Animal Behaviour Flashcards

Question

Darwin's Problem with Altruism?

Answer 1

The problem revolved around 2 related questions: 1) How can altruism evolve? 2) What is the ‘unit’ of selection? Our own observations of the natural world tells us that animals are primarily concerned and motivated by a few goals. All ultimately concerned with reproduction. Given that ‘nature is red in tooth and claw’ why are there so many examples of altruistic acts?

Answer 2

Florida scrub jay. The basic social unit is a monogamous breeding pair together with offspring from the past 2-3 years. The mature offspring assist younger siblings (e.g., guarding the nest, providing food). Moehlman (1986) reported that one third of the young remain with their parents throughout the following breeding season and assist in rearing. Alarm calls in birds.

Answer 3

Is an important question given that animal behaviour scientists (from an ethological tradition) are primarily concerned with function. i.e., why has helping behaviour been selected? If it doesn’t help then that behaviour can’t have been selected (essentially that behaviour doesn’t exist). One way to find out whether bird helpers really do help is to experimentally remove them from the nest. Emlen (in 1991) reported results from 3 such studies assessing reproductive success. The table clearly shows that helpers do indeed help.

Answer 4

The common explanation was that animals act for the ‘good of the species’ or ‘for the good of the group’. Believed by many senior scientists, e.g., Lorenz. Even Darwin; “There can be no doubt that a tribe including many members who, from possessing in a high degree the spirit of patriotism, fidelity, obedience, courage, and sympathy, were always ready to give aid to each other and to sacrifice themselves for the common good, would be victorious over most other tribes; and this would be natural selection”. The idea existed, almost implicitly, for decades but was formalised by V. C. Wynne-Edwards in 1962 (“Animal dispersion in relation to social behaviour”). Suggested that birds assess their population and if food is short they (self) restrict the number of offspring each will produce.

Answer 5

Natural selection means that, by definition, nature is selecting something. What exactly is it selecting? What is in competition with each other? Individuals -> Kin -> Groups -> Species (Genus, Family, Order). The common answer was the species; species were said to be in competition with each other. The notion that the species is the unit of selection and hence that animals therefore act for the good of the species (e.g., altruism) was/is known as ‘group selectionism’.

Answer 6

1) Species don’t exist, they are constructed. (Many phenomena are constructed: weeds, terrorism. This is itself examined by psychologists, ‘social constructionism’). Ability to mate is not a good definition of species, e.g., sheep and goats. 2) Those individuals who act selfishly (‘defect’) will always have an advantage. E.g. A murmuration of Starlings. An individual will not look around for any predators. Allowing it to eat more and to then have more time to reproduce. That is why selfish gene individuals always have an advantage. They they reproduce and make more selfish animals. Meaning overtime all individuals of that population of species will become "selfish". Applies even when everyone is acting for the good of the group. A defector mutation will always gain an advantage.

Answer 7

What if a defector occurs who doesn’t bother doing any looking, just gets on with feeding. That starling will have quite a large advantage over its colleagues. Why? For instance, because it doesn’t spend anytime looking, just eating, it is satiated quicker. It can then spend more time on other things. It is therefore more likely to have offspring, and if that trait for not looking up is inherited its offspring will also not look for predators when feeding. Soon the whole population will comprise individuals who do not bother to look for predators when feeding. However, this clearly does not happen – the starlings act altruistically. This defector-advantage principle can be seen in Wynne-Edwards theory of population regulation. A mutation may arise in the population that predisposes a bird to lay six eggs for instance instead of two. If there are enough resources for these six individuals to survive then the genetic tendency to lay six eggs will be passed on. It would not take many generations of six egg-laying individuals to over exploit the resources.

Answer 8

The ‘answer’ is that the unit of selection is the gene. This was proposed by Bill Hamilton in a legendary paper published in 1963 in The American Naturalist and then in a longer paper published the following year in The Journal of Theoretical Biology. Ignored at first, then the idea took off in the 1970s. Now it’s the most famous and significant paper/idea in evolutionary biology and its this that started the revolution (in evolutionary biology).

Answer 9

A gene will influence the body it sits in to behave altruistically towards other animals that share that gene. If a gene could talk it would say: “To propagate myself as much as possible, I need to help other individuals who are closely related because a copy of myself resides inside those individuals”. This is known as ‘kin-selection’ or ‘inclusive fitness’. In other words, if an animal has a gene which leads the animal to behave in an altruistic way to a relative (who is likely to also have that gene), the gene will spread through the population. Genetically speaking, one individual is equivalent to two siblings, or four cousins etc. Each is worth as much. That is, one individual has 1 gene (of course) for a certain trait; two siblings have the equivalent of 1 gene because there is a 50% chance of that one individual’s gene being in one of the siblings. Another example – one individual has 1 gene for a certain trait; 4 niece/nephews have the equivalent of 1 gene because there is a 25% chance of that one individual’s gene being in one of the 4.

Answer 10

A gene coding for an altruistic act will be selected if the cost to the individual is less than the benefit gained by the recipients of the altruistic act. That is, if the benefits of the altruistic act outweigh the costs, then selection will favour the behaviour. ‘Benefits’ and ‘costs’ are measured in terms of ‘fitness’, i.e. reproductive success. The fitness of a behaviour therefore is determined by the direct effect of the behaviour on the fitness of the individual, as well as the summation of indirect fitness effects across all kin that are affected, and, importantly, adjusting for the degree of relationship of the kin. Hamilton expressed his idea in a simple mathematical formula that describes the concept of ‘inclusive fitness’ (i.e., ‘kin selection‘): The gene for acting altruistically will be selected if: - C < B X R Where C is the cost to the altruist, B is the benefit to the recipient/s R is the degree of relatedness between the altruist and recipient/s.

Answer 11

“For the good of the group” – No. A defector will always do better. For the good of the individual – No. Altruism exists. For the good of the gene – Yes. A gene that predisposes an individual to act altruistically (i.e., scan for predators) will spread. It will be selected. It is a ‘selfish gene’. Its selfishness has generated altruistic behaviour.

Answer 12

Altruism is only one aspect of a gene’s ‘goal’: to replicate itself as much as possible; to dominate the gene pool; to be ‘selfish’. Altruism is an addition to the most obvious way a gene can replicate itself: Influence the body it sits in to act in a way that ensures the body survives to pass on copies of the gene. Thus, make it good at avoiding predators; good at finding food; finding a mate (doesn’t find a mate, it will not be replicated), finding shelter, making good webs if it’s a spider, good vision if its an eagle. etc etc…

Answer 13

i.e., there are many genes influencing behaviour. Dawkins (Chapter 3) gives the example of an oarsman who realises that a particular crew member tends to be in the boat when fast times are recorded. (The same principle as isolating one factor amongst many in a standard psychology experiment).

Answer 14

Hymenoptera sex ratios: Hamilton said that it is no coincidence that the extreme example of altruism is seen in the Hymenoptera (e.g., wasps, bees, ants). In these species, most famously in the bees, ‘workers’ don’t reproduce they cooperate with fellow workers. Its no coincidence because females share a greater proportion of their genes with their sisters (75%) than their own daughters (50%).

