Animal Behavior Comprehensive Review PDF

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Weeks 8-13 lectures and past exam review....

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Previous Exam Papers Review: Habituation: Overtime, lizards reduce their response to the stimuli and learn that humans do not pose a threat. Associative (Operant) Conditioning: Associated with trial-and-error learning, the animal associate an outcome (pecking at the visual stimulus) with a positive reward (food). Classical conditioning/learning: a learning process that occurs when two stimuli are repeatedly paired: a response which is at first elicited by the second stimulus is eventually elicited by the first stimulus alone. Spatial learning: The animals used cues such as orientation and distance between flowers to learn the location of food source. Latent learning: animals observing their surroundings with no particular motivation to learn the geography of it; however, at a later date, they are able to exploit this knowledge when there is motivation - such as the biological need to find food or escape trouble. Imprinting: A process whereby a young animal follow the characteristics of his/her mother after hatching. Dispersal: the movement of animals away from their natal area Animal culture can be defined as specific information or behaviour that is acquired from conspecifics through some form of social learning, which can have important consequences for the survival and reproduction of individuals, social groups, and entire populations. Discuss, using examples, why we need to understand animal cultures for conservation efforts. (4 marks) – important when traits are learnt e.g. foraging tactics and vocal behavior. – Populations may be structured into distinct cultural units with differing resource requirements (e.g. cultural transmission of vocal patterns in sperm whales) – May be important for migration routes in whooping cranes (Lecture 5) or other species if specific information is learnt from cultural groups – African elephant matriarchs show to positively impact the fertility rates of younger females through cultural transmission of information about the social and ecological landscape. Nikolaas Tinbergen (1907–1988) was a Nobel prize-winning ethologist who made a number of contributions to animal behaviour, but is most remembered for his articulation of four fundamental questions that he argued should be incorporated into the study of any animal behaviour. These should be asked when discussing how and why an animal exhibits a certain behaviour. • Describe these four questions in relation to proximate and ultimate mechanisms. Use cryptic wing colouration in peppered moths as an example (4 marks). Proximate questions 1. Mechanisms: What are the physiological mechanisms involved in a behaviour? How are colour patterns produced in moths?

2. Development: How does a behaviour develop in an individual? -Are colour patterns genetic traits? Do the colour patterns change over the lifetime of the moth? Ultimate questions 3. Function: What is the survival value of the behaviour? - Are cryptic moths protected more based on their colour pattern? 4. Evolution: How did the behaviour evolve in the phylogenetic history of the species? - How does colour patterns relate to closely related species? Are sister species also cryptic? Match the correct learning category to each example below and explain your reasoning using the definition of the type of learning. Choose only from the following six categories of learning: habituation, associative (operant) conditioning; classical conditioning/learning; spatial learning; latent learning; imprinting. i)

ii)

iii)

Colour patterns displayed by animals frequently comprise multiple elements, including colour, pattern, luminance and texture. Coral reef fish were trained to receive a food reward by pecking at visual stimulus with different colour patterns in the presence of an unrewarded distractor. [2 marks] Operant conditioning The behavioural response to repeated simulated predatory attacks was investigated between adult males of the common wall lizard, Podarcis muralis, inhabiting environments characterised by different degrees of human presence. Urban lizards spent less time in their refuge after predatory attacks and decreased successive hiding times faster than rural lizards. [2 marks] Habituation A study examined how rufous hummingbirds, Selasphorus rufus, learned the location of a reward. Their ability to learn the location in a linear flower array depended on its orientation and on the distance between the flowers in the array. [2 marks] Spatial learning

Under what three conditions will behaviours evolve by natural selection? (3 marks) From Lecture 3: 1. Variation exists among individuals within and between populations in the traits they possess 2. Individuals’ different traits are, at least in part, heritable. Traits can be passed from parents to their offspring so that offspring resemble their parents in the traits they possess 3. Traits confer differences in survivorship and reproduction, a measure we call fitness: individuals with certain traits will have higher fitness, while those with other traits will have lower fitness relative to one another. Therefore, the fitness of individuals is not random; it is based on the traits they possess. From 1987 to 1994, the annual frequency of adoption by breeding pairs of ring-billed gulls, Larus delawarensis, at a Lake Erie colony ranged from 3 to 37% (average 8% per year, N=7 years) and, on average, foster parents raised 0.5 fewer of their own chicks to fledging than pairs that did not adopt. In terms of proximate and ultimate explanations, provide 3 hypotheses why ring-billed gills may foster chicks. (3 marks) Many options for this question, some examples are:

