Chapter 7

Question 1

Research 7.1: Improved Foraging Efficiency in Salamanders

Answer 1

1) Salamanders feed under rocks and logs on a wide variety of invertebrate prey

Question 2

RED BACKED SALAMANDERS & FORAGING EFFICIENCY: Research Question and Hypothesis

Answer 2

Does their foraging efficiency improve with experience? Learning would improve salamander’s skill as predators

Question 3

RED BACKED SALAMANDERS & FORAGING EFFICIENCY: Methods

Answer 3

a) Examined predatory skills of lab-reared two-week-old individuals with no prior foraging experience
b) Standardized hunger levels by doing three feeding trials (separated by 14 days)
c) Presented four termites and recorded capture attempts, successful captures, and the number of prey that escaped after capture

Question 4

RED BACKED SALAMANDERS & FORAGING EFFICIENCY: Results

Answer 4

a) Neonates captured few prey in the first trial
b) Capturing ability improved in the subsequent trials
c) Individuals rapidly learned to forage in a more efficient manner as they gained experience

Question 5

T or F: researchers wondered if learning is always adaptive and a long-standing answer was that evolution should always favor improved learning ability but the answer may be more complex

Answer 5

True

Question 6

What does Learning Theory teach?

Answer 6

a) That two factors affect the evolution of learning: the regularity of the environment and the reliability of past experience
b) As environmental regularity increases, learning will become less favored
c) As reliability of experience increases, learning will be strongly favored since individuals that learn will have higher fitness
d) The real world falls between the two extremes: a dynamic world where reproduction in each habitat can vary or a fixed world where only one habitat leads to high fitness

Question 7

Research 7.1: Fiddler Crab Habituation

Answer 7

a) Habituation: the reduction and then lack of response to a stimulus over time
b) Stimuli can be biotic or abiotic and any reaction to a stimulus is a response
c) Crabs leave the safety of their underground burrows to forage and mate, exposed to predation by avian predators
d) Previous worked showed that crabs habituate to nonthreatening humans but do they habituate to other objects

Question 8

FIDDLER CRAB HABITUATION: Methods

Answer 8

a) Dummy predator was placed in a fixed location
b) The researchers would move the dummy over the crabs for 1m and then returned it to its initial position (runs)
c) Video cameras recorded whether the crabs responded by running toward their burrow and if they went back into them

Question 9

FIDDLER CRAB HABITUATION: Results

Answer 9

a) On the 1st run, almost 100% of crabs ran into their burrows
b) After 14 runs, fewer than 60% of crabs responded, showing a dramatic decline in response behavior, evidence of habituation to the dummy predator
c) Crabs closer to the dummy entered the burrow more frequently than crabs further from the dummy

Question 10

Research 7.2: Neurotransmitters and Learning in Chicks

Answer 10

a) Imprinting: rapid learning that occurs in young animals during a short, sensitive period and has long-lasting effects
b) Greylag geese hatchlings imprinted on Konrad Lorenz’s boots since they were the first object they saw
c) In the brains of domestic chickens, the intermediate and medial parts of the hyperstriatum ventrale (IMHV) play an important role in memory related to imprinting

Question 11

CHICKS & NEUROTRANSMITTER RELEASE: Research Question

Answer 11

Is the release of neurotransmitters from the presynaptic neuron associated with imprinting learning?

Question 12

CHICKS & NEUROTRANSMITTER RELEASE: Methods

Answer 12

a) Half of chicks were trained by exposure to a visual imprinting stimulus while the rest were the control group and had no visual stimulus
b) During imprinting training, birds would attempt to move towards the stimulus with a running wheel recording these measurements
c) They measured the strength of imprinting by placing an imprinted object in front of them and a novel object
d) Killed the chicks, dissected IMHV tissue and conducted assays to measure the release of neurotransmitters