Answer 15

“If one or two of my brothers were drowning in this river, I might perhaps not risk my life to save them but if more than two of my brothers were drowning, I might attempt to save them at a risk to my life”.

Answer 16

Essentially, behavioural ecologists work out what the most efficient behaviour is in a certain situation and then examine whether animals perform this ‘optimal’ behaviour. Or, similarly, they observe what animals actually do and work out whether this is the most efficient way of performing that goal.

Answer 17

Which line should I queue in? The line with three half baskets or one full trolley? We essentially perform a cost/benefit analysis. The cost = larger queue. The benefit = less items to check-out. The net result is the time it takes us to pass through. In this situation, we tend to apply something akin to Hamilton’s formula... Remember that ‘Hamilton’s rule’ is mathematical (We could empirically assess whether humans act optimally in this situation. i.e., find out what the best strategy is and see if humans do it. But remember, humans are likely to be thinking consciously, animals are not). Costs and benefits weighted against each other are central to the Selfish Gene theory and thus the notion of optimality.

Answer 18

Each individual animal can expect to hunt for 40 minutes in order to eat a complete prey item. We could go into the field and test this. i.e., Find out what the most efficient strategy actually is, by observing the different strategies (if there are different ones), and see if lions adopt it.

Answer 19

Doesn’t the Selfish Gene predict that offspring number will keep on increasing? No. “All models of the evolution of family size assume that there is a trade-off between the number of progeny produced and the fitness of each of them” (Krebs & Davies, 1978). This is empirically true…. Similarly, number of offspring relates to survival rate. Clearly a negative relationship, and the principle of dividing one’s resources too thinly.

Answer 20

The great ornithologist of the 1950s and 60s David Lack first argued that birds do. Suggested that those who laid the optimal number of eggs would leave the most offspring. He undertook a long term study of the great tit in Wytham woods, near Oxford (the work was followed- up by Perrins). This population lay a single clutch of 8-9 eggs Following Lack, researchers have employed a basic paradigm for assessing whether birds lay optimally. Add (or take away) eggs from a nest and see whether this manipulation increases offspring success. If birds are acting optimally, such manipulation should not increase success. Put another way; determine which is the most efficient clutch size number through experimental manipulation and see whether this number is what a bird actually lays. This figure shows the optimum brood size based on survival from egg number manipulation experiments. The optimum of 8-11 is close to the real figure of 8-9 but is a bit more, i.e., the birds appear to be laying below optimum. Although, these data suggest that about 8 is optimal in the great tit. It supports the actual number they lay. (The ‘recaptures per brood’ measurement may not be the most appropriate. It may not take into account more long-term success. Remember a basic principle of behavioural science; the dependent measure is important).

Answer 21

Charnov and Krebs (1974) suggest a reason why birds underestimate their brood breeding ability. The probability that a parent will survive to breed the following year is also dependent on brood size, the larger the brood size the smaller the chance of survival (extra work, etc)……… So the parent should not just consider its optimum output for one brood for a single year but for all its broods over its entire lifetime.

Answer 22

An anti-predation effect without increased vigilance. Water skaters sit on the surface of ponds and are predated by small fish. Attack rates do not differ with size of group. But, predation is still lower per individual as group size increases. There is just less chance of being one of the unlucky few (Foster & Treherne, 1981). A dilution effect was empirically supported by Duncan and Vigne (1979) in the semi-wild horses that live in the marshy delta of Carmargue in southern France. In the summer the horses are plagued by biting tabanid flies. The horses form groups. Measurements of tabanid numbers showed that there were less per horse for larger groups compared with smaller groups. This was confirmed by an experiment in which horses were transferred between smaller and larger groups and vice versa.

Answer 23

As well as benefits to groups there are clearly costs of larger groups. Increased competition for food. Increased incidence of disease as a result of close proximity with others, (Hoogland, 1979). Brown and Brown (1986) showed that larger colonies of cliff swallows have more blood sucking swallow bugs per nest than smaller colonies.

Answer 24

Has been the main concern of optimality theory. The rationale is very simple: Economically define an optimal strategy for finding and eating food then observe animals to see whether they do indeed act optimally. Again, the assumption is that natural selection chooses the best strategy for eating food. “Let us assume that natural selection will favor the development…. of feeding preferences that will…..maximize the net caloric intake per individual of that species per unit time”. Zach, (1979) optimal foraging in Northwestern crows on the coast of Canada. Feed on whelks. Drop them on rocks in an attempt to smash them open. A basic trade off exists between height and success. Is there an optimum for breaking open shells? Yes.

Answer 25

e.g., shore crabs The larger the muscle the more calories it contains. It would therefore seem to make sense to eat the largest muscles. However, the relationship between size of muscle and effort required to open it is not likely to be linear. However, whilst they avoid the very large and very small muscles, they don’t just eat muscles between 2-3 cms, they eat many smaller and many larger. Why? What does the crab have to take into account? It has to consider search time. Little point in wasting energy by searching for the most profitable muscles if you don’t come across them that often. You might as well take the one which are not quite optimal as well.

Answer 26

Decisions such as these (i.e., when to reject a prey item) is inherent in Charnov’s Prey Model. Charnov proposed that foraging involves a continuous cycle. 1. The search. This includes any activity that involves looking for food. 2. Occurs once a prey item has been found. Should this prey item be perused? Thus the cycle is one of search, encounter, and decide. The critical information that the animal needs to ‘know’ is: 1. The energy gained from eating a particular prey. 2. The energy cost in searching for a particular type of prey and catching it, called the handling time. 3. How often is particular prey item likely to be encountered. The third one is important because this will affect 2. It’s essentially a cost-benefit analysis for each prey type.

Answer 27

A simple model of competition: Two habitats, one is rich in resources the other poorer. An animal will chose the former, later arrivals will do the same. However, as more animals use the habitat the resources will be depleted making it less profitable to latecomers. Eventually a point will be reached where late arrivals will do better occupying the ‘poorer’ location, where although poorer in resources, there is less competition. Thus an equilibrium will be reached where the two habitats will become equally profitable per individual (containing more individuals in the rich habitat).

Answer 28

1.A behaviour may not be adaptive, (i.e., is not ‘functional’; not due to evolution; More on this in Lecture 9). 2) If a behaviour is found not to be optimal other explanations are easily at hand: The wrong units of optimising were used; the experiments were not done well enough; the model is wrong. 3. One of the issues is what units of fitness success are appropriate. 4. The general problem of adding factors in modelling. Take optimal group size. Optimal behaviour is going to depend on many interacting factors….

Answer 29

Will clearly depends on many factors. Pulliman (1976) and Caraco et al. (1980) attempted to model the main factors (feeding, fighting, scanning). Other factors include the behaviour of other animals, as this shows. Also, the changing ecology (i.e., environment) will be another factor in any optimality model. Optimal copulation in Dungflies. This will also depend on many factors. Recall that the data suggested that he should stop when the line starts becoming more horizontal than vertical (i.e., at about 45 minutes). However, it may be more optimal to carry on mating if the chances of finding another female are low. The additional factor here is the search time to find another willing female. Or, consider our first example where humans act consciously Which line should I queue in? The line with four half baskets or one full trolley? We essentially perform a cost/benefit analysis: We often take into account many other factors. e.g., Speed of the check-out assistant. ‘He/she seems to be talking a lot’. ‘What kind of items are actually in the baskets and trolley’? (to be fair, this last issue occurs with all theory generation, i.e., adding factors).

Answer 30

A game theoretic approach should be used to understand the behavior of animals whenever there are reasons to believe that the strategy or the behavior of one organism is affected by the behavior of the other and vice versa.

Answer 31

The critical difference between the standard use of game theory and Maynard Smith’s application was that whereas human are conscious of a strategy, animals are not. An animal will ‘choose’ a strategy in a Darwinian sense; the best strategy will presumably be selected. Just like the most optimal strategy for foraging is likely to be selected.

Answer 32

Remember the main issue from the selfish gene lecture? How can altruism evolve given; 1) The potential cost of assisting others, 2) An individual will always do better by not co-operating. e.g. alarm calls and group surveillance. The answer? The unit of selection is said to be the gene. A gene predisposing an individual to act altruistically will propagate itself (i.e., be selected) by assisting kin. Geoff’s model of ‘Hamilton’s rule’ What about 3 siblings (who each have a 50% probability of sharing that gene with the altruist)? The gene will increase in frequency in the ‘gene pool’. .5 X 3 is greater than 1.

Answer 33

(known as reciprocal altruism) Many examples.....e.g., cleaner fish Approximately 50 species of fish feed by picking parasites off the body of larger fish. The larger fish recognise a cleaner as such and refrain from eating it. The answer has come from a model based on one aspect of Game theory known as the ‘Prisoners Dilemma’.....

Answer 34

The prisoner's dilemma is a game theory thought experiment that involves two rational agents, each of whom can cooperate for mutual benefit or betray their partner for individual reward. This dilemma was originally framed by Merrill Flood and Melvin Dresher in 1950 while they worked at the RAND Corporation. Transport is a good example with people taking a train or bus. And people defecting and using cars for their own transport, creating more CO2.

Answer 35

Many animals are caught in a Prisoners Dilemma. e.g., the large cleaned fish. Tempting for the cleaned fish to ‘defect’ and get an easy meal. Why don’t they? How could reciprocal altruism evolve? Need to know whether co-operating in this way is an optimal strategy ‘Tit for tat’ was the most successful (submitted by psychologist and game theorist Anatol Rapoport): The player starts playing C and then plays whatever its partner did in the previous move. Classified as a ‘nice’ strategy. Axelrod published the results of the first competition and announced a second competition. 62 entries were submitted. Once again tit for tat won. Tit for tat is the same as grudger and the notion of reciprocal altruism. In sum, this computer model shows that reciprocal altruism can evolve because it is the best strategy.

Answer 36

Imagine a species of bird who are parasitized by ticks. The birds can remove their own apart from the ones on the top of the head. They must rely on each other to remove the head ticks. Birds can employ one of two strategies: Sucker – remove other birds ticks Cheat - don’t remove other birds ticks Cheats will always do better. They will come to dominate the population.

Answer 37

Many animals and plants reproduce either sexually or asexually. The former is characterised by the division of sex cells (meiosis) from two different individuals which then fuse (syngamy) producing offspring that contain genetic material from two parents. In the latter, parents produce exact replicas of its own genetic material. Why has sexual reproduction evolved as the dominant system? No one knows. But: it has the ability to eliminate harmful mutations - only a 50% chance of them being passed on. 100% with asexual reproduction.

Answer 38

i.e., what is the definition of a male animal and a female animal? Can’t use the obvious. The defining distinction is often taken to be the relative size and number of the sex cells (‘gametes’). One group of individuals of a species has relatively large and a small number of sex cells, whilst the other group has relatively small and numerous sex cells. These are then referred to as female and male.

Answer 39

Contrasts Isogamous sexual reproduction in which the sex cells are of similar size and morphology. How did Anisogamy evolve? Parker et al.(1972) presented a popular theory. Basic premise - the larger the sex cell the more likely it is to survive (e.g., has greater energy/food resources). Thus a selection pressure existed for large sex cells. But, smaller sex cells will also have an advantage over the medium size cells because they can more easily fuse with larger ones. Consequently, the sex cell population becomes dominates by two forms of sex cell - few but large and numerous but small. Intermediate sized sex cell has no advantage.

Answer 40

The best strategy is to produce an offspring that is in the minority. Fisher’s explanation is sometimes reflected in this puzzle… Image there are 2 islands. One has 10 males and 90 females. The other has 90 males and 10 females. If we went to the islands in 150-200 years time which island will have produced the most offspring and what approximately will the sex ratios be on each island? Fisher’s explanation is known as frequency dependent selection. i.e., the best strategy to employ depends on what everyone else is doing. Do the strategy that relatively few are employing may be the best thing. Fisher’s argument also supports the notion that animals do not behave for ‘the good of the species’. If only they would all agree to a sex ratio of 1 male to every 100 females they would do much better collectively than the ratio of 50:50. This explanation is also an example of an Evolutionary Stable Strategy we came across last week....

Answer 41

Placed 5 male and 5 female fruit flies in a chamber and let them mate with who and how often they wanted. Females each had about the same number of offspring regardless of how many partners they had. By contrast, there was large variation in the number of offspring the males had. "While males had more children the more partners they mated with, females did not“. Thus, whilst females gain nothing by mating with more partners males do. A single male white-bearded manakin obtained over 80% of matings in one breeding area in one season (Lill, 1974). Is observed in many species (Hoglund & Alatalo, 1995). “Among polygynous species, the variance in male reproductive success is likely to be greater than the variance in female reproductive success." (Huxley 1938). Bateman concluded that his results suggests that this would produce ‘an undiscriminatory eagerness in the male and a discriminatory passivity in the female’. "The female, with the rarest exceptions, is less eager than the male... she is coy, and may often be seen endeavouring for a long time to escape." (Darwin 1871).

Answer 42

Related to Bateman’s principle is the idea that females ‘invest’ a lot in offspring whilst males don’t. The result: the sex that invests more in a potential offspring can be very choosy in a mate and highly discriminative. By contrast the sex that puts little effort into reproduction cannot be choosey and will be very eager. Given that males vary in their reproductive success (and invest little) they should compete heavily to win a female. E.g., be more aggressive and more salient.

Answer 43

Good evidence for the idea that the disparities in male/female investment leads to differences in the behaviour of each comes from ‘sex-role reversal’ in the seahorse. Male seahorses undergo pregnancy rather than the females. The male has a pouch in which the female deposits her eggs, which the male fertilizes. The young then develop in this pouch. Consequently, it is the females who compete for males. They are more aggressive and coloured. Sexual selection: Although Darwin’s theory is often referred to as ‘survival of the fittest’, its ultimately concerned with reproduction than survival. This, Darwin argued, can explain why some evolved traits appear to hinder survival rather than promote it. “depends, not on a struggle for existence, but on a struggle between the males for possession of the females; the result is not death to the unsuccessful competitor, but few or no offspring”

Answer 44

The basic principle of Bateman and PIT (i.e., males vary in their reproductive success, females don’t) leads to the Trivers-Willard hypothesis. Is a general strategy of reproduction for either sex based on the condition of parents. Parents of little resources or are in poor condition should invest in a daughter not a son. No matter what condition a daughter is in she will find a mate, but a poor condition son won’t.

Answer 45

The best parental investment strategy is to ‘desert’ (i.e., leave the partner to rear offspring). A consequence of PIT is that the sex that invests least in offspring is more likely to ‘desert’. Usually the male. Maynard Smith (1977) provided a number of mathematical models of male desertion. Model 1 includes the 2 main parameters that he needs to take into account when considering desertion. 1. The likelihood of 0, 1, and 2 parents successfully raising young. 2. The likelihood of finding a new mate. “That is, desertion is favoured if there is a good chance of finding a second female, and if one parent is almost as good as two in caring for offspring”. Maynard Smith applied the model to real species and ecologies. In particular he contrasts male desertion in mammals and birds. He noted that in mammals, it is the females who tend to feed the young. In other words, young do not rely so much on the father. Similar to Example 1; he deserts. Birds by contrast do not lactate. Thus, the young reply on both parents. Similar to Example 2; he stays.

Answer 46

Entering differing values into the model is equivalent to different ecological scenarios. This will tell us when desertion is a good strategy (or not). Imagine an animal (and ecology) in which offspring need little care (e.g., those species that lay 1000s of eggs and hope that some survive) and the probability of finding a new mate is high. V1 + pV2 > V2 8 + (.7 x 10) > 10. In other words, when the male’s (deserted) partner can raise 8 young alone (as opposed to 10 when he stays), and there is a 70% chance that the male will find a new partner he should desert. Or to put it another way: there is little difference in the number of offspring his partner can raise when he stays (10) as opposed to deserts (8). And, he has a good chance of finding a new mate. V0 = the number of offspring per pair when both desert. V1 = the number of offspring per pair when one parent stays. V2 = the number of offspring per pair when both parents stay. p = the likelihood of finding a new mate if he deserts.

Answer 47

As we have seen, PIT suggests that it is the female who can drive a hard bargain and the males must compete to attract females. Given this imbalance of power what is the best strategy she can employ in terms of optimising her offspring quality and number? There exists a number of ideas: 1.Good genes 2.Sexy son hypothesis 3.Madame Bovary 4.Domestic bliss 5.Could also mate choice copy.

Answer 48

The female only copulates with the best males. She goes for the best genes, and accepts that she will receive no help from the father. She is not concerned that the male may be copulating with other females. What will she be looking for? Speaking generally, the female would look for evidence of ability to survive and reproduce. With respect to survival she may therefore be attracted to older mates.

Answer 49

Mostly associated with Zahavi’s (1975) ‘handicap principle’. Selecting for good genes could lead to the evolution of fake qualities could evolve. Optimally, it is a better strategy to grow fake muscles than real ones. Nature will therefore select individuals who can show off real qualities, ones that cannot be faked. A real quality is where a male has a handicap. Females are more likely to choose males who possess a costly handicap. If such a male has survived despite his handicap he must possess good genes. Most famous example is the peacock’s tail. Others include, the tail of the birds of paradise & Deer antlers.

Answer 50

If having a larger tail does not have any reproductive benefits then the tail cannot have evolved for reproductive reasons. Petrie et al. (1991) showed that there is indeed a positive correlation between the number of spots on a peacock’s tail and the number of mates it attracted……… …..more spots could mean greater likelihood of winning a fight with another male (e.g., more frightening). The winner is then more likely to mate with a female. Petrie (1994) assessed this by taking 8 males and placing each in a pen with 4 randomly chosen females. Thus, no competition – each male mated with each of the 4 females. Results showed that the weight of the young and their chances of surviving to 84 days of age was positively correlated with mean area of the father’s eye spot…..

Answer 51

First put forward by Weatherhead and Robertson (1979; following Fisher, 1930). Suggests that a potential mate's capacity to be a father are not considered. Instead, the female should choose a male whose genes will produce male offspring with the best chance of reproductive success. In other words, a female may benefit from pairing with an already mated-male if her sons inherit their father’s attractiveness. Choosing an attractive male will result in an attractive son.

Answer 52

Obtain good genes from the appropriate male (as discussed above) but dupe a ‘domesticated male’ to help rear them.

Answer 53

She looks for males who exhibit signs of fidelity and domesticity. E.g., building a nest represents a direct investment by the male in the eggs. Trivers (1972) argued that she can make the male invest a lot before copulation in order to reduce the risk of his desertion. But: economists have long known that this is not optimal behaviour. (remember that optimality theory in animal behaviour incorporates economics and mathematics). Do animals consider the effort already made…..?

Answer 54

Dawkins and Carlisle (1976) first raised the point that Trivers had made an erroneous assumption of males saying: ‘I’ve invested too much’. Arkes and Ayton (1999) define the effect as ‘a maladaptive economic behaviour that is manifested in a greater tendency to continue an endeavour once an investment in money, effort, or time has been made”. In human terms this is best expressed in the common saying “I can’t quit now, I’ve already invested too much”. This however is economically fallacious. Economists have known for a long time that one should never say this to oneself. Instead, one should say “what will be my return given the amount of effort put into the project from this point forward. Do non-human animals behave as if they take into account the effort they have already put into obtaining a particular goal? i.e., do they commit the Concorde fallacy? In theory they should not. Why shouldn’t they? In other words what is the rationale for assuming that lower animals should not commit the Concorde fallacy? Committing the fallacy is not optimal behaviour. Arkes and Ayton (1999) relate the example of a parent animal that has 2 offspring and food/resources become short. One offspring is older, the other is a newborn. Who should the parent invest the limited resources in? Should the parent feed one or the other based on the fact that he/she has already invested a lot in that offspring – No. That would be committing the Concorde fallacy. The parent should choose the older one, not because of the effort already invested, but because the older one will require smaller effort in the future to produce a survived offspring.

Answer 55

These wasps dig burrows for their developing larvae. Takes around an hour and a half (Brockmann et al. 1979). Is therefore energy/time consuming. Fierce fighting occurs between ‘diggers’ and ‘squatters’. Fight ends when one of the wasps concedes defeat. Suggests the winner fought harder because she had made the greater prior investment in the nest.

Answer 56

Little evidence has however been found for effects of prior investment on present/future behaviour. E.g., litter defence behaviour of female albino mice (Maestripieri & Alleva, 1991) . On the 8th day of the mothers lactation period a male intruder was introduced. 2 critical groups being tested. In both groups the litter size was culled from 8 pups to 4. In the first group this happened at birth whilst in the second group this happened 3-4 hours before the intruder was introduced........... Rationale: If the mice commit the Concorde fallacy the mother of the litter culled 3-4 hours ago should exhibit more defensive behaviour than the mother of the culled at birth group. This will be because the mother of the culled 3-4 hours ago group has invested more in rearing her 4 pups. (By contrast, the mother of culled at birth group has not invested as much in her 4 pups). Maestripieri & Alleva (1991). Results showed that there was no difference in the level of defence exhibited by the mother in either group. i.e., no Concorde fallacy committed.

Answer 57

A female needs as much information as possible to decide who to mate with. May help to know that others have decided that a particular male is worthy. Also, (related), there is always a cost to doing a certain behaviour. It takes time and energy/effort to find a mate. Why not reduce costs and copy others? Alan Lill (1974). Studied the mating behaviour of the white-bearded manakin bird (in Trinidad). Noted that in one breeding season a single male obtained the majority of matings (80%). This is a common phenomenon particularly in Lekking species (Hoglund & Alatalo, 1995). Lill suggested that females might be copying each other’s choice of mates. However, all the females who mate with the dominant male may be choosing him independently of the others. That is, he may have some feature that all the females are attracted to regardless of what the others think.

Answer 58

Flowers demonstrate ‘kin recognition’. The English plaintain grows faster when near to kin than non-kin (Pfennig & Sherman, 1995) The plants are thought to release chemicals via roots to enable discrimination. Grosberg and Quinn (1986) Tunicates (Sea squirts) have no brain. They settle on a rock and produce asexually. Sometimes two genetically related colonies will fuse (at the larvae stage). If a tunicate attempts to join an unrelated colony, the hosts emit a toxic substance that repels the invader. In breeding experiments, the authors showed that unrelated individuals will fuse if they share the same single ‘KR gene’.

Answer 59

Explicit in Hamilton’s idea is that the likelihood of acting altruisitically towards an individual is based on the degree of relatedness. Genetically speaking, one individual is equivalent to two siblings, or four cousins etc. Each is worth as much. That is, one individual has 1 gene (of course) for a certain trait; two siblings have the equivalent of 1 gene because there is a 50% chance of that one individual’s gene being in one of the siblings. Another example – one individual has 1 gene for a certain trait; 4 niece/nephews have the equivalent of 1 gene because there is a 25% chance of that one individual’s gene being in one of the 4.

Answer 60

Immelmann (1959) Painted the black bills of juvenile zebra finches red as possessed by adults. Adults would not feed the young despite their intense begging. Beak colour must therefore be the critical recognition feature (‘releaser’) that tells parents who the young are.

Answer 61

Often said that a KR system requires several key components or design features. 1. A ‘sender’ must exhibit kinship cues (markers, labels, signatures, tags). Can be visual, chemical, acoustic, etc. 2. Recognition begins with sensory detection (perception) of the cues by a receiver. 3. A matching process needs to occur in which the sender’s cues are compared with a template. This template can be learned either from ‘self-inspection’ or from other referents (relatives). 4. A behavioural effect must sometimes follow (but not always). i.e., discrimination.

Answer 62

Problems of different meanings: Early work, and later interpretations, suffered from the problem of what researchers actually meant when they referred to ‘kin recognition’. Early researchers (e.g., Holmes & Sherman, 1983) tended to mean KR in a way the behaviourist/empiricists would mean it. i.e., differential treatment based on degree of relatedness (Corresponding to Key Component number 4, with numbers 1-3 not necessary). Became ‘kin discrimination’. “Kin discrimination refers to the differences in behavioral responses that an individual shows towards its kin as compared to non-kin” (Tang-Martinez, 2001). Later researchers meant internal processes with no reference to differential treatment (Key Components 2 and 3). Became ‘kin recognition’. And of course one process or component can occur without the others. E.g., Recognition may occur but with no subsequent behavioural output (i.e., no discrimination). “just as recognising a fruit as an orange does not necessarily lead us to eating it” (Barnard, 1991). And, discrimination may occur when there is no understanding of the ‘cognitive’ or neural processes involved.

Answer 63

In a review of KR, Waldman (1988) made the distinction between ‘direct’ and ‘indirect’ recognition. Direct: Kin are recognised because the observed animal expresses some observable trait (a phenotype) or set of traits. Indirect: Non-phenotype cues are used. Kin are recognised based on some environmental context rather than something about the observed animal per se.

Answer 64

Most behavioural ecologists however suggest 4 categories of KR. 1. Context-based recognition 2. Prior association 3. Phenotype matching 4. Recognition alleles

Answer 65

Also known as ‘ancillary kin bias’, ‘non-discriminatory kin bias’, ‘kin biases without kin recognition’. Has not been the subject of as much empirical investigation as the other 3. Context-based KR is mostly concerned with space-based recognition. Holmes and Sherman (1982) found that Belding’s ground squirrel mothers would retrieve into their burrow unrelated young, but not after their real young had reached 25 days old. Could evolve if all (or at least most) the individuals within a location will be related to the observer. For instance, species in which littermates always stay close to home when juveniles (e.g., bank swallows). Similarly, could also evolve in species where non-kin have no access to the kin area. Thus, a parent will know that the offspring are kin. Is however, open to exploitation, as occurs with the cuckoo.

Answer 66

1. Time spent mating I didn’t spend much time alone with female X but I did with female Y. I should invest more parental effort in the offspring of female Y”. Male Dunnocks adjust their parental investment based on how much time they spent alone with a female during the mating period (Davies et al, 1992). 2. When mating occurred “I can only be related to these offspring if I met the female before she started incubating”. Male Tree Swallows will invest in offspring if they are experimentally introduced during the mating period but will not do so if they were introduced during incubation.

Answer 67

Thus, animals learn some observable characteristic or trait (‘phenotype’) possessed by kin members (parents and siblings) during early development. Relies on dispersal being delayed (or rapid learning). And, non-kin not being encountered very often during development. E.g., nest sites. Otherwise, recognition errors will occur if non-kin are encountered (i.e., a Type I error). Cannot distinguish between equally familiar but unequally related individuals.

Answer 68

The first study to examine KR within the context of kin selection theory. Used physical contact (‘huddling preferences’) in Spiny Mice as an index of recognition/preference. Results showed that the test animals preferred siblings. Also found that if the test animal was housed with non-kin only animals for 5 days, it then preferred non-kin. Supports the notion of a ‘sensitive’ period and imprinting

Answer 69

Prior association necessary? Researchers soon began to ask whether previous association was needed for KR to occur. Can an animal recognise another animal as kin when they have never met before? Unfamiliar kin? With this system, it was hypothesised that animals learn certain features possessed by itself or parents and siblings and these are compared with the animal present. This paradigm cannot be used to assess recognition of unfamiliar kin because the offspring were in contact with each other in the early stages of life. Recognition of unfamiliar kin can be tested via controlled breeding. E.g., half-siblings vs non-kin (such as a half-brother or sister).

Answer 70

The first study to examine and report recognition of kin never seen before. It also manipulated degree of relatedness. Thus directly tests Hamilton’s theory. Female sweat bees guard the entrance to the nest. Only nest mates allowed in. Unfamiliar ‘intruders’ attempted to gain entry. Through controlled breeding these intruders were related to the ‘guards’ to various degree. The likelihood that an intruder would be allowed in increased with increasing genetic relatedness.

Answer 71

How can this occur? ‘Self inspection’ is one hypothesis. This is the ability of animals to learn some aspect of themselves (i.e., their own phenotype) and compare these traits with others. The ‘armpit’ effect (Dawkins, 1982). Is only likely to occur in species that can use odors or sound cues, since visual cues would require some way of seeing oneself. Some (e.g., Waldman, 1987) argue that recognition based on phenotype matching is in fact a misidentification error. One cannot, by definition, recognise a stranger.

Answer 72

Hamilton (1964) suggested the possibility of a supergene that could enable direct recognition of itself in others. Dawkins (1976) named it the ‘green beard effect’. Hamilton (1964) stated that the supergene would work by encoding three traits: Influence the expression of a rare phonotypic trait. Enable individuals to recognise the trait in others. Cause the carrier to act altruistically to others who possess the trait. Is largely a theoretical possibility rather than one that has a body of evidence to support it. Main argument against it concerns the unlikelihood of a single gene coding for three very different effects.

Answer 73

A central issue is that a KR system must optimise the risk of acceptance and rejection errors. Acceptance errors are where an animals accepts non-kin as kin, i.e, a Type I error (false positive). Rejection errors are where an animal rejects kin that are kin. i.e., a Type II error (false negative). “..acceptance thresholds should not be underestimated.” (Penn and Frommen, 2010). There is a balance between acceptance errors and rejection errors, and two ends of a continuum. The best strategy may depend on ecological circumstances. One extreme strategy: “Only accept if you are absolutely certain the animal is kin”. The other extreme strategy: “Accept most animals. Don’t be too concerned if you accept a few non-kin. Non of your real kin will be rejected” Cuckoldry is a clear example of a Type I error.

Answer 74

As we have seen, KR has been investigated very much within the context of ‘inclusive fitness’, i.e., Hamilton, the Selfish Gene. Remember this earlier sentence: Explicit in Hamilton’s idea is that the likelihood of acting altruisitically towards an individual is based on the degree of relatedness. It has therefore been argued (usually implicitly) that there must exist an evolved mechanism for recognising kin, i.e., a module. A ‘module’ is a mechanism that has evolved to perform a specific job (see also Lecture 8).

Answer 75

There is a mechanism and module for recognising objects, and it has a location. The fusiform gyrus and adjacent areas are dedicated to recognition. Importantly, this mechanism seems to be concerned with all classes of objects, i.e., it is not specialised for one. At best, it may separately be concerned with faces and objects. But, in all the hundreds of reports of object agnosia, none report a deficit specific to recognising kin (even Capgras).

Answer 76

Probably via the same mechanism that enables (visual) object recognition in humans and all organisms. Thus involves the same processes and problems. E.g., A major problem of O.R. is that of ‘object constancy’. The spatial distribution of light intensity on the retinas can vary enormously when viewing the same object…….

Answer 77

A generalised system that enables KR to occur (i.e., the basic visual system) will also enable individual recognition for non-kin reasons. Mate choice, dominance hierarchies, reciprocal altruism, self protection Thus, social recognition abilities have evolved for a variety of function reasons. “That individual never shares food”, “They are aggressive”, “They are higher in the Peck order”, “They never respond to my sexual advances”.

Answer 78

Men hunted and women gathered during the Pleistocene era. 2) There was a selection pressure for abilities associated with each role resulting in the evolution of these traits. 3) Today’s sexual division of labor (men work, women at home) is due to this evolutionary past.

Answer 79

Silverman and colleagues argued that certain skills would have facilitated hunting such as good navigational ability, which is better in men. By contrast, women as gatherers should perform better on object location memory tasks. Stoet argued that women should be better than men at visual search. But, men as hunters would have had to search too. Predictions should only apply to one sex or the other. One example is the ability to detect movement. Men should be better at this. And, this effect should be more pronounced in far as opposed to near visual space. The near/far prediction was supported by Sanders et al. (2007).

Answer 80

Cosmides & Tooby (e.g., 1992) argued that this model dominated the social sciences throughout the 20th century up to the 1970s and contained two main assumptions. 1. The mind of the new born is content-free, or is a ‘blank slate’. “The idea that the mind is an empty sponge waiting to be filled is one that pervades both our everyday thinking, and much of academia”; Mithen, (1996). This model dominated partly because of ‘behaviourism’ and for political reasons. The notion that human nature is innate has always been controversial. E.g., Eugenics movement, social Darwinism, WWII. 2) The mind possesses an abstract general purpose learning mechanism.

Answer 81

Like physical traits, the mind, cognition and behaviour have been shaped by evolution whereby nature has selected those cognitive capacities which have resulted in a reproductive benefit. “the human mind evolved under the selection pressures faces by our human ancestors as they lived by hunting and gathering in Pleistocene environments”. Mithen, (1997). Nature has selected the most efficient psychological traits and behaviour which help to maximise the propagation of one’s (selfish) genes.

Answer 82

The mind consists of ‘mental modules’ which evolved to solve specific adaptive problems that our ancestors faced in their environment of evolutionary adaptation (EEA). “the mind consists of a Swiss army knife with a great many, highly specialised blades; in other terms, it is composed of multiple mental modules. Each of these blades/modules has been designed by natural selection to cope with one specific adaptive problem faced by hunter-gatherers during our past….the mind has more than a capacity for ‘general intelligence’ – there are multiple specialized types of intelligence, or ways of thinking”.

Answer 83

Evidence suggests that body/face symmetry is a good indicator of health. Various environmental events and genetic stressors cause deviations from bilateral symmetry. Symmetrical faces are particularly attractive.

Answer 84

Tooby, Cosmides and colleagues suggest that we have an innate mechanism to detect cheaters. This is reflected in our reasoning ability. They argue that since humans have engaged in social interaction for over a hundred thousand years, our minds should have evolved cognitive adaptations for social life. Tooby and Cosmides investigated this with the ‘Wason selection task’.

Answer 85

The Wason selection task is reasonably difficult. Only about 20% of the population give the correct answer. However, Tooby and Cosmides applied the problem within the context of social exchange where the detection of cheaters is involved. With this variation they hypothesised that the task will now be easier because humans have a domain specific module for the detection of cheaters. Tooby and Cosmides found that when this new variation of the problem was applied (i.e., within the context of social exchange where the detection of cheaters is involved) the proportion of people who gave the correct response rose to 75%. Thus, confirming their hypothesis. Importantly, both the original Wason task and their variation are logically identical. One might argue however, that the difference in results is because people are simply better at reasoning in a non-abstract context and people are very familiar with bars and drinking. Tooby and Cosmides assessed this potential argument by performing further variants of the Wason task.

Answer 86

If a ‘cheat detection’ module does exist one should expect other components of the mind (in addition to problem solving) to be sensitive to cheats. Mealy at al (1996) assessed whether memory for faces is enhanced by knowledge that the face belongs to a cheater. They presented 124 participants with photographs of 36 males. Each photo was supplied with a brief fictitious description of the person. This information subtly stated whether the person was a cheater or not. A recognition test was given to the participants one week later. Both males and females were more likely to remember a cheat rather than a trustworthy face.

Answer 87

Arkes and Ayton (1999) define the effect as ‘a maladaptive economic behaviour that is manifested in a greater tendency to continue an endeavour once an investment in money, effort, or time has been made”. This is best expressed in the common saying “I can’t quit now, I’ve already invested too much”. This however is economically fallacious. Economists have known for a long time that one should never say this to oneself. Instead, one should say “what will be my return given the amount of effort put into the project from this point forward. Remember the question: Do non-human animals behave as if they take into account the effort they have already put into obtaining a particular goal? i.e., do they commit the Concorde fallacy? In theory they should not. Committing the fallacy is not optimal behaviour. In humans the Concorde fallacy is often called the ‘Sunk-Cost effect’.

Answer 88

Seems to be yes. For instance, Staw and Hoang (1995) found that professional basket ball coaches gave more playing time to players who had cost the team more money. Arkes and Blumer (1985) set up an experiment in which people who bought a season ticket for the university theatre would be sold one of 3 tickets :- $15, $13 or $8. Those who had bought the dearest season ticket attended more plays then the other two. Presumably they had taken into account their prior investment.

Answer 89

Lorenz suggested that one way to reduce human aggression is to engage in aggressive behaviour. Furthermore there will come a time - according to the model - when aggressive behaviour will be exhibited in the absence of any provoking stimuli – vacuum activity. “the subject of this book is aggression, that is to say the fighting instinct in beast and man which is directed against members of the same species”.

Answer 90

Aka, Panglossianism, Or the adaptationist paradigm. What is the adaptive significance of males going bald? What about blood being red? Bones being white? Adaptationism (also known as functionalism[1]) is the Darwinian view that many physical and psychological traits of organisms are evolved adaptations. Pan-adaptationism is the strong form of this, deriving from the early 20th century modern synthesis, that all traits are adaptations, a view now shared by only a few biologists.[2] In other words, modern evolutionary thinkers too often apply adaptive explanations to animal behaviour. Much of what evolutionary thinkers attribute to natural selection may occur as a result of other factors. They may be biologically based non-adaptations – by products of evolution (common in physiological traits). Or, in humans, they may be culturally determined.

Answer 91

An anti-predation effect without increased vigilance. Water skaters sit on the surface of ponds and are predated by small fish. Attack rates do not differ with size of group. But, predation is still lower per individual as group size increases. There is just less chance of being one of the unlucky few (Foster & Treherne, 1981).

Answer 92

Most evolutionary theorists apply post-hoc after-the-event explanations of traits; they are said to rarely test a priori predictions. Put another way, they don’t apply the hypothetico-deductive model of hypothesis testing using inductive and deductive logic. However, in defence, it may not always be the case that explanations are post-hoc. e.g., 0.7 WHR and female attractiveness. And...post-hoc theories are not necessarily untrue (e.g., sex differences in spatial abilities may well be due to our hunter-gatherer past).

Answer 93

The idea that behaviour is controlled by genes with little or no contribution from the environment. This may be reflected in the phrase “A gene for…”. Implies a caused relationship between a gene and the behaviour exhibited by the organisms possessing it. Critics of evolutionary theories argue that such explanations emphasise the rigidity of animal behaviour. Does seem to be a natural assumption that a particular trait is caused by genes. Society seems to be obsessed with finding a genetic cause but not a societal one (e.g., depression, criminality). But, is the genetic determinism argument a ‘straw man’? May well be. Nobody really believes that genes determine behaviour. Evolutionary thinkers constantly emphasise the lack of determinism. “The Myth of genetic determinism” (Dawkins, 1982). In the Extended Phenotype, Dawkins criticises the idea that anyone holds a deterministic view (and also defends the selfish gene).

Answer 94

Reducing complexity to a few basic rules or common principles. This of course is a central idea associated with the selfish gene. Complex behaviour has been reduced to the gene. The assumption is that when everything else is constantly varying the common factor will be the gene. So, in an animal’s environment, many many factors change. The one thing that is stable is said to be the gene (as in the oarsman example). Reductionism is fine in the lab [the very act of running an experiment is to reduce a phenomenon to its basic factor/s] but in the real world many factors influence behaviour. And, all animals interact with their environment, i.e., animals are part of the ecology/environment.

Answer 95

Evolutionary explanations of human behaviour are based on two central tenets. 1. Like physical traits, the mind, cognition and behaviour have been shaped by evolution whereby nature has selected those cognitive capacities which have resulted in a reproductive benefit “the human mind evolved under the selection pressures faces by our human ancestors as they lived by hunting and gathering in Pleistocene environments”. (Mithen, 1997) Nature has selected the most efficient psychological traits and behaviour which help to maximise the propagation of one’s (selfish) genes. 2. The mind consists of ‘mental modules’ which evolved to solve specific adaptive problems that our ancestors faced in their environment of evolutionary adaptation (EEA). “the mind consists of a Swiss army knife with a great many, highly specialised blades; in other terms, it is composed of multiple mental modules. Each of these blades/modules has been designed by natural selection to cope with one specific adaptive problem faced by hunter-gatherers during our past….the mind has more than a capacity for ‘general intelligence’ – there are multiple specialized types of intelligence, or ways of thinking”. This ‘modularity’ notion contrasts the opposing view, i.e., that the mind possesses an abstract general purpose learning mechanism.

Answer 96

The original proponent of modularity does not agree with its over application. The criticism of modularity is not just an issue with the human mind….. The search for a ‘kin recognition module’ is a good example of behavioural ecologists assuming that the animal mind is modular. Recall that following the Hamilton revolution, researchers sought evidence that animals are particularly good at recognising kin based on genetic relationship. It is plausible/likely that this ability is based on a general purpose mechanism designed to recognise everything. That is, the visual system.

Answer 97

Optimality models assume optimality when the cost is least and benefit most (i.e., b/c). However, this ratio can be large when there is no real difference between benefits and costs. i.e, very small benefits divided by very small costs can yield very large b/c ratios when in fact there is little real gain to the animal.

Answer 98

Very difficult to falsify theories and hypotheses. If a behaviour is found not to be optimal other explanations are easily at hand: The wrong units of optimising were used; the experiments were not done well enough; the model is wrong.

Answer 99

On human behaviour. On the construction of knowledge, i.e., how culture influences ideas about how behaviour occurs. Recall the argument: males prefer a particular waist-hip ratio because this ratio is associated with peak fertility in females. However, modern culture is obsessed with body shape, particularly those that conform to the 0.7ish ratio. The construction of knowledge Evolutionary explanations of animal behaviour may actually reflect the current (socially constructed) status quo. e.g., theories that ‘predict’ that females should be coy and males should compete for females. This could just as well reflect the status quo, a status quo based on culture/society/attitudes nothing to do with genes and evolution. Another example: Hunter gatherer hypothesis

Answer 100

Here are 3 reasons.. 1)This field of study, in particular ethology, has largely influenced many current fields. (e.g., evolutionary psychology). 2) This field maps onto the classic issue of nature versus nurture. (The early ethologists were associated with the ‘nature’ school of thought). 3) This general area is not just another academic discipline. More important than that!

Answer 101

One robust human memory phenomenon is the serial position effect. Recall of information presented serially is influenced by their serial position and by certain manipulations. The so-called primacy and recency effects can be differentially affected: The type of words presented affects Primacy but not Recency e.g., common words increase the Primacy but have no influence on Recency. The imaginability also affects Primacy but not Recency. Repetition of words also does. Delaying recall does the opposite (i.e., affects Recency but not primacy).

Answer 102

Episodic memory receives and stores information about temporally dated episodes or events, ……and it is always stored in terms of its autobiographical reference to the already existing contents of the episodic store.” (Tulving, 1972). What is the precise nature of recall-recollection-remembering in the DMTS and the serial position paradigms? Can an animal remember seeing a stimulus or is it just familiar? In other words, do animals have episodic-like memory? To examine episodic memory, human memory research often makes the distinction between familiarity and remembering (or recollection; akin to episodic memory). The distinction between familiarity and recollection has been examined in humans with the ‘remember-know’ paradigm. This procedure is a slight variation of a standard recognition memory paradigm (as opposed to free recall). A recognition memory paradigm…….

Answer 103

Thus, are animals in memory experiments ‘remembering’ or ‘knowing’? If they are ‘remembering’ they will therefore have episodic-like memory. What is an appropriate definition of remembering or having episodic memory? Often argued (e.g., Clayton & Dickinson, 1998) that episodic memory is memory for ‘what’ occurred, ‘where’ something occurred, and ‘when’ it occurred. Thus, evidence that an animal possesses what, where, and when information for an event would suggest the animal has episodic-like memory.

Answer 104

The birds simultaneously stored perishable wax moth larvae and non-perishable peanuts for later consumption (in different locations). The birds have a large preference for the larvae and are aware that they perish (after 124 hours). This appears to demonstrate that the birds knew what was stored (larvae or peanuts), where it was stored (in the different locations), and when it was stored (either recently or 124 hours ago). On the basis of this and other similar experiments, Clayton, Dickinson and colleagues have therefore argued that the birds demonstrate episodic-like memory. Hampton and Schwartz (2004) however argue that what where and when memories can take a semantic form rather than episodic. For instance, knowing that we were born and where and when this occurred satisfies the criteria of episodic memory but is clearly semantic. Tulving (2002) also argues that the scrub-jays “may just ‘know’ what kind of food is where, and what state it is in – fresh or rotten – without knowing how or why they know it”

Answer 105

Meta memory is knowing what you know. Hampton (2001) examined whether Rhesus monkeys have metamemory using a DMTS method….. If the monkey decided to take the memory test and selected the correct stimulus it received a desirable reward. If the monkey decided not to take the test it received a less desirable reward. Occasionally, the monkey was required to take the test even though it had declined. Results: The monkeys were more accurate when they chose to take the test compared to when they declined. This suggests that the animals were aware of their own memory. Because they were required to monitor their memory before the test was presented, the monkeys could not have been responding on the basis of familiarity or associative conditioning.

Answer 106

In 1978 Premack & Woodruff published a landmark article What is theory of mind? Attribution of mental states to oneself and others. Most well-known within developmental psychology. The ‘false-belief’, or ‘Sally-Anne’, task...

Answer 107

A chimpanzee was shown short films of human actors faced with different kinds of problems (e.g., trying to reach inaccessible objects). The film was stopped before the actor found the solution and the chimpanzee was offered a choice of 2 photographs. Each photo depicted the actor in the situation shown in the film but only one showing the solution. The animal consistently chose the correct photo. Premack and Woodruff argued that this was because the chimp was attributing a mental state to the actor

Answer 108

Common in ground nesting birds such as the Plover. An attempt is made to draw a predator from a nest. But, does this involve ToM or simple Darwinian selection for injury feigning behaviour? In this article Ristau reports that Plovers are more likely to display if a human approached a nest and looked at it than if they did not look ----------------- Deception in chimps (Woodruff & Premack, 1979). 4 chimps saw food being placed in one of four containers that were out of reach. One of the trainers would then enter the room and always pass the chimp the food if the chimp pointed to the correct location. But, a different trainer, when seeing the chimp point to the food location, would always keep the food for himself. After 120 trials all 4 chimps only pointed to the correct location in the presence of the first ‘cooperative’ trainer; they deceived the second trainer. This suggests that the chimp could attribute a mental state to both trainers - “He keeps the food for himself”. But… Knowing how to deceive and knowing that you are deceiving are very different things. Knowing how to deceive can occur via classical/associative conditioning.

Answer 109

The mirror self-recognition test The paradigm: An animal who has experience with mirrors has a mark (e.g., a red odourless, non irritant spot, placed on its head). The experimenter records the frequency with which the animal touches the spot in the presence or absence of a mirror. Chimps and Orangutans touch their head more with the mirror present. Suggests they know it is themselves in the mirror.

Answer 110

Exists three ways in which an animal can acquire information. Genetically – but the info can be limited and rigid. Learning – enables an animal to adapt to the specific local ecology. Cultural transmission – Kummer (1971) argued that experimenting with the local environment may be dangerous (e.g., food & predators). ‘Tradition’ is a safer way of acquiring information.

Answer 111

Great tits, blue tits and milk bottle tops. In the 1940s these birds began to open milk bottle tops with their beaks. Some argued (e.g., Bonner, 1980) that this was cultural, being due to imitation. Monkeys can imitate washing potatoes. this then spread throughout the colony of monkeys. Showing that they learn from imitation of relatives. But at a very slow rate.

Answer 112

Easy to think that the songs that birds sing are innate. But they do seem to learn them. During the 1930s, 40s and 50s. W. H. Thorpe showed that chaffinches learn their songs from other chaffinches. Birds raised in isolation sang very different songs from normal chaffinches. Thorpe also showed that isolated birds sang songs they heard from tape recordings. Chaffinches also copied precisely songs that they had only heard during the first few weeks of life, yet they did not sing these themselves until able to sing at about 8 months old.

Answer 113

This experiment thus suggests mate copying. What else could be happening? Guppies, like many other animals, prefer to live in groups. (e.g., the dilution effect). Thus, the focal female may go to the end of the tank where the male just was to be in a group. Although the model is removed before the focal female chooses, she may still be employing the rule: “swim to the side of the tank that just a moment ago had 2 fish (as opposed to the side of the tank that had 1 fish). A second experiment attempted to control for this possibility. The experiment was identical to the first with the exception that the 2 male fish were replaced with females. If the ‘be part of a school’ hypothesis is correct the same pattern of results should be observed. The mate copying hypothesis by contrast would not of course predict any copying with all female fish. Results: fish chose randomly. Thus the schooling hypothesis was refuted.

Animal Behaviour Flashcards

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