2xc3 midterm 2

- Of the estimated 1-10 million insect species, about 10,000 feed on blood and about 100 of those show a preference for human hosts and blood
- The Aedes Aegypt mosquito in Africa spreads yellow fever and dengue to up to 400 million people annually
○ The A.formous subspecies lives in forests and gets their blood from forest species and they are black
The A.ageypti get their blood from humans and are brown (domestic)

- It is hypothesized that one subspecies may like human blood more based on where they laid their eggs, or also based on the odours of blood that attract them
Main question is if genetics were the reason for odour preferences

Don't generally breed in nature as they live far apart however they can produce viable offspring

- Experiment found that blood preference has to do with chemosensory receptors known as odorant receptors
○ Genetic variants of the OR gene in domestic subspecies were sensitive to sulcatone (present in human) than the forest subspecies
§ These variants were also over expressed (produced more functional products)
○ Therefore, foraging preferences relied on sensitivity and expression in OR variants

If we find allele 1 is associated with a variant of behaviour Y, and allele 2 with another variant, we are studying genes from a proximate perspective

- Some workers become aggressive and butt one another
- One of the workers becomes queen after this
- Chemical signalling is hypothesized to be the reason behind termite workers not reproducing
When this signalling ceases, the butting behaviour begins

○ Used RNAi to silence the expression of the Neofem2 gene in queens - this eventually had no effect on their behaviour however in the workers, increased their butting behaviour
○ When a queen failed to produce a pheromone coded for by the silenced gene, workers became aggressive and that caused them to reproduce
Suppression of worker reproduction by the queen was directly related to pheromones associated with the Neofem2 gene

Mendel's first law (Law of Segregation): Individuals have two copies of each gene that such genes remain distinct entities and that these genes segregate during the formation of eggs or sperm

(Law of independent assortment): Whichever allele is passed down to the next generation at one locus is independent of which allele is passed down at another loci

○ Independent males (majority) guard a small mating territory
○ Satellite males do not defend their own territory but they share a territory with an independent male (form an alliance and court at the same time)
○ Satellites are smaller and have lighter plumage
○ These birds are controlled by a gene with two alleles labelled S and s (there is a third strategy but less than 1% use it - called female mimic strategy)
○ S - satellite behaviour and s- independent behaviour

- Polygenic behavioural traits are traits associated with variation at one or more locus
○ Researchers often search for a "set" of genes that overall contribute to the expression of that trait
Looking for quantitative trait loci

By using marker loci

Select two parental strains that are different than one another in terms of quantitative trait and then differ a set of marker alleles
§ Parental strain 1 may have a lower distribution of trait values than strain 2 and strain 1 may be homozygous for ABC marker alleles and strain 2 may be heterozygous for abc alleles

Cross strains to create a progeny (the F gen), if the parents are homozygous at the marker loci the G gen will be heterozygous at each marker locus and will manifest intermediate values

Mate F to create F2 gen and measure their genotypes and value of quantitative trait
§ From this you can infer which marker loci are most closely associated with QTLs for the behavioural trait in question
□ You can see a large difference in the quantitative trait values associated with the AA, Aa and aa stereotypes
Does not mean the A marker locus is influencing the quantitative trait value but it implies that this locus is linked to an important quantitative trait locus

○ Studied fear and anxiety
○ Recorded open field behaviour in mice
○ Chose two genetic lines of mice that were bred under artificial selection
○ High open field and low open field activity in two different lines
○ Fear and anxiety was measured when placed in two different mazes (measured through defecation as high defecation rates and low activity are associated with fear in rodents)
○ Collected DNA from animals' spleens and identified QTLs for fear on 6 chromosomes
○ QTLs for fear displayed in mazes was found only on chromosomes 1, 2 and 15
○ Across 5 behavioural measures, done by Flint and colleagues, evidence of QTLs was found on 14 chromosomes
○ More recent work has found emotionality on 20 chromosomes

- Toma and colleagues exploring foraging behaviours in bees at a certain age
○ Looked at per gene development in fruit flies
○ Examined how levels of per messenger RNA might influence developmental changes associated with being a forager
○ Measured mRNA levels in lab-raised bees and added natural colony of bees
○ Recaptured marked bees at day 7 and day 24 of experiment and measured per mRNA
○ Per mRNA is greater in older bees
§ Can be due to age differences alone or age-related shift to forager
Precocious foragers (those who begin foraging at 7 days old) had the same per mRNA levels as older bees

○ Examined effect of mvl gene on manganese transport in bees and its implications on foraging
§ Manganese affects the way bees respond to sucrose
○ Pollen foragers have a higher response to sucrose than nectar foragers
§ Both have stronger response than nurse bees
Higher manganese in foragers than nurses
Stronger manganese in pollen foragers