Question 13

CHICKS & NEUROTRANSMITTER RELEASE: Results

Answer 13

a) Found higher glutamate in the IMHV tissue of trained chicks compared to the controls
b) There was no difference in GABA
c) However, among the trained birds, chicks that most strongly imprinted on the test object had higher levels of GABA in their brain
d) Glutamate was more strongly released in the brain of birds that visually imprinted on an object, while GABA was correlated with the strength of imprinting

Question 14

Research 7.2: Dendritic Spines and Learning in Mice

Answer 14

a) Neural Plasticity: structural change in the number of synapses and strength of chemical synapses between neurons
b) Synaptic connections are dynamic due to dendritic spines: small protuberances on a dendrite that typically receive synaptic inputs

Question 15

MICE & DENDRITIC SPINES: Research Question

Answer 15

Does the dynamic nature of dendritic spines play a role in learning?

Question 16

MICE & DENDRITIC SPINES: Methods

Answer 16

a) One group of mice learned a new motor skill: running on a rotating rod suspended above a cage floor
b) Another group received no training and served as controls
c) They used transcranial two-photon microscopy to examined fluorescent-labelled dendritic spines of living subjects

Question 17

MICE & DENDRITIC SPINES: Results

Answer 17

a) Both young and old mice that learned the new motor skills showed significantly higher levels of dendritic spine formation
b) The performance of mice on the rotating rod was associated with the number of new spines formed
c) Over two weeks, most of the new spines disappeared
d) Lifelong memory may be associated with the formation of new spines during learning (more research is required)

Question 18

Research 7.2: Avian Memory of Stored Food

Answer 18

a) Caching food for the future is only useful if the food can be relocated
b) Some rely on local landmarks, like rocks and logs, but most use their memory
c) Corvids and Parids are common species that cache food, with some relying heavily on caching and some not so much
d) If cache recovery is accomplished through memory, species that cache heavily should rely more on a well-developed memory

Question 19

AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Research Question

Answer 19

Does brain structure differ between birds that do and don’t need to remember the location of cached food?

Question 20

AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Hypothesis

Answer 20

Hippocampal formation (HF) size in the brain correlates with spatial memory capability

Question 21

AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Methods

Answer 21

a) Assembled data on HF size for 13 species of corvids and ten species of parids, adjusted for differences in body and brain size
b) Characterized species as: (1) a non-hoarder, (2) a non-specialized hoarder that caches food occasionally, or (3) a specialized hoarder that relies heavily on cached food for survival

Question 22

AVIAN CACHING BEHAVIOUR & HIPPOCAMPAL FORMATION: Results

Answer 22

In both families, specialized food hoarders had larger HF size than species that rely less heavily on cached food, species that do not cache food exhibited the smallest HF

Question 23

Classical Conditioning

Answer 23

a) The ability to learn new associations between a stimulus and an innate, or unlearned response
b) Begins with an innate response to a stimulus, like salivating in response to seeing food
c) Unconditional Stimulus (US) is food and the Unconditional Response is saliva
d) The Conditional Stimulus (CS) is a bell which was rang in association with the food and the Conditional Response (CR) is saliva
e) A dog would salivate after simply hearing the bell, even in the absence of food

Question 24

Research 7.3: Pavlovian Conditioning for Mating Opportunities in Japanese Quail

Answer 24

a) They studied how classical conditioning affects mating behaviour in Japanese quail, medium-sized Asian birds commonly raised in captivity
b)

Question 25

JAPANESE QUAL & MATING OPPORTUNITIES: Research Question

Answer 25

How does learning affect fitness?

Question 26

JAPANESE QUAL & MATING OPPORTUNITIES: Hypothesis

Answer 26

Individuals can benefit by learning to associate environmental cues with mating opportunities

Question 27

JAPANESE QUAL & MATING OPPORTUNITIES: Methods

Answer 27

a) Researchers conditioned adult males and females in the lab to two different mating situations using cages that differed in size, location, and appearance (wire or Plexiglas)
b) Each bird learned that mating always occurred in one cage condition (CS+) and not the other (CS-)
c) For half of the birds, a mate was added after two minutes only when they were in the Plexiglas cage
d) For the other half, a mate was added only when they were in the wire cage
e) No mating was allowed for females during conditioning because they can store sperm, which may bias the results
f) Focal individuals were tested in both cages: researchers presented these individuals with a mate and then counted the number of inseminations that occurred
g) Eggs were collected, incubated, and allowed to develop for one week before being examined for embryos

