Name _____________________________________________________ Date ___________________
Populations & Cladistics
1.	Which of the following is the best definition of a population?
A.	A group of individuals that can interbreed and produce fertile offspring
B.	The number of individuals of the same species in a given area
C.	A group of species living and interacting with each other in a given area
D.	The total number of individuals in a given area
(Total 1 mark)
2.	The graph below represents a sigmoid (S-shaped) population growth curve. Three sections of the curve are indicated (1, 2 and 3).
	In which of the sections is natality plus immigration greater than mortality plus emigration?
		
A.	1 only
B.	2 only
C.	1 and 2 only
D.	3 only
(Total 1 mark)

3.	Which graph shows the sigmoid population growth curve?

(Total 1 mark)

4.	If natality is slightly larger than mortality, and immigration is much larger than emigration, what will happen to the size of a population?
A.	It will increase
B.	It will decrease
C.	It will fluctuate up and down
D.	It will remain constant
(Total 1 mark)

5.	In the forest zone between Gabon and the Republic of Congo it is estimated that an epidemic of the Zaire strain of the Ebola virus (ZEBOV) killed nearly 5000 gorillas, significantly reducing the population. Which statement is supported by this information?
A.	Natality was greater than mortality.
B.	Mortality was equal to natality.
C.	Natality and immigration was greater than mortality and emigration.
D.	Mortality was greater than immigration and natality.
(Total 1 mark)

6.	The diagram below shows a population growth curve.
		
	At which time in the population growth curve does the population size begin to decline?
A.	Between the time marked 1 and 2
B.	During the time marked 2
C.	Between the time marked 2 and 3
D.	The graph does not show a time when population size declines
(Total 1 mark)
7.	Population growth, as shown by the curve below, is the result of changes in mortality, natality, immigration and emigration. Which of the following statements about population growth is correct?
		
A.	In phase I there is no mortality.
B.	In phase II mortality equals natality and immigration equals emigration.
C.	In phase II mortality and emigration are less than natality and immigration.
D.	In phase III mortality and emigration are less than natality and immigration.
(Total 1 mark) 
8.	What can limit increases in population size?
I.	Decrease in prey
II.	Decrease in parasites
III.	Increase in predators
A.	I and II only
B.	I and III only
C.	II and III only
D.	I, II and III
(Total 1 mark)
9.	The grey partridge (Perdix perdix) is a species of bird that is found on farmland. Sparrowhawks (Accipiter nisus) and buzzards (Buteo buteo) are birds of prey that kill and feed on birds, including grey partridge. The number of grey partridges in a region of southern England was monitored from 1970 to 2004. The numbers of sparrowhawks and buzzards, seen from sampling positions during regular observation periods, were counted. The results are shown in the graph below.

	[Source: Watson, M et al. 2007. Journal of Applied Ecology. Vol 44. Pp 972–982. Reproduced with the permission of Wiley Blackwell.]

(a)	Outline the trends, over the period of time shown in the graph, in the number of grey partridges, buzzards and sparrowhawks.
Grey partridges: ...........................................................................................................
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Buzzards: .....................................................................................................................
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Sparrowhawks: ............................................................................................................
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(3)
	The density of grey partridge (number per square kilometre) varied considerably in different areas within the study region. The graph below shows the correlation between the density of grey partridges and the density of birds of prey.
		
	[Source: The Journal of Applied Ecology by BRITISH ECOLOGICAL SOCIETY. Reproduced with permission of BLACKWELL PUBLISHING LTD. in the format Journal via Copyright Clearance Center]
(b)	(i)	Identify the correlation between the density of grey partridges and birds of prey.
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(1)
(ii)	Suggest a hypothesis to account for this correlation.
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(2)
	The highest density of birds of prey was found in areas used for recreational shooting. In these areas, other species of partridge were bred and released. Food and shelter were provided for the released birds. These measures tended to increase the number of both released and wild birds.
	The causes of death of grey partridge were investigated in one of the areas that was used for recreational shooting. The pie chart below shows the causes of death.
		
(c)	(i)	Calculate the percentage of deaths due to birds of prey.
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(1)
(ii)	Using the data provided, discuss the causes of the correlation between the density of grey partridges and the density of birds of prey.
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(3)
(d)	Suggest a conservation measure that would be most likely to prevent the extinction of grey partridges from southern England.
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(1)
(Total 11 marks)

10.	What do the graphs below show?

A.	Population in the United States is increasing at a higher rate.
B.	Infant death rate is high in both countries.
C.	Males live longer than females in both countries.
D.	Birth rate is higher in Mexico than in the United States.
(Total 1 mark)

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)