- FOXP2 gene in certain brain regions is associated with both song perception in birds and language acquisition in humans
- Experimental works suggests that when the FOXP2 gene is knocked out in young zebra finches and their ability to copy songs as adults is severely impaired
- mRNA levels in the zenk gene of finches increases number of neurons in the neostriatum (area of forebrain associated with song pattern recognition)
- Zebra finches exposed to other birds' songs had a much reduced zenk mRNA response
- No increase in zenk expression either after birds were placed in no song experimental treatment
- If a zebra flinch is exposed to the same conspecific song repeatedly, all of the above responses described return to their baseline levels
○ This habituation occurs when an animal is exposed to the same stimulus over and over

○ Examined interaction between expression of zenk gene and habituation of zebra flinches to familiar song
○ First exposed zebra flinch to song of conspecific and found increase in zenk mRNA
○ Increase in zenk mRNA was also found during habituation to song
Once song becomes familiar, the neural changes were no longer caused

- Entire genome of great tit bird has been sequenced
- Proximate data collections allows us to see which genes play a role in great tit behaviour
- Searched for evidence of natural selection acting on great tit chromosomes
- From an ultimate perspective, what researchers found that many genes linked to cognition were overrepresented in areas of the genome that showed evidence for positive natural selection
Found positive selection on the early-growth response protein gene (EGR1, a gene linked to general memory and learning abilities and one that is critical to song learning in birds)

- Examining within-species differences in prairie voles who display parental care
- Vasopressin is controlled by avpria gene
○ Long version of avpria allele is associated with prosocial behaviours like parental care and affilitave interactions with mates
- Hammock and Young experiment
○ Bred two lines of prarie voles
§ One homozygous for long avpria allele
§ One homozygous for short avpria allele
○ Hypothesized to display different social behaviours because of allele length
Males with long avpria allleles displayed more pup licking and grooming of pups and responded positively to familiar females than shorter-allele males

○ Explored territorialism in house mice, stickleback mice, and honeybees
○ Exposed individuals to either a territorial intruder or a neutral object that served as a control and they sequenced their brain mRNAs
○ Territorial response in all 3 involved a "toolkit" of G-protein coupled receptors
○ Researchers found number of genes linking to synapsis formation, dendrite growth and nerve cell differentiation in the brain that showed similar expression to territorial expression

Cells in in development (except sperms and eggs) are totipotent - meaning they can divide into any cell types

- Regulatory enhancers of genes are a section of DNA that lie outside of that gene but is involved in regulating the timing and level of that gene's expression
○ They don’t code for protein sequences but they control the spatial and temporal expression of nearby genes
○ They act like on and off switches
○ A single gene can have numerous regulatory enhancers and the enhancers can act independently of the others on that gene

- Temperature has strong olfactory senses in insects
- Van Baaren et al..
○ Examined temperature related developmental changes in the parasitoid wasp
§ Usually lay egg in host species and adult females avoid hosts that have already been parasitized
§ Wanted to test if females ability to learn how to find suitable hosts would change when they find themselves ready to lay eggs
§ Raised larvae a 4 deg
§ Control: larvae not exposed to 4 deg atmosphere
§ After, female larvae were raised in more ideal temp of 24 deg
Exposure to cold temperatures had a strong negative effect on speed at which females learned to avoid used hosts

- Rappelling and ballooning behaviour in spiders
- Erigone atra spider uses both with silk threads
- When ballooning, they yse silk threads to sail long distances
- When rappelling, they create a bridge that they can move along for short dispersals
- Their life cycle involves colonizing and breeding in crop fields to which they migrate in the early spring
Mortality risks are higher during fall migration

○ Hypothesized that they'd rappel more during spring migration when territories are abundant and then switch to ballooning which is riskier during cooler fall migration as they have no guarantee of where they'd land
○ During the fall season, the chances of getting a habitat close to others is small enough that it may be worth the costs of having little control where landing will occur
○ Further hypothesized that they'd use temperature as an environmental cue to decide which strategy to employ
○ Found that spiders raised at higher temperatures were more likely to rappel and the ones raised in cooler temperatures are more likely to balloon
○ Climate change could cause them to use the wrong dispersal strategy
Could eventually cause extinction

- Significant variation in prarie vole child-raising
○ 1/3 raised by only mothers
○ 1/3 raised by only fathers
○ 1/3 raised by both
○ 1/3 raised in communal nests (with mom, dad and other older nest mates)

○ Wanted to see amount of care a pup gets when raised by mother alone versus both parents
○ Pups raised by a single mother were left in their nest alone for longer amounts of time compared to both-parent moles
○ Both-parent moles received more grooming and licking
§ When looking at the mother specifically, they experienced the same amount of licking
§ Group differences in licking were due to an absence of a male
○ When pips grew up females with a single mom licked their pups less than females that grew up with both parents
Both males and females from the single mother groups took longer to find a mate

- Younglings in nest are raised by parents and older siblings
Adults and "helper" siblings defend the nest from predators and they remove parasites from nests and developing fry

