1.	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.
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(1)

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

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(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)

2.	The graph below shows the monthly mean values of terrestrial invertebrates from May 1997 to June 1998 in the northern hemisphere. The light line shows the biomass of invertebrates which are prey to forest birds (terrestrial invertebrate biomass). The darker line shows the invertebrates which lived in the stream and have moved to the forest (aquatic invertebrate flux or movement). The black bars on the horizontal line at the bottom show periods when trees have leaves and the white bars show periods of defoliation.
		
	[S Nakano and M Murakami. 2001. “Reciprocal subsidies: Dynamic interdependence between terrestrial and aquatic food webs.” PNAS. Vol 98, issue 1. Pp 166–170. Figure 1C. Copyright (2001) National Academy of Sciences, USA.]
 
(a)	State the mean terrestrial invertebrate biomass measured in August.
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(1)
 
(b)	Describe the trend in the aquatic invertebrate flux.
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(2)
 
(c)	Suggest the relationship between defoliation and the amount of terrestrial invertebrates in the forest.
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(2)
 
(d)	Suggest a possible explanation for the pattern in aquatic invertebrate flux to the forest seen between the months of June and December.
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(2)
(Total 7 marks)

3.	The effect of social stimulation on the reproductive patterns of egg-laying female Zebra finches (Taeniopygia guttata) was studied. The sounds of the same colony (intra-colony) and of a different colony (extra-colony) were recorded and played to different pairs of Zebra finches.
	Graph A shows the mean time until the laying of the first eggs. Graph B shows the mean clutch size (total number of eggs per pair). The control pairs had no recordings played to them.

	[Source: J Waas et al. 2005. Proceedings of the Royal Society. Vol 272. Pp 383–388. Reproduced with permission.]

(a)	Identify the mean time until the laying of the first eggs in the control group of Zebra finches.
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(1)
 
(b)	Calculate the percentage decrease between the mean time until the laying of the first eggs in pairs of Zebra finches exposed to intra-colony sounds and in pairs exposed to extra-colony sounds. Show your working.

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(2)
 
(c)	Evaluate the effect of the recorded colony sounds on the reproductive pattern of laying eggs in Zebra finches.
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(3)
(Total 6 marks)

4.	Desert ants (Cataglyphis fortis) use odour to help find their food. When a constant wind is blowing, the ants do not approach food directly. Instead, they walk downwind of the food source and then, when they detect the odour of the food, they follow the odour trail upwind until they reach the food, as shown in the figure below.
		
	[The Journal of Experimental Biology: jeb.biologists.org.]
 
	To investigate this behaviour pattern, feeders were established at distances of 5 m to 60 m away from the nest. Each feeder consisted of a Petri dish filled with biscuit crumbs. The graph below shows the distribution of downwind approach distances for each different nest-feeder distance.
		
	[Source: Harald Wolf and Rudiger Wehner, “Desert Ants Compensate for Navigation Uncertainty”, Journal of Experimental Biology, 208 (22), Nov. 2005, pages 4223-4230: Figures 1 and 4. Adapted with permission.]

(a)	Outline the relationship between the downwind approach distance and the nest-feeder distance.
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(1)
 
(b)	Compare the results observed when the feeders were located at 5 m with the feeders at 60 m.
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(3)
 
(c)	Suggest one possible source of uncertainties or errors in these experiments.
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(1)
 
(d)	Deduce, with a reason, what type of behaviour pattern is shown by the ants in the experiment.
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(2)
(Total 7 marks)

5.	Desert ants (Cataglyphis fortis) use odour to help find their food. When a constant wind is blowing, the ants do not approach food directly. Instead, they walk downwind of the food source and then, when they detect the odour of the food, they follow the odour trail upwind until they reach the food, as shown in the figure below.

	[Adapted with permission from Wolf, H and Wehner, R. 2005. Journal of Experimental Biology. Vol 208. Pp 4223–4230. Where appearing online or in other electronic media, a link should be provided to the original article (eg, via DOI): The Journal of Experimental Biology: jeb.biologists.org.]
 
	To investigate this behaviour pattern, feeders were established at distances of 5 m to 60 m away from the nest. Each feeder consisted of a Petri dish filled with biscuit crumbs. The graph below shows the distribution of downwind approach distances for each different nest-feeder distance.
		
	[Adapted with permission from Wolf, H and Wehner, R. 2005. Journal of Experimental Biology. Vol 208. Pp 4223–4230. Where appearing online or in other electronic media, a link should be provided to the original article (eg, via DOI): The Journal of Experimental Biology: jeb.biologists.org.]

(a)	Outline the relationship between the downwind approach distance and the nest-feeder distance.
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(1)
 
(b)	Compare the results observed when the feeders were located at 5 m with the feeders at 60 m.
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(3)
 
(c)	Suggest one possible source of uncertainties or errors in these experiments.
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(1)
 
(d)	Deduce, with a reason, what type of behaviour pattern is shown by the ants in the experiment.
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(2)
(Total 7 marks)

6.	Evidence suggests that the behaviour of bees is often a response to odours. Scientists placed bees 200 cm away from an attractive odour source. An experimental group of bees had previous exposure to the odour, a control group had no previous exposure. Both the percentage of bees flying towards (orientated flight) and the percentage circling the odour source were measured.
		
	[Source: Antoine Chaffiol, David Laloi, and Minh-Hà Pham-Delègue. 2005.  “Prior classical olfactory conditioning improves odour-cued flight orientation of honey bees in a wind tunnel”. Journal of Experimental Biology. Vol 208, issue 19. Pp 3731–3737 (Figure 3). © Company of Biologists Ltd.]
 