Question 28

JAPANESE QUAL & MATING OPPORTUNITIES: Results

Answer 28

a) Males fertilized more eggs in the cage where they had been conditioned to expect a mate (CS+)
b) Females also had more eggs fertilized in the (CS+) condition
c) Both sexes achieved greater reproductive success in the condition where they had learned that mating opportunities occur
d) Pavlovian conditioning can affect fitness

Question 29

Research 7.3: Fish Learn Novel Predators

Answer 29

a) How do animals know to avoid predators?
b) Juvenile Lemon Damselfish were studied
c) Larvae develop in open water for about a month and then they settle on the Great Barrier Reef
d) Fish that perceive chemical alarm substances response with innate anti-predator behaviours like reduced feeding, increased vigilance, etc.

Question 30

LEMON DAMSELFISH & PREDATOR LEARNING: Research Question

Answer 30

How do fish learn about predators?

Question 31

LEMON DAMSELFISH & PREDATOR LEARNING: Hypothesis

Answer 31

Damselfish make associations between conspecific chemical alarm cues and the odour of a heterospecific fish to learn their predators

Question 32

LEMON DAMSELFISH & PREDATOR LEARNING: Methods

Answer 32

a) Created a “cocktail” of chemical odours using adults of four fish species caught from the reef: two fish predators and two non-predators
b) They mixed water from each of the species’ separate tanks to form the cocktail of chemical odours
c) They collected damselfish recruits that haven’t been exposed to predators yet
d) Half were conditioned to the cocktail and a conspecific alarm substance, the other half were conditioned to the cocktail and seawater
e) Tested by exposing them either to odours from one of the cocktail species or to the odours of two novel species, only one of which was a predator
f) Recorded the amount of time the fish spent feeding, their distance from their shelter, and time spent inside the shelter

Question 33

LEMON DAMSELFISH & PREDATOR LEARNING: Results

Answer 33

a) When the odour of each species was added, damselfish conditioned with the cocktail of species and alarm substance reduced their feeding time significantly more than did the controls
b) The test fish had apparently learned a new association between the odour of each cocktail fish and predation risk, as indicated by the chemical alarm substance
c) Lemon damselfish can rapidly learn associations between fish odours and the risk from unfamiliar predators and can respond in an appropriate manner by reducing their feeding time
d) They don’t have innate knowledge of predatory species and must learn to identify them as predators

Question 34

Operant Conditioning

Answer 34

a) Involves learning associations between learned behaviours and outcomes
b) Positive Reinforcement: a behaviour becomes more likely due to the presentation of a stimulus, such as food
c) Negative Reinforcement: a behaviour becomes more likely due to the removal of a stimulus, such as pain
d) Positive Punishment: a behaviour becomes less likely due to the presentation of a stimulus
e) Negative Punishment: a behaviour becomes less likely due to the removal of a stimulus

Question 35

Research 7.3: Learning Curves in Macaques

Answer 35

a) Humans have an innate preference for a larger amount of food compared to a smaller amount because food intake affects fitness, so more is usually better
b) They studied the strength of this preference in rhesus macaques

Question 36

MACAQUES & LEARNING CURVES: Research Question

Answer 36

How quickly can individuals learn to overcome an innate preference?