○ Hypothesized that the presence of parents and helpers may provide younglings with behavioural skills that are beneficial in species that live in social groups
§ By freeing up time to interact with others rather than always having to be on guard for predators
§ By serving as role models for developing offspring
○ They raised newly born fish in groups together
§ In one treatment, there were no adults, and in the other one adult female and one male were present and an adult female helper
○ They were all tested in competition with each other in varying scenarios (like having to defend their territory)
§ Found that fish raised with either adults/adult helpers displayed behaviour less costly in energy but could still defend their territory
Unclear if due to observational learning or simply having more time to interact with each other socially

Data suggests that females remain in their nest to help their mothers raise the next litter of young

○ Wanted to see if experienced females (females that stayed with mom) would be better mothers than those who didn’t
○ Created experienced and inexperienced females by removing or not removing mice from their natal nests
○ IF females were rmeoved from nests at 20 days old and reared in all female group and EF were not removed from their nests and stayed with their mother until she got pregnant again
○ Results showed that they were both good parents and produced more and more litters over time
EF litters had higher rate of survival as EF females exhibit superior nest building behaviour

Male meadow voles have larger territories than females, and outperform them on spatial tasks because they have a larger hippocampus region that contributes to that outperformance

○ Females face more spatial difficulties and have larger hippocampi
○ Females always lay their eggs in the nests of other birds
The need to monitor for other nests, like keeping track of when the other female birds will leave their nest and then remove her eggs

○ Tested cowbirds on a memory task
○ Showed birds 25 open cups and one cup had millet seeds in it
○ Bird was allowed to identify millet cup for 2 mins
○ The bird was removed from the scene and lids were placed on the cups, before bringing the bird back in, all cups had millet placed in them and were shaken to minimize odour cues
○ Some birds returned after one hour and some returned after 24 hrs
○ Males and females spent the same amount of time searching and their motivation levels were equal, however females made fewer mistakes and during both breeding and non breeding season
○ Unlike voles that have a lot of sex-based spatial memory advantage
Overall, female crowbirds have better spatial memory

- 3 big questions
○ How do animals learn?
○ Why do animals learn?
What do animals learn?

A rat that experiences no food for twenty- four hours is more likely to eat than a rat that has just been fed. Most people would say that hunger per se, not any learning by the rat, explains its increased proclivity to forage, even though the experience of not being fed did affect the rat’s behavior when it was presented with food (Shettleworth, 1998)

- Evolutionary ecologists describe a relationship between learning and something called phenotypic plasticity
Phenotypic plasticity is the ability of an offspring to produce diferent phenotypes depending on environmental conditions

When they grow around predators, they develop spines, but when there are no predators, they don’t develop spines

○ Some birds move their wings and tails in a way that flushes out insects from underneath for their consumption
○ The painted redstart increase flapping of wings and tails and forage insects from overhanging branches
The hypothesis is that they learned that they will get food out of this motion, but it could very well simply be a genetic response

○ Found that while it is true that they increase wing and tail flapping in the presence of branches, they also do the same thing in a lab when they are not rewarded for it
○ They put naïve birds under branches and then removed them near the branches and they flapped both times
Example of phenotypic plasticity

- For example, we want to learn about learning in rats
- We can place a blue stick in front of them, and study their response, as rats will notice this disturbance and will turn their heads towards it
- If rats become more likely to turn their head over time, sensitization as occurred
- If rats become less likely to turn their heads over time, habituation has occurred
Habituation can become an issue with ethological experiments because if you were to design an experiment in which you observe the reaction of a prey in presence of a predator (without the predator being able to harm the prey) the prey can become habituated to the predator and then always assume that it won't attack it which may not be true outside of experimental conditions. This can also be the case for animals in captivity that may be released later on

- A rat is given a blue stick paired with the odour of a cat (an odour they fear), 5 secs after the blue stick is in place, the odour is sprayed
- The rat will learn to pair the odour with the blue stick
- The stimuli and responses of the experiment
○ Conditioned stimulus: Blue
○ Unconditioned Stimulus: Cat odour
○ Conditioned response: Rat hiding due to odour
Unconditioned response: Fear

Any stimulus that signifies something positive, like the smell of food or the presence of a mate

Any stimuli that signifies something negative, like the presence of a predator

The presence of one stimulus indicating that another thing WILL happen - produce excitatory conditioning

The presence of one stimulus indicating that another thing WILL NOT happen - producing inhibitory conditioning

Once a CR has been learned by pairing a US and CS1, a new stimulus is presented before the CS1 and then new stimulus ends up eliciting the CR and then the new stimulus becomes a CS2
Rat case: Pairing the blue stick (cs1) with a yellow light (cs2) preceding the appearance of a blue stick, once rat learns to pair the yellow light (US) with the danger associated with the cat odour, second order conditioning has occurred

Pavlovian conditioning affects learnability, which is the ability to learn under certain conditions