(a)	Calculate the percentage increase in orientated flight between the control group and the experimental group.
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(1)
 
(b)	Describe the effect of previous exposure to the odour on the flight of bees.
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(2)

(c)	Outline the type of behaviour that the experimental group demonstrates.
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(d)	Discuss the implications of this study for the survival of bees.
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(3)
(Total 7 marks)

7.	Evidence suggests that the behaviour of bees is often a response to odours. Scientists placed bees 200 cm away from an attractive odour source. An experimental group of bees had previous exposure to the odour, a control group had no previous exposure. Both the percentage of bees flying towards (orientated flight) and the percentage circling the odour source were measured.
		
	[Source: Antoine Chaffiol, David Laloi, and Minh-Hà Pham-Delègue. 2005. “Prior classical olfactory conditioning improves odour-cued flight orientation of honey bees in a wind tunnel”. Journal of Experimental Biology. Vol 208, issue 19. Pp 3731–3737 (Figure 3). © Company of Biologists Ltd.]
 
(a)	Describe the effect of previous exposure to the odour on the flight of bees.
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(2)
 
(b)	Outline the type of behaviour that the experimental group demonstrates.
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(1)

(c)	Discuss the implications of this study for the survival of bees.
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(3)
(Total 6 marks)

8.	Cooperative breeding in birds occurs when more than two birds of the same species help to rear the young from one nest. For the Australian superb fairy-wren (Malurus cyaneus), mature non-breeding birds help to protect and rear the young, although they are not parents of any of them.
	The bar charts below show the effect of the presence of helpers on mean egg volume, mean mass of six-day-old chicks and the probability of survival of the breeding females until the next breeding season.

	[From Russell, A F et al. 2007. Science. Vol 317. Pp 941–944. Reprinted with permission from AAAS.  Readers may view, browse, and/or download the material for temporary copying purposes only, provided these uses are for noncommercial personal purposes. Except as provided by law, this material may not be further reproduced, distributed, transmitted, modified, adapted, performed, displayed, published, or sold in whole or in part, without prior written permission from the publisher.]

(a)	State the effect of the presence of the helpers on
(i)	mean chick mass.
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(ii)	the probability of survival of the breeding females until the next breeding season.
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(b)	Calculate the percentage decrease in mean egg volume found in the presence of helpers as compared to the parents only. Show your working.
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(2)

(c)	With reference to the data, suggest why the activity of the helper affects the probability of survival of the breeding female until the next breeding season.
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(Total 6 marks)

9.	(a)	Compare rods and cones.
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(3)
 
(b)	Explain the role of receptors, sensory neurons and motor neurons in the response of animals to stimuli.
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(3)

(c)	List four general kinds of sensory receptor.
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(2)
(Total 8 marks)

10.	(a)	Distinguish between a conditioned response and an unconditioned response.
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(2)
 
(b)	Explain the effect of tetrahydrocannabinol (THC) on brain function.
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(2)
(Total 4 marks)

11.	(a)	Explain the role of the neurons used in the pain withdrawal reflex.
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(b)	Distinguish between taxis and kinesis.
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(c)	State one effect of tetrahydrocannabinol (THC) on brain function.
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(1)
(Total 6 marks)

12.	Circadian rhythms are daily cycles in physiology and behaviours. Cryptochromes are proteins that are thought to be involved in circadian rhythm in mammals.
Two groups of mice were identified. Group A could produce cryptochrome, Group B could not. The behaviour of the mice was assessed by monitoring wheel running activity over a 28-day period. For the first seven days the animals were given alternating 12-hour periods of light and dark. Between days 8 and 28 they were kept in continuous darkness.
The rotation of the running wheel is plotted as a dark area within the boxes, the time of day is plotted on the x-axis. The band on top indicates the dark and light periods in the first seven days.

[Source: Aziz Sancar, (August 2004), The Journal of Biological Chemistry, 279, (33), pages 34079-34082]
 
(a)	(i)	State the light conditions when mice were most active during the first 7 days.
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(1)
 
(ii)	Suggest one reason for mice showing this behaviour.
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(1)

(b)	Compare the effect of constant darkness on groups A and B.
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(c)	Evaluate the hypothesis that cryptochromes are necessary for establishing circadian rhythms.
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(2)
(Total 7 marks)

13.	Circadian rhythms are daily cycles in physiology and behaviours. Cryptochromes are proteins that are thought to be involved in circadian rhythm in mammals.
Two groups of mice were identified. Group A could produce cryptochrome, Group B could not. The behaviour of the mice was assessed by monitoring wheel running activity over a 28 day period. For the first seven days the animals were given alternating 12 hour periods of light and dark. Between day 8 and day 28 they were kept in continuous darkness.
The rotation of the running wheel is plotted as a dark area within the boxes, the time of day is plotted on the x-axis. The band on top indicates the dark and light periods in the first 7 days.

[Source: Aziz Sancar (August 2004), The journal of Biological Chemistry, 279, (33), pages 34079–34082]
 
(a)	(i)	State the light conditions when mice were most active during the first 7 days.
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(1)
 
(ii)	Suggest one reason for mice showing this behaviour.
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(1)

(b)	Compare the effect of constant darkness on groups A and B.
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(3)
 
(c)	Evalute the hypothesis that cryptochromes are necessary for establishing circadian rhythms.
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(2)
(Total 7 marks)

14.	(a)	Label the diagram of the human ear shown below.
	
[Source: www.msjensen.gen.umn.edu/webanatomy_archive/wa_nervous/wa_ear_1.html]
A : ....................................................................
B : ....................................................................
C : ....................................................................
D : ....................................................................
(2)
 
(b)	Define the term stimulus.
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(1)

(c)	Outline the sympathetic and parasympathetic control of the heart rate.
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(4)
(Total 7 marks)

15.	Discuss the evolution of altruistic behaviour in a non-human species.
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(Total 6 marks)