• • • •

Foster parents are inexperienced breeders therefore gain parental experience before raising their own offspring (development – proximate, and function) Foster occurs prior to parent-offspring recognition capabilities (reproductive error; mechanism – proximate). Fosters parents raise chicks that are closely related to them (kin selection) (function - ultimate) Evidence of reciprocation: donor parents one year may be foster parents the next year. (function – ultimate)

Male house sparrows signal their dominance (social ranking) by using a visual signal: the size of their badge. The badge size has been shown to be related to testosterone levels. Sparrows that are ranked higher (towards 1) are more likely to challenge sparrows that are ranked lower (towards 10). The badge size is regarded as an honest signal as it is too costly to be deceitful. Define the handicap principle in honest signalling. (2 marks) The handicap principle states that honest signals must cost the signaller something that could not be afforded by an individual with less of a particular trait. Signal receivers know that the signals indicates quality because inferior quality signallers and unable to produce such wasteful signals. State a potential cost to the sparrow if it displayed a deceitful badge signal. (2 marks) - May incur injury in hierarchical dispute as would have less testerone that indicated by the badge and may therefore be less aggressive. - May encounter increase aggression from conspecifics. Signalling behaviour will occur between higher and lower ranking sparrows when competing for feeding patches. Describe the three potential competitive interactions that may occur and include the likely outcome of each interaction. (6 marks) High vs low: high ranking sparrow signals to low ranking sparrow who is submissive. H maintains high dominance with priority to feed at patches. High vs high ranking: high rankings sparrows may continue to signal and may be aggressive to one another. One will eventually submit and the other win. Sparrows may be damaged in dispute. Low vs low ranking: may equally distribute resources so interaction does not become aggressive. Dispersal is the movement of animals away from their natal area. What distinguishes dispersal from migration? Briefly explain two of the main drivers of dispersal. (3 marks) • • •

Dispersal: movement that takes an animal from its birthplace to a different population or that leads to a colonisation of a new habitat. Migration: often seasonal movement where individuals return to the same area repeatedly Main drives of dispersal: 1) inbreeding avoidance, 2) competition [provide brief explanation of each]

Migration can also alter the potential impacts of pathogens on individuals and populations. Briefly describe one way that migration can increase the impact of pathogens on individuals

AND populations, and one way in which migration can reduce the impacts of pathogens on individuals AND populations. (4 marks) • Increase: a) migrating animals can use stopover sites on their journey where they can spread pathogens to other animals. B) migration is energetically expensive and animals may therefore become be more susceptible to pathogens. • Reduce: through migratory escape. Fitter, unparasitized individuals leave infected area and allow the region to recover. Population suffers fewer mortalities as lower rates of disease. Design an experiment to test if a particular species of shore bird uses a sun compass to navigate. What results would you expect? (3 marks) • Time-shift experiment • Phase-delay or phase-advance individuals so that their circadian rhythms are entrained to be out of phase with the normal day-night cycle. • Release the birds at particular time of day and record whether they still go in the same direction based on sun location or based on circadian rhythm Two approaches to estimating the heritability of behaviour are: (1) twin studies in humans and (2) cross-fostering experiments in animals such as birds. (DAVID MERRITT) Explain what twin studies entail, including information on the types of twins that can be studied, why they contribute differently to estimating heritability, and the expected outcomes when twins grow up in different environments. Give an indication of the insights derived from these studies on the heritability of human traits. (5 marks) (DAVID MERRITT) Explain what cross-fostering experiments with animals entail. Give an example of a crossfostering experiment and describe what the experiments tells us about the heritability of behaviour. (5 marks) (DAVID MERRITT) Which of the following forms of sexual selection is most likely to be responsible for the bizarre morphology of males in these flies, 1) precopulatory female choice, 2) postcopulatory female choice, 3) precopulatory male competition, 4) postcopulatory male competition? Explain why you have chosen one of these and rejected the others (3 marks) (DAVID MERRITT) Precopulatory female choice – females choose males with larger eye spans as they are indicative of improved male condition. Not likely to be postcopulatory male competition as larger eye stalks are unlikely to provide an advantage when mating with females Not likely to be precopulatory male competition as unlikely to confer an advantage in male-male competitive interactions. Foraging plays an important role in an animal's ability to survive and reproduce. a) What are three assumptions of the diet model of optimal foraging (3 marks) (Diana) Individuals maximise fitness by maximising energy intake Food items are encountered 1 at a time in proportion to abundance and evening distributed throughout patches Food items are always eaten or always rejects (0 or 1).

b) What is a GUD apparatus? What is the name of the model on which this approach is based? Give an example of a hypothesis that you could test using this technique, and explain how you would test the hypothesis using a GUD approach. (5 marks) (Diana) Giving-Up Density apparatus. [Explain what it is] Optimal Patch Use model Describe a suitable experiment c) In the context of predator-prey behaviour, what is a ‘landscape of fear’. Explain this term and the outcome of a ‘landscape of fear’ using an example. (2 marks) (Diana) The landscape of fear represents relative levels of predation risk as peaks and valleys that reflect the level of fear of predation a prey experiences in different parts of its area of use. The figure below shows the time of day when individual human infants slept from their first week to their 25th week. Sleep:wake pattern in 3 human infants. The dark bars indicate times when the subject is asleep. Explain the rationale behind displaying the data this way (2 marks) (David) Presenting data like this allows us to observe patterns and changes in rhythms over time. It is also easy to see variation between individuals. B) What do the three plots tell us about the development of circadian rhythmicity of the sleep:wake pattern in human infants. (3 marks) (David) Circadian rhythms take a while to develop. Very young infants show little rhythm, but as they age then rhythm emerges (at about 6-10 weeks) and sleep-wake cycles become more regular. However, there is considerable variation between individuals (e.g. individual HS still very irregular) C) Why would the sleep-wake pattern of individual infants change over time? (2 marks) (David) Sleep-wake cycles take time to entrain. Infants have no exposure to dark- light cycles in womb and need exposure to light to entrain the rhythm. D) Give some well-argued reasons why the individual labelled “HS” shows diagonal patterns in the sleep:wake cycle, how they would arise and what this could mean. (3 marks) (David) HS is displaying a free-running cycle. When entrainment does not occur, rhythms will instead free-run at their own endogenous period. May be due to blindness, genetic mutation, no exposure to day-night rhythms. Species respond to humans and urban environments in a wide range of ways. (Salit) a) Discuss the differences between urban exploiters, urban adapters, and urban avoiders. Give examples of each. (5 marks). b) Discuss five traits that allow species to succeed in novel and human-dominated landscapes (e.g., urban environments)? (5 marks) WEEK 8 LECTURE 1: ANIMAL MOVEMENT

Animals move to find optimal conditions: -Food, mates, avoiding predators and other hazards • Ability to move one of the most fundamental characteristics animals • Requires integration of sensory inputs & innate abilities/ knowledge • Varies enormously in scale • Large range of motivations • Much of it remains a mystery! Large-scale movements: * dispersal * homing * migration Concepts: 1. Dispersal reduces resource competition and inbreeding - Avoidance of aggressive conspecifics may make natal habitat suboptimal - Risky stage of life as all suitable habitat may be occupied • Simplest form is finding suitable habitat after hatching • In most mammals & birds, dispersal ‘encouraged’ in adolescents • In mammals, males disperse more often & further than females • Usually polygynous • Males often form roving bachelor groups; shared benefits & sparing partners • In some primates pregnant females or females w neonates may temporarily disperse to protect young particularly from males • In birds, females more likely to disperse • Birds more usually monogamous, females dispersing further to find males with good territories Competition dispersal • Simple competition for resources Inbreeding avoidance • Does not matter which sex disperses Colonisation dispersal • Disperse specifically to colonise new habitats • Inseminated females often at the vanguard, or disperse in pairs • Insects, rats, rabbits 2. Reproductive success and public information affect breeding dispersal Breeding dispersal: abandoning one breeding site and moving to another Many species exhibit site fidelity after a reproductive success and exhibit breeding dispersal after a reproductive failure (win-stay lose-shift pattern) Public information from conspecifics affects breeding dispersal • Public information: Information obtained from the activity or performance of others about the quality of an environmental parameter or resource 3. Individuals migrate in response to changes in the environment

Migration chracteristics: • Typically an annual movement between seasonal habitats • Differs from dispersal in that it involves a return • Usually annual, usually multiple times within a lifetime • But sometimes multiple generations per migration • Species exposed to variable environmental conditions & resources more likely to migrate than species in more stable resource environments • Widespread e.g. butterflies, turtles, birds, mammals • Some animals route is innate – butterflies, turtles • Others it is learned – probably most birds, mammals - In many animals there are clear & obvious destinations (e.g. whales) - In others, resources en route may be as important as the destination (e.g. African ungulates) • Patterned nomadism? • Often migratory stopovers important – a series of goals Migration and Conservation: • Migratory animals represent particular challenges with conservation • Often move across many jurisdictions/ countries with different conservation values • Routes blocked or disrupted • Fragmentation of landscapes • Roads, fences, buildings • Damming of rivers African Ungulates: • Movements often triggered not by time of year, but by onset of rains, drought • Following of learnt “traditional routes” • Movements under great pressure • Fences, roads, new towns, habitat fragmentation • Climate change Polymorphism: the occurrence of two or more clearly different morphs or forms, also referred to as alternative phenotypes, in the population of a species. • Migratory behavior could be a fixed, genetic trait, and frequency-dependent selection maintains the polymorphism • Migratory behavior is dependent on individual condition 4. Environmental cues and compass systems are used for orientation when migrating Orientation • Determination and maintenance of a proper direction Navigation • Determining a particular location and moving toward it Sun compass • Use of sun for orientation

Star compass • Use of stars or constellations to orient Geomagnetic compass • Ability to orient using the earth’s magnetic field 5. Bicoordinate navigation allows individuals to identify their location relative to a goal

WEEK 8 LECTURE 2: ANIMAL MOVEMENT Star Compass system: Dung beetles: Experiment done in planetarium shows erratic movement in the absence of starry sky (specifically milky way) Geomagnetic compass: No evidence that we use/have a magnetic sense “Hidden sense” probably allocated to cellular level -11 things we know are there but can’t find (dark matter, magnetoreception) Magnetoreception: Good evidence across a broad range of taxa -bacteria, drosphilia, migratory birds, newts, honeybees Compass is different from a coordinate system: Bi-cordinate navigation: Allows individuals to identify their location relative to a goal Ways migration can alter the impacts of pathogens on a population: 1.) Immunomodulation during preparation for migration 2.) Migratory culling 3.) Mixing with other species/populations on stopover sites 4.) Migratory Escape Immunomodulation: as animals prepare for migration they put energy towards trying to get fat; immune system function is relatively downregulated and pathogens may be more likely to spread/take hold Migratory culling: Range of infected and uninfected individuals travelling across migratory path. Selects against virulent pathogens; pathogens that kill the host are poorly designed pathogens. Deadly pathogens are likely not to have been evolved with humans Poor evolutionary success rate if kills host Common cold: makes you “just sick enough” Mixing with other species/populations on stopover sites: Population A affects population B, C, and D Migratory Escape: Particularly effective for multicellular parasites Ex: Feces containing worm eggs

If pathogen has a life stage that is outside the host, and can build up in areas overtime but still dependent on host for some point of lifecycle; population leaves and area is “cleansed upon return. Homing: movement of animals towards a home base -Highly variable time scale based on species -Salmon imprint on odor and chemical properties of home river; also use magnetoreception - Classic bicordinate navigation using two different senses Homing pigeons: -Variety of domestic pigeons selectively bred to “home” to a roost -Used extensively as messenger pigeons (3,000 years)...