Consider 4 groups of rats, suppose group 1 goes through classical conditioning with the CS1 of the stick and the US of the cat odour. Group 2 goes through conditioning with the CS2, the yellow light presented simultaneously with the blue stick. Just before the cat odour is sprayed, both groups are tested in response to the blue stick, if the yellow light is overshadowing the blue stick, rats in group 2 will respond less strongly to the blue stick when it is presented alone than rats in group 1, and the CS2 (yellow light) has made it harder for rats to pair the stick and odour .
- In group 3, rats are first trained to assocate blue stick with cat odour, but then the yellow light is presented at the same time as the blue stick, and then both are presented with the odour, (they have learned to associate blue stick and cat odour before light is added to the procedure). Blocking would occur with this (group 3) of rats respond less strongly to the yellow light when it is presented alone - as if the blue stick and odour pairing blocked their ability to associate the yellow light with the odour
In group 4, the rats are exposed to the blue stick but no cat odour for a long time, but then at some point the blue stick and odour are paired together, if group 1 has difficulty learning than group 1 (where standard pavlovian pairing occurred), they group is exhibiting latent inhibition

- When response made by an animal is reinforced by a reward or termination of aversive stimulus or response made by an animal is discouraged by the presentation of an aversive stimulus or removal of a reward
Different between instrumental conditioning and classical conditioning: Animal must partake in some action or response for conditioning to produce learning

○ Involved testing how quickly cats could escape from puzzle boxes
○ Placed cat in locked box, cats tried many behaviours to get out of box before being successful
○ Cat associated that particular behavior with freedom so was more likely to exhibit that behaviour
Along with Pavlov, he argued that all animals learn fundamentally the same way despite environment

If a response in the presence of a stimulus is followed by a positive event, the association between the response and stimulus will be strengthened, conversely, if the response is followed by an aversive event, the association will be weakened

○ Devised the Skinner box
○ Wanted to create a continuous measure of behaviour that could be divided into meaningful units
○ When a rat pushes down on a lever it is making an operant response because its action changes the environment
Promoted Skinner + Thorndike's views along with Harry Harlow

The ability to learn should be under strong selection pressure, such that individuals that learn appropriate cues that are useful in their particular environment should be strongly favoured by natural selection

- Mid 1960s, Garcia and his team ran a series of experiments that made many researchers in both psychology and biology rethink their approach to the study of learning
- Garcia tried to get rats to form an association between a series of cues
- Bright noisy water treatment had water associated with noise and a light
- Tasty water was paired with a taste
- One of the waters was paired with either radiation, a toxin, an immediate shock or delayed shock
- The radiation and toxins made the rats physically ill, while the shocks were simply painful
- Rats quickly learned to pair tasty water with the radiation and toxins and avoid it but didn't learn to pair bright noisy water with toxinsadiations and avoid

- Garcia and Koelling found that shocks were easily paired with bright noisy water and not tasty water
- Garcia and Koelling said that on the one hand, natural selection would favor the ability
to pair gustatory cues (tasty water) with internal discomfort (getting ill)
○ Mostly discomfort is caused by consumption and not audiovisual cues
○ Peripheral pain would be caused by something not-consumable and can be caused by an audiovisual cue like seeing a predator
- Garcia found that learning in rats can occur without immediate reinforcement
Rats can learn even after delays of 75 minutes when noxious substances were paired with saccharine water

- Fruit flies chose between different locations for laying their eggs, in part 1, the locations had quinine added to it (chemical that flies don't like) and the quinine was paired with either a colour or odour cue
- In part 2, females were exposed to both areas before laying eggs (but had the quinine removed and cues present)
- In treatment 1 colour to be a relaible cue on where to lay an egg but not odour
- In treatment 2, odour was relaible but not colour
- After 40 gens, flies layed eggs in relable spot
○ More individuals learned to pair colour odour in treatment one
Opposite for treatment 2

Animals in groups find foods quicker than solo foragers

- Predicted individuals that live in groips and who must compete with groupmates for resources should learn more quickly than solo foragers
- Studied Zenaida doves - a group population and a solo population
- Got 16 doves from each population, and all had to pull on a metal ring that opened a drawer containing food
- Group living doves did this faster than solo livers
- The tougher the task, the more the difference between these two groups
- One reason could be because of previous foraging experience, and another could be natural selection operating on the ability to learn across the populations
But to accurately test these reasons, they would have to raise lab born individuals and experiment with them

- Used lab-born animals to avoid learned experience with 3 spined sticklebacks
- Some sticklebacks live in areas with many predators, and some live in areas with almost none
- Raised individuals from both groups in a lab, and they both had no interactions with predators
- Trained 8 to associate one side of their home tank with food, they found no differences between groups and found no differences in foraging between groups
- Slowly introduced a predator attack, and found that all fish learned to avoid the side of tank with predator but ones from high-predator populations learned faster
Supports the idea that natural selection has operated on learning and antipredator behavior in these populations

Ethologists, behavioral ecologists and psychologists all suggest hat natural selection should favor the ability to learn over genetic transmission of a fixed trait when the environment an animal lives in changes often but not too often because there is some cost to learning and the ability to learn has some genetic basis

