ancestry of living organisms.
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(Total 6 marks)

51.	Which process has the greatest effect in determining which members of a population are most likely to survive until reproductive age?
A.	Evolution
B.	Natural selection
C.	Meiosis
D.	Hybridization
(Total 1 mark)

52.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Draw and label a diagram of the molecular structure of DNA.
(4)
(b)	Explain the consequences of a base substitution mutation in relation to the processes of transcription and translation.
(8)
(c)	Outline the evidence for evolution provided by homologous structures.
(6)
(Total 20 marks)

53.	The tree diagram (cladogram) below shows how closely related a group of species of spiders are on the Hawaiian island group. Two of the species have not been given a scientific name. Three pairs of the spiders spin very similar webs. These are shown on the diagram. The island on which the spider lives is also indicated.

[Source: T A Blackledge and R G Gillespie (November 2004), Proceedings of the National Academy of Sciences, 101, (46),
pages 16228-16233]
 
(a)	State which species is most distantly related to T. perkinsi on the basis of the tree diagram.
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(1)
 
(b)	Explain the evidence in the diagram for
(3)

(i)	convergent evolution
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(ii)	adaptive radiation
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(c)	Deduce whether spiders that spin similar webs or spiders that live on the same island are more closely related.
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(2)
(Total 6 marks)

54.	(a)	Define sympatric speciation.
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(1)

(b)	Describe two examples of barriers between gene pools.
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(4)
(Total 5 marks)

55.	(a)	Define half-life.
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(1)

(b)	Discuss gradualism and punctuated equilibrium.
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(6)
(Total 7 marks)

56.	Up to two additional marks are available for the construction of your answers.
(2)
	(a)	Draw a labelled graph showing a typical sigmoid growth curve.
(4)
(b)	Outline the consequences of an increased greenhouse effect on arctic ecosystems.
(6)
(c)	Explain how natural selection leads to evolution.
(8)
(Total 20 marks)

57.	The cladogram below shows how closely related a group of species of spiders are on the Hawaiian island group. Two of the species have not been given a scientific name. Three pairs of the spiders spin very similar webs. These are shown on the diagram. The island on which the spider lives is also indicated.

[Source: T A Blackledge and R G Gillespie (November 2004), Proceedings of the National Academy of Sciences, 101, (46),
pages 16228-16233]
 
(a)	Deduce whether spiders that spin similar webs or spiders that live on the same island are more closely related.
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(2)
 
(b)	Mitochondrial DNA from the spiders was analysed to produce the cladogram. Outline the method of analysing the DNA to produce evidence for cladograms.
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(3)
 
(c)	Explain the evidence in the diagram for
(3)
 
(i)	convergent evolution;
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(ii)	adaptive radiation.
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(Total 8 marks)

58.	(a)	Outline properties of RNA that may have played a role in the development of life on this planet.
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(2)
 
(b)	State two types of molecules used in the experiments of Miller and Urey to simulate the atmosphere of pre-biotic earth.
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(1)
 
(c)	Outline the endosymbiotic theory.
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(4)
(Total 7 marks)

59.	Discuss the correlation between change in the diet and increase in brain size in early hominid evolution.
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(Total 5 marks)