Question 37

MACAQUES & LEARNING CURVES: Methods

Answer 37

a) They offered six subjects a choice between one or four peanut halves that were placed in the experimenter’s open hands
b) If they reached for four, they got one and if they went for one, they got four
c) Twenty trials were conducted each day with a 20-second delay between each of them

Question 38

MACAQUES & LEARNING CURVES: Results

Answer 38

a) Each subject showed a strong initial preference for the hand with four food items
b) They learned to select the hand with one food item in order to receive four but there was tremendous variation in their learning curves
c) One macaque learned quickly, attaining a low error rate after 340 trials but another took over 2700 trials to attain a low error rate

Question 39

Research 7.3: Trial and Error Learning in Bees

Answer 39

a) Can operant learning be studied in more natural settings?
b) Given that individuals differ in learning rate, does learning ability affect fitness?
c) Bumblebees use a variety of cues to learn which flowers provide nectar and pollen food rewards
d) Bees feed on many types of flowers but have an innate preference for the colour blue since blue flowers tend to have more nectar

Question 40

BEES & LEARNING CURVES: Methods

Answer 40

a) Worked with 12 colonies that contained uniquely marked workers
b) All bees were first allowed to feed from artificial flowers that contained sugar water
c) Each flower was multicoloured, both blue and yellow
d) Once bees were used to feeding from artificial flowers, researchers began training trials
e) Bees were placed in a flight arena where half the artificial flowers were all blue and half were all yellow, only yellow had sugar water and blue was empty
f) Bees had to learn that they would be rewarded for probing yellow flowers, instead of their innate preference for blue flowers

Question 41

BEES & LEARNING CURVES: Results

Answer 41

a) They recorded over 100 flower visits pre bee as bees searched for food
b) Bees in all colonies were making mostly incorrect choices due to their innate preference for blue flowers but all eventually learned to select mostly yellow flowers
c) Again, colonies differed in their learning rate, some learned quickly but some more slowly

Question 42

BEES & LEARNING CURVES: Continuation

Answer 42

a) They investigated whether this variation in learning was associated with differences in fitness in a natural environment
b) They allowed bees from each colony to forage on wildflowers and then measured foraging success based on a bee’s weight when departing and it’s weight upon return to the hive, with the difference being the mass of nectar
c) Bees were allowed to forage naturally for six days, providing data from thousands of foraging bouts
d) Colonies differed in food delivery: those quick to learn in the lab delivered more food per hour
e) Conclusion: bees can learn where to feed by trial and error and that learning ability can influence fitness

Question 43

Research 7.4: Learned Anti-predator Behaviours in Prairie Dogs

Answer 43

a) Black-tailed prairie dogs are large social rodents that live in grasslands
b) Their predators include ferrets, coyotes, bobcats, hawks, and rattlesnakes

Question 44

PRAIRIE DOGS & SOCIAL LEARNING: Research Question

Answer 44

How do young prairie dogs learn to avoid predators?

Question 45

PRAIRIE DOGS & SOCIAL LEARNING: Hypothesis

Answer 45

Young prairie dogs learn anti-predator behaviours from adults

Question 46

PRAIRIE DOGS & SOCIAL LEARNING: Methods

Answer 46

a) Captured juveniles with their mothers within two days of emergence from their burrows
b) Each mother and litter were housed in a separate enclosure with an artificial underground burrow at one end
c) Each juvenile first went through an assessment of anti-predator behaviour with predator test stimuli
d) They used a black-footed ferret, a prairie rattlesnake, a moving hawk model, and a cottontail rabbit (non-predator control)
e) They filmed each juvenile for ten minutes to record their anti-predator response
f) Five week training period where they were randomly divided into two groups and exposed to predators
g) One group spent five weeks with an experienced adult that had lived in the wild
h) Another trained alone or with an inexperienced sibling
i) They measured the juveniles’ activity level, frequency of fleeing, anti-predator vocalizations, and vigilance behaviour when alone as a test

Question 47

PRAIRIE DOGS & SOCIAL LEARNING: Results

Answer 47

a) Treatments strongly affected anti-predator behaviour
b) Prairie dog juvenile pups trained with an adult were less active, produced more alarm calls, exhibited more vigilance, and more often fled to the burrow when exposed to a predator
c) They were released back into the wild and after one year of testing, the juveniles reared with an experienced adult had higher survivorship
d) Juveniles learn anti-predator behaviours from experienced adults and that learning helps them survive

Question 48

Research 7.4: Social Information Use in Sticklebacks

Answer 48

a) Local Enhancement: individuals look to other foraging individuals as a cue to the location of food
b) But location is only one aspect of a food patch, more important is the quality of the patch or how much food it contains
c) Public Information: knowledge obtained from others about the quality of a resource

Question 49

STICKLEBACKS & PUBLIC INFORMATION: Research Question

Answer 49

Do animals use public information to assess patch quality?