- Subjected flies to learn to associate odour with a shock (5 trials)
- Flies were deprived of food and water and then researchers noted how long it took for thm to die
- Female flies in the learning protocol died quicker (9 hrs quicker) than female flies that had been selected for better learning abilities but not exposed to learning trials or shocked
- Difference assumed to be because of cost of learning, exposure to shock or both
- Evidence of cost of learning was seen when comparing flies in the learning experiment to a control that did not involve learning, but did have the flies experience the shock used in learning trials
Flies in the learning treatment died 4-5 hours sooner than those who had suffered the shock alone

- Found a fecundity cost of learning in the cabbage white butterflies
- Constitutive costs: Paid by good learners regardless of task
- Induced costs: Only paid IF task is learned
- Cabbage white butterflies oviposit on green plants and show an innate preference for green items but there is genetic variation on whether they can be tested to forage for red items
- Females that learned to forage for red items produced fewer and less developed eggs (even when given no learning tasks)
- This learning is likely to be related to investment of brains of individuals seen in individuals in these families
- Constitutive cost was induced cost to learning: butterflies in the families selected for the ability to learn to forage for red items showed a greater decrease in reproductive success
Showed a greater decrease in reproductive success after being part of learning trials involving red items

If environments are constantly changing, there is little to learn from parents, if learned, the learned info could be poitnless

1. Predictability within the lifetime of individual
2. Predictability between the environment of parents and offspring
- Eg) Offspring move to environment very different than parents, here, between gneration environmental predictability is quite low
○ Within lifetime environmental predictability is much higher
Learning is favoured when predictability is high within lifetime of individual

- Used for endangered or threatened species
- Raising them in captivity and then releasing them
- Issue: predation because the species has no experience to predators
Same for translocation

○ One group of hellbender fish were allowed to pair alarm chemical with the scent of brown trout, a predator of hellbenders
○ For a second control groip, the alarm chemical was paired with water
Hellbenders that could pair alarm with predators had a better response to actual predators

- Explored chemical cues in the role of learning in the antipredator behaviour of damselfly
- Damselfly are found in ponds with minnows, and both species are often attacked and eaten by pike
- Fed predators either minnows, damselflies or mealworms
- After 4 days on this diet, a pike was removed fro the tank and damselflies that never had contact with with a pike were exposed to the water from the pike's tank
- When damselflies got the cue that a pike has eaten damselflies, the damselflies reduced foraging, but didn't reduce foraging when they were exposed to the water where the pike ate mealworms
- Further examined the role of antipredator behavior they took all the damselflies exposed to the 3 different treatments and isolated them for 2 days and found that when damselflies were exposed to mealworm eating damselflies, group 1 (damselflies exposed to pike + mealworm and then damselflies) and group 2 (damselflies exposed to pike + minnow and then mealworm water responded with antipredator behaviour by foraging less but group 3 (damselflies exposed to water from pike + mealworms twice)
Displays that learned to associate pike with the scent of any prey with danger so that reduced foraging even with mealworm

- Mongolian gerbils rely on chemical communication to during pairing
- First allowed pairs to form between mates, then presented one group of males with either the scent of mint or lemon and then gave them access to their mates, and then gave other group of males the same odor, but no access to mates
- Males that experienced the pairing of an odor and could access females learned quickly to approach an area where access to females was signalled by an odour while the males in the other group formed no association
- When the same thing was done with female gerbils, they did the same thing and any differences between females and males disappeared over time
- The more equally parental investment is shared, the more similar in temrs of learning the loacation of partners
○ If both parents are putting in the effort to raise offspring, selection pressure for learning ability about partners should be strong in both sexes
If only females are putting in the effort, then they would benefit by being more choosy about the males to mate with

- Parental investment is shared so differences in learning about sex are small
In Japanese quail, where no parental investment is contributed by males, males show greater learning ability in comparison to females

- Breed independently ASAP but many nests fail because of predators
Because of predation, breeders often become helpers at the nests of their close genetic relatives and increase their fitness by helping relatives raise their kin

- Created an experiment with the "churr" call made by tits, to see how they recognize kin
- Got individuals to hear a taped churr of their relative or nonrelative and the tits always preferred the calls of their relatives
- They also ran a cross fostering experiment to see if the birds learn the churr call of their relatives or if it is genetic
○ Chicks raise with biological parents were raised with foster parents
○ Found evidence that call is learned because the calls of the foster siblings raised together were similar as the calls of biological siblings together and the calls of biological siblings were as dissimilar as the calls of the unrelated individuals in nature
The songs of foster parents and foster kids were similar and foster kids' bilogical parents and them had different songs

- Live in colonies in which individuals are constantly interacting with one another
- Reproduction is tightly linked with the dominance a wasp has in its society
Wasps have facial marks that allow for recognition and researchers have examined

○ Tested facial learning in wasps
○ Exposed them to facial images of two other wasps
○ Tested whether they learned to avoid facial image associated with with electric shock and how quickly they learned
○ Wasps could pair face with shock
○ Could only pair shocks with intact faces, not able to understand basic geometric patterns though
○ Hypothesized that facial recognition was selected for to recognize individuals in their colony and if recognition has effects on reproduction, the other wasp species that live a solitary lifestyle and lack specific marking son face, facial recognition may be absent
Tested the other was species Polsites metricus, and no facial recognition was observed

- Picked rats that were selectively bred for 14 years
- Syracuse High Avoidance Rats and Syracuse Low Avoidance rats
- Tested on tendency to avoid auditory and visual cues associated with a foot shock
- Rat was in cage with 2 compartments and could move between them, just before rat was shocked in one compartment, a light and tone were set off
- Rat underwent 10 trials and then went through a 60 second avoidance trial to see how fast it would move to the other compartment when the sound and light were presented
- In each gen, the best SHA were bred and the poorest SLA were bred
- SHA avoided shocks in 40/60 trials and SLA avoided in none
- SLA rats had more anxiety

○ Ran rats through 10 training sessions and then through 60 avoidance trials
○ 70% or more trials - SHA rats showed avoidance
○ SLA rats showed avoidance in less than 10%
○ Some genes were expressed in greater quantities in SLA rats
Hypothesized that avoidance is probably controlled by genes

- Glucocorticoids such as corticosterone are hormones that play a large role in the sress response and learning of many animals
They can affect emotional and cognitive abilities

○ Exposed groups of rats to tests designed to examine the fear response one test involved measuring how rats respond to large open fields or spaces lacking cover because rats fear large open spaces (so fear both tests)
○ Measured amount of time rat stayed frozen and amount of time rat defecated
○ Some rats were placed in one fear test and some were placed in both
○ Rats exposed to both conditions were consistent in that they were relatively anxious
○ Rats are consistent with their response to open environments and ran 140 rats through one fear test and classified them as high anxiety or low anxiety
○ Then rats were tested on spatial learning skills
§ Placed them in water maze and looked at how fast they could find an escape platform to rest on
§ High anxiety individuals took longer than low anxiety individuals to learn to do so
§ High anxiety rats had fewer melanocorticoid receptors so less cortocosterone binded and led to increase in stress hormone ciruclation
§ Could be that rats with few melanocorticoid receptors and many circulating hormones became anxious in the open environment tests or the environent caused a change in availability of melanocorticoid receports and they decreases resuling in more stress hormones and poor performance in water maze

Dust mites are about 200 microns, on the hair parts of the body, pillows and they feed on dead skin

100 trillion (10^11) and about 10% is E.coli

1000 to 100000 per cm^2

Staphyloccocus are typically harmless residents on skin and mucous membranes
Rhinovirus is the common cold

1mm = 10^-3 m
1 micron = 10^-3 mm
1 nm = 10^-3 um
With the naked eye we can down to 0.1 mm (100 um)
bacteria and cells: 1-30 um
Viruses : 20-100 nm

The ability to acquire to require a neuronal representation of new info, an animal may use that infor to determien subsequent behaviour

The ability of organisms and cells to move up or down chemical gradients (performed by sperm and neurons) (sperms are about 50 nm)

-High [] in vagina so they move up to the uterus and then the fallopian tubes
- They use thermotaxis (moving due to temp change) in the fallopian tubes and go from a colder area to a hotter area

Decades of research on simple behaviour (chemotaxis)in bacteria have contirbuted to applied research on reducing human inferitlity

- Hearing
○ You can locate where a sound is coming from by detecting difference in sound arrival time
- Decision making
Seeing

- Sucessive comparison, which requires a minimum of one step memory
- Bacteria can only keep same direction or tumble randomly to change direction
Simulatenous comparison is impossible because the chemical gradient across the body is too small

- Detection by receptors
- Condiction by messenger
- Processing based on messenger concentration (polling)
- Transmission of decision
- Response
Nucleus combines info and sends it to flagella

- No
- There is no true representation of new info and learning requires the representation of new info
This is more like a set of decisions affected by new info

Shared the 2002 nobel prize in physiology or medicine for his pioneering work on c.elegans

- A small soil worm (1mm) that feeds on bacteria with -959 cells and 302 neurons with all synapses mapped and entirely sequenced genome
- Researchers can turn off individual neurons by laser ablation from inidvidual neurons

Copying successful mechanisms of animal behavuour into new gadget
Used knowledge of C elegans to create robot that relies on chemotaxis

Something like reflexes, knee jerks and blins

Similar terms: Instinct, fixed action pattern, motor program
- A behavioural pattern that appears in fully functional form the first time it performed
- Like flies don't need to learn how to court females with singing, it is innate
-

Advantages of innate behaviour
- Rapid response to stimulus
Proper response to the first time the stimulus in encountered, no need for trial and error
- Like birds don't need to learn what material to use to build a nest or where to find it or when and how to build it

- Male chooses a forced branch and weaves around himself
- Then he stands out of the circel until completing the roof and nest cup
- Weaves backwards to create doorway
- After obtaining a mate, he weaves an entrance tube
- Some research done by Lauren Guilette at U of Alberta has found that with Zebra finch, there is some learning involved in nest building

- The insinct has been effective in recovering eggs rolled from nest
- There was no natural sleection egg discrimination in geese