Question 50

STICKLEBACKS & PUBLIC INFORMATION: Prediction

Answer 50

If only local enhancement is available, individuals will use it, since high numbers of fish should indicate the best patch. However, if a fish can observe the feeding success of others, they should use that public information to select a food patch, regardless of the number of fish

Question 51

STICKLEBACKS & PUBLIC INFORMATION: Methods

Answer 51

a) Divided a tank into three areas
b) Each side compartment had a feeder, creating a “food patch”
c) The centre area contained a compartment with a single observer, the test fish
d) In the FIRST TEST, a test fish could see conspecific “demonstrators” at each food patch - six demonstrators were at one food patch, and two were at the other
e) No food was provided from either feeder so only LOCAL ENHANCEMENT information was available, the number of demonstrating fish
f) After 10 minutes, the barriers were removed and the observer was allowed to swim freely
g) They recorded how much time the test fish spent in each compartment and at the centre near the companion shoal

Question 52

STICKLEBACKS & PUBLIC INFORMATION: Results

Answer 52

a) The test fish spent significantly more time at the patch that had previously contained six demonstrators and near the central compartment than in the compartment with only two demonstrators
b) The Sticklebacks were using the number of fish at each food patch as a cue to the quality of food available

Question 53

STICKLEBACKS & PUBLIC INFORMATION: Continuation

Answer 53

a) They wanted to determine whether Sticklebacks would use public information to estimate patch quality
b) In a SECOND TEST, they manipulated the feeding rates of demonstrators at each patch
c) The test fish would watch demonstrators feed on bloodworms from each patch
d) The patch with two demonstrators were designated the “rich patch” and food was released from the feeder there six times during the ten-minute trial
e) The patch with six fish was designated the “poor patch” and food was released there only twice during the trial so feeding rates differed between them
f) After barriers were removed, the test fish exhibited a strong preference for the rich patch even though only two fish were there
g) Conclusion: Fish do use public information to select a patch. When local enhancement and public information provide contradictory information, fish rely on public information to select a food patch since it more accurately portrays patch quality

Question 54

Research 7.4: Ptarmigan Hens Teach Chicks their Diet

Answer 54

a) The hallmark of teaching is the active participation of an experienced individual in facilitating learning by a naive conspecific
b) Three widely accepted criteria for evidence of teaching are (1) one experienced individual (teacher) modifies it’s behaviour only while in the presence of a naive pupil; (2) the behaviour is costly for the teacher; and (3) the pupil acquires knowledge or a skill more rapidly through the actions of the teacher than it would otherwise
c) Some birds like chickens are precocial, or highly developed and mobile when they hatch, meaning they quickly need to learn what to eat
d) Ptarmigans feed on a variety of plants, their natural habitat contains many dozens of plants but their diet is composed of just a small subset of available plants
e)

Question 55

PRECOCIAL PTARMIGAN CHICKS & SOCIAL LEARNING: Research Question

Answer 55

How do chicks learn the best plants to feed on?

Question 56

PRECOCIAL PTARMIGAN CHICKS & SOCIAL LEARNING: Hypothesis

Answer 56

Chicks can learn to identify important food plants from their mother’s food calls

Question 57

PRECOCIAL PTARMIGAN CHICKS & SOCIAL LEARNING: Methods

Answer 57

a) Chicks naturally follow hens for several weeks after hatching
b) Occasionally, when one or more chicks are nearby, a hen will drop bits of food it’s eating, produce a unique vocalization (food call) and bob its head up and down
c) In response to this food call display, nearby chicks will run to the hen and feed
d) Researchers observed seven marked hens and their chicks in over 100 feeding bouts and noted all food call displays
e) Also recorded the food items eaten by hens and chicks, the food plant associated with each food call display, and the behaviour of chicks in response to the call

Question 58

PRECOCIAL PTARMIGAN CHICKS & SOCIAL LEARNING: Results

Answer 58

a) While hens fed on over a dozen plants, they produced food calls in association with only six
b) Food call displays always resulted in chicks feeding on the plant the hen had been feeding on, and there was a positive correlation between the proportion of food calls associated with those species and the proportion of food in the diet of the chicks
c) The plants consumed by chicks had significantly higher protein content - protein is a limited but important nutrient for growing chicks
d) Also, chicks of hens that produced the greatest number of food calls consumed significantly more protein in their diet than chicks of hens that produced the fewest food calls
e) Clearly, hens were biasing food call production to plants high in protein and chicks learned to consume a diet high in protein

Question 59

Research 7.4: Tandem Running in Ants

Answer 59

a) Teaching also requires evidence that the teacher modifies it’s behaviour when the pupil is not learning
b) Specific ants live in small colonies that often contain fewer than 100 workers
c) Colonies are often located in loose rubble or small rock crevices but when they become unsuitable, colonies often move to more stable, higher-quality locations
d) A small number of scouts search the environment for food or better nest locations
e) When a valuable resource is located, the scout returns to the nest to recruit additional workers, this takes form via a tandem run (two individuals moving together) in which the experienced scout physically leads the naive worker to the resource

Question 60

ANTS & TANDEM RUNNING: Research Question

Answer 60

Is tandem running a form of teaching?

Question 61

ANTS & TANDEM RUNNING: Methods

Answer 61

a) Used 1m arenas with the nest at one end and a food source located at the other
b) They recorded the movements of eight independent tandem runs, including the movement of the first scout to find the food, its behaviour while engaged in tandem running with a recruit, and the movement of the recruit back to the nest

Question 62

ANTS & TANDEM RUNNING: Results

Answer 62

a) Leaders moved toward the food when the follower maintained antennal contact by tapping on the legs and body of the leader
b) Occasionally, the recruit would break away from the leader and engage in a circuitous movement, perhaps acquiring visual information about the environment
c) When physical contact was broken, the leader would slow down or stop moving until the follower was close enough again
d) Slowing down to wait for the recruit meant that tandem runs were costly for the leader, as it took four times longer for the leader to move between the nest and food
e) However, recruits engaged in a tandem run located the food significantly faster than naive scouts, meaning they benefited from the behaviour of the leader
f) Followers would subsequently become leaders for new recruits
g) Tandem running behaviour satisfies all three primary criteria for teaching

Question 63

Behavioural Traditions

Answer 63

a) Differences in behaviour that are transmitted between generations through social learning, among populations
b) EXAMPLE: local song dialects (birds, whales, porpoises, dolphins), song is learned from an adult tutor and so changes can spread rapidly through different populations
c) EXAMPLE: Bottlenose dolphins off the coast of Australia remove marine sponges from the substrate and wear them on their rostrum or beak as they probe the seafloor to locate submerged prey in rough rubble, this is only found in one population of dolphins near Shark Bay
d) They found that this behaviour appears to be transmitted primarily from mothers to offspring, suggesting that social learning plays a role
e) EXAMPLE: Chimpanzee populations vary in their use of stones to crack nuts, their use of twigs to fish for termites, and in specific grooming and courtship behaviours

Question 64

Research 7.5: Foraging Behavioural Traditions in Great Tits

Question 65

GREAT TITS & FORAGING BEHAVIOURAL TRADITIONS: Research Question

Answer 65

Is a novel foraging technique a behavioural tradition?

Question 66

GREAT TITS & FORAGING BEHAVIOURAL TRADITIONS: Methods

Answer 66

a) Conducted in eight subpopulations of birds that use nest boxes for breeding
b) From each population, two males were captured
c) Males from five subpopulations were trained to open a puzzle box to obtain food by sliding a door left or right: the males from two groups were trained to slide left and the other three were trained to slide right
d) The males from the three remaining subpopulations were controls and received no training
e) After four days of training, the birds were returned to their subpopulations and three puzzle boxes were established in the local environment
f) They recorded whether the individual obtained food by sliding the door left or right
g) Data was collected over 20 days and then boxes were removed, 9 months later, the boxes were reestablished in three of the subpopulations and behaviour was recorded again
h) In each subpopulation with trained demonstrators, knowledge about how to obtain food from the puzzle box spread rapidly through the population
i) They grew to use the same one technique
j) Birds in subpopulations learned the solutions used by their populations’ trained demonstrators, an example of behavioural tradition
k) 9 months later, knowledge about how to obtain food from a puzzle box spread rapidly in the two populations that previously had trained demonstrators, and most birds again use the same technique that the original birds demonstrated
l) Behavioural traditions can persist over multiple generations

Question 67

Research 7.6: Tool Use in Capuchin Monkeys

Answer 67

a) Selection can favour tool use when it enhances foraging ability
b) In many cases, individuals learn to use a tool by trial and error after having observed other but some species appear capable of understanding the problem to be solved by the tool and then discover a functional solution without trial and error
c) How Capuchin monkeys selected stones to use as hammers to open nuts
d) Typically, a nut is placed on a log and a stone is dropped on the nut to open it

Question 68

CAPUCHIN MONKEYS & TOOL USE: Research Question

Answer 68

Can capuchins select the correct stones?

Question 69

CAPUCHIN MONKEYS & TOOL USE: Methods

Answer 69

a) Provided eight different individuals with a palm nut at a log and a choice of stones supplied by researchers
b) The first two experiments offered natural stones that differed in type (sandstone or quartzite) or varied in size and weight
c) They recorded the first stone touched, the stone transported to the log and used to hit the nut, and the individual’s success at obtaining food
d) Each individual was tested ten times in each experiment: they selected the heavier quartzite stone 90% of the time
e) In the next three experiments, they offered them novel artificial stones whose weight did not correlate with size (a condition not typical in nature)
f) EXP3: two stones, same size, different weight
g) EXP4: two stones, either light and large or heavy and small
h) EXP5: three stones, light and small or light and large or heavy and large
i) In these experiments, individuals more often tapped, lifted, or rolled the stones prior to selecting one for use which allowed them to gain information about the weight of the stone
j) Showed that they do not simply rely on past experience like trial-and-error learning to select functional tools to obtain food, implying a cognitive ability that suggests an understanding of the relevant feature of a functional tool, its weight.

Question 70

Research 7.6: Insight Learning in Keas

Answer 70

a) Such work on birds often involves a string-pulling task, where food is typically suspended from a string attached to a perch, the food is out of reach so to obtain it, a particular sequence of behaviours is required: reach down from the perch, pull up on the string with the beak, place a foot on the pulled up loop of string, release the string, and repeat until the food is brought within reach
b) Insight learning would suggest that the bird has an instantaneous solution with no further improvement over time

Question 71

KEAS & INSIGHT LEARNING: Methods

Answer 71

a) Presented a string-pulling task to seven hand-raised keas (a large parrot)
b) All were born in captivity and ranged in age from seven months to six years, having no experience with strings
c) On the first day of testing, a familiar toy was attached to the string and baited with food
d) All six adults solved the problem in the first trial and four obtained the food within 15 seconds
e) The juvenile solved the problem on the second trial, needing only 24 seconds

Question 72

KEAS & INSIGHT LEARNING: Results

Answer 72

a) Adult keas can solve a complex problem without trial-and-error learning and provide support for the notion that they have an understanding of cause-and-effect relationships

Question 73

Research 7.6: Numerical Competency in New Zealand Robins

Answer 73

a) Birds were not wary of humans and are very easy to observe up close since their habitat is more remote
b) The birds live in forests and regularly capture large invertebrates that they dismember into smaller pieces to eat
c) These food items are cached in depressions in tree branches for later
d) Birds rely on cached food to survive the winter but their food also may get stolen
e) It’s important for them to assign the caches relative importance: a cache with many food items should be more valuable than one with a single item, this requires numerical competency

Question 74

ROBINS & NUMERICAL COMPETENCY: Research Question

Answer 74

Can species in the wild exhibit numerical competency? Does this require extensive training?

Question 75

ROBINS & NUMERICAL COMPETENCY: Methods

Answer 75

a) Presented mealworms to 14 subjects on a tree branch that contained two cache sites
b) While a subject was observing, the researcher placed a number of mealworms in one cache location and then covered it with leather
c) then they placed a different number of mealworms in the other cache location and covered it with another piece of leather
d) Items were placed slowly so they could see each addition
e) They recorded which cache the robin selected

Question 76

ROBINS & NUMERICAL COMPETENCY: Results

Answer 76

a) The birds preferred the larger cache when the total number of food items was fewer than ten
b) When caches contained more than ten food items, there was no significant difference in cache selection
c) Since caches were covered, they could not visually compare the number of items in each cache, they must have counted
d) These results indicate that wild New Zealand robins have a sophisticated numerical sense when dealing with small numbers

Question 77

Research 7.6: Cognitive Buffer Hypothesis in Birds

Answer 77

a) Why have big brains evolved? One answer is the Cognitive Buffer Hypothesis: large brains, despite their costs, provide survival benefits through flexible behaviours that are learned
b) Large brains increase individuals’ capacity to learn and allow them to survive and reproduce better in an unpredictable, changing environment
c) Research found significant negative relationships between relative brain mass and adult mortality rates, suggesting that big-brained species have lower mortality rates

Question 78

Research 7.6: Brain Size and Cognition in Guppies

Answer 78

a)

Question 79

GUPPIES’ BRAIN SIZE & COGNITIVE ABILITY: Methods

Answer 79

a) Six replicate lab populations from guppies
b) They selected for large brains in three populations and smaller brains in the other three populations
c) They randomly paired single males and females and allowed them to reproduce
d) After females gave birth, the parents were sacrificed to measure their brain and body mass
e) The offspring of parents with the largest and smallest relative brains were used as breeders for the next two generations

Question 80

GUPPIES’ BRAIN SIZE & COGNITIVE ABILITY: Results

Answer 80

a) Relative brain size evolved rapidly in the replication populations over three generations
b) 48 F2 generation individuals were tested for cognitive ability
c) During training trials, white cards with two or four symbols were placed at either end of the aquaria
d) Food was provided only at the end containing the card with four symbols
e) During a test trial, both types of cards were present but no food was provided
f) Each individual was exposed to three training trials followed by a test trial repeatedly until it had completed 48 training trials and eight test trials
g) They compared the number of correct choices (four symbols) for each fish for each of the eight test trials
h) Large-brained females made significantly more correct choices than small-brained females; no difference in males
i) This result supports the cognitive buffer hypothesis: large-brained individuals apparently learned to associate the four black symbols with the presence of food more rapidly than did small-brained females
j) Food is a more important resource for females than males which may explain the difference observed across sexes

Question 81

Research 7.6: Cognitive Performance and Fitness in Bowerbirds

Answer 81

a) Cognitive Performance Hypothesis states that there should be a positive relationship between cognitive performance and fitness

Question 82

BOWERBIRDS & COGNITIVE PERFORMANCE: Methods

Answer 82

a) Placed a red object under a container near the bower
b) Satin bowerbirds have a strong aversion to red objects near their bower and so individuals needed to determine how to remove it from the container
c) They measured how long it took individuals to solve this problem
d) To measure fitness, they video-monitored all males throughout the breeding season to obtain data on the number of copulations for each male

Question 83

BOWERBIRDS & COGNITIVE PERFORMANCE: Results

Answer 83

a) Males with high problem-solving ranks tended to have the highest number of copulations
b) This suggests an association between cognitive performance and fitness for male satin bowerbirds, supporting the cognitive performance hypothesis