- If the object is smooth and near nest, it must be an egg
- Would also try and hatch a billiard ball (doesn't have to be white and egg shaped)
- Would also work with red cube
- Energy directed toward raising young children
Takes into account that a real egg would never be left out if it rolled out of the nest

- Can damselfly larvae show antipredatory behaviour to an unknown predator and would they benefit from such an ability?
- Use damselflies never before
exposed to pike (predatory fish). That is,
the damselflies have evolved in a habitat
with no pike and are inexperienced with
pike in the laboratory.
Let 3 groups of pikes feed on minnows
(small fish), damselflies (of the same
species) or mealworms (beetle larvae)
• (Note: minnows co-occur in nature with the
damselflies but beetles do not)
• Move the pikes to different tanks with fresh
water and keep them there for 3 days
lace damselflies in tanks containing
the pike water (chemical stimuli of pike
and dead prey)
• (Reminder: many animals rely on smell
much more than humans)
• Measure antipredatory behaviour of the
damselflies
3 treatments involve the smell of pike + dead minnows, damseflies or mealworms

- Mean change in frequency by damselflies
exposed to chemical stimuli from pike fed either
mealworms ( ), minnows ( ) or damselflies ( )
- Strong antipredatory behaviour for pike + dead minnows and pike + dead damselflies

The damselflies showed antipredatory
behaviour (reduced foraging activity)
when exposed to the smell of:
• pike + dead minnows,
• pike + dead damselflies,
• but not pike + mealworms

- They innately avoid these smells
They possess innate antipredator responses to the smell of an unknown fish that has preyed on damselflies or minnows

Question: Can damselfly larvae learn to
associate an unknown predator with danger?
• Would they benefit from such ability?
• Protocol: Use the 3 groups of damselflies
from experiment 1
• Place all the damselflies in tanks containing
the water from pikes fed on mealworms
- Experienced

- Evolutionarily never encountered dead mealworms so there is no innate response
No innate response to unknown fish that has preyed on unknown prey

All damselflies from
Exp 1 were exposed
to chemical stimuli
from pike fed
mealworms
Mean change in frequency by damselflies
exposed in experiment 1 to chemical stimuli from
pike fed either mealworms ( ), minnows ( ) or
damselflies ( ).

Damselflies that were exposed in experiment
1 to chemical stimuli of pike, which was fed on
either minnows or damselflies, showed
antipredatory behaviour to pike + mealworm
stimuli  they learned!
• In contrast, damselflies that were exposed in
experiment 1 to chemical stimuli of pike, which
was fed on mealworms, did not show
antipredatory behaviour to pike + mealworm
stimuli  they did not learn!

Many are innate
• Many others are learned
• Many are partially innate, partially
learned
• Both innate behaviour and learning
abilities are evolved trait

• A newly born baby has
an innate tendency to
feed on his mother’s milk
• The newborn quickly
learns to identify his
mother’s smell &
appearance

1973 Nobel Laureate in
Physiology or Medicine
“for their discoveries concerning
organization and elicitation of
individual and social behaviour”

- Black back gouge
○ Is a migrant unlike herring gulls
○ Chicks are in contact with parents through sound
○ Within an hour the wet chick is dry and fluffy
○ Parent gulls feed their chicks when their chick pecks the parents
§ Innate response from chicks
Parents eat the food that the chicks didn't eat

Red pencil with 3 dots stimulates more responses

Begging chicks tend to peck at a
contrasting dot on an elongated subject =
innate behaviour
• With experience, the chicks learn to
recognize their parents based on vision
and sound

Of the 2 major mechanisms that can change
behaviour over time:
• Evolution is a major biological process
• Learning is an animal trait that has evolved
by natural selection
 Learning abilities are products of evolutio
There is typically heritable variation in
learning ability.
• Therefore, lower or higher learning
abilities, and specific learning abilities
can evolve

Evolution = change between
generations measured at the population
level
• Individual learning = change within
individuals measured on the same
individuals before and after some
experience
Individuals cannot evolve
• Populations evolve through changes in
gene frequencies over generations
• Individual learning is not transmitted to
the next generation
• (Social learning can be transmitted
across generations through offspring
learning from parents etc.

Assuming that individuals show heritable
variation in learning ability:
• Evolution of higher learning ability by
natural selection would require that
individuals with higher learning scores
would have higher fitness
• To evolve higher learning ability through
artificial selection, all we need is to
breed only the individuals with the
highest learning scores

The fruit fly (Drosophila) has been one of the
most important animal models in biology
• Its original advantages were a short
generation time and large, highly visible
chromosomes
• Nowadays, enormous amount of data,
techniques and mutants make it the animal
model of choice in many lab

Flies received 2 food types, made of orange-
juice gel or pineapple-juice gel (agar)
• One food type also had quinine – a very
bitter, harmless substance
3 Components of artificial selection on Fruit flies
- Training (period 1)
- Test (period 3)
Selective breeding (end of period 3)

- Even numbered generation
- 150 flies , aged 14 days from egg
- 1stL hours 0-3
Sweet pineapple and bitter orange

- 2nd period: 3-6 hours
weet orange and pineapple
Flies should have learned that pineapple was sweet

3 period: 6-9 hours
Eggs bred near pineapple because they should ideally remember that the orange was bitter

- odd numbered generations
- 150 flies
- Aged 14 days from egg
- Switched, now bitter pineapple and sweet orange

- Second 2nd period: hours 3-6

3rd period: hours 6-9
- Eggs bred next to orange

- Succeeded at selection of flies with better learning ability
Flies that could successfully learn not to eat the food with the quinine in it

- There is heritable variation in learning in flies there is heritable variation is fly learning
- Smilar heritable variation in learning ability exists in humans
- Learning abilities of wild fruit flies are quite moderate
Natural selection does not favour good learning in flies

Learning abilities of wild fruit flies are
only moderate
•  Natural selection does not favour
good learning ability in flies

Same genes exist in animals and other humans
- STM memory is short
- ITM is intermediate
LTM is long term memory

- Apparatus generates small electric shock
They learn how to avoid it in the dakr

We know the genetic and neurobiological
pathways leading from learning to long
term memory in flies
• Long term memory depends on CREB=
Cyclic AMP-Responsive Element Binding
protein

Goal: improve memory in flies & other
animals including humans
• Create flies with over-expression of
CREBA
• Compare their learning ability to control,
wild-type flies
- CrebA is overexpression of CREB

Creb enhanced flies learn well

Treat mice with a drug that increases
CREBA activity
• Compare their learning ability to control,
wild-type mice

Other companies also closed –
drug development is VERY
expensive

- Work started 60 years ago
The sea slug, Aplysia, has a simple
nervous system and a gill withdrawal
reflex that Kandel’s group has used to
study learning and memory

Flies received training sessions each
consisting of one odor temporally paired
with shock, & another odor presented
with no shock
• The spaced group received 10
sessions separated by 15 min breaks
• The massed group received 48
sessions with no break (the same total
training duration)

Human subjects could memorize the
same material either:
• Eight times successively on one day, or
• Two distinct times a day on four days
• After training, each group received 3
tests on days 0 (immediately following
training), 1 and 7

Students read text and then were
assigned into one of 4 treatments:
1. No test
2. Multiple choice test
3. Multiple choice test with feedback after
each question
4. Multiple choice test with feedback after
the whole test
• Final short-answer test a week later
- Worst to best results as stated above

Stimulants such as amphetamine &
methylphenidate (e.g. Adderall & Ritalin)
are widely used for nonmedical reasons
by:
– students to help study & finish papers &
projects
– faculty & other professionals to enhance
productivit
No drug has been found to enhance
cognition!
• No study has assessed long term effects
of drugs that people take in the (false)
hope of enhancing cognition

Bumblebees feed on
nectar and pollen from
flowers
• Therefore, it is adaptive for
bumblebees to have an
innate tendency to fly to
flowers for food
A typical bumblebee
habitat contains
hundreds of plant
species with flowers
in a variety of smells,
colours and shapes
Different flower species have different
amounts of nectar & pollen
• Plants (in nature) typically bloom for
only a few weeks
• Different areas have different plant
specie
In other words, there is variation among
flower species and in time and space
Conclusion:
• An inexperienced bumblebee cannot know
which flower is the best one in its area
• For example, an innate tendency to visit
little pink flowers would be non-adaptive if
no such flowers bloom in the vicinity of the
inexperienced bumblebee
Bumblebees and flowers
• Solution: the bumblebee samples
different species and learns which one
is the best flower in that bumblebee’s
specific time and place

When there is strong association over
many generations between a cue and
an environmental feature
• For example, flowers = foo

When there is no persistent association
over many generations between a cue
and an environmental feature, but there
is such association over some portion of
an individual’s life
• For example, flower color does not
indicate relative quality, but, after
sampling, a bumblebee can know that
the blue flowers are best now

No. Although learning is beneficial, it
also has costs: time, cost of errors, cost
of brain tissue, maintenance costs,
opportunity cost (learning vs.
reproduction

Animals are more likely to attend to
and learn valuable information

- Any information that increasing fitness

How do animals know what is valuable?
- Social learning
- Innate behaviour and biases
- Evolved emotions (pleasure, fear, sadness, happiness, love)
Repetitions of relevant info

- Females mate at the beginning of winter
- Females leave eggs with males and they place them on their feet
Males do not feed for 4 months until females return
- Females mate at the beginning of winter
- Females leave eggs with males and they place them on their feet
Males do not feed for 4 months until females return

- If chicks get out of nest then baby can fall to death
Use cues to identify chicks
Recognize own nest spot but neither
eggs nor sedentary chicks

Wide variation among birds in learning
to recognize parents and chicks
• Different bird species learn distinct
information, which is most valuable in
their specific ecological settings

Rats were trained to drink from a tube of
water sweetened with saccharin.
• They heard a buzzer each time they
licked
• = “noisy, tasty water”

One third of the rats experienced foot
pain (electric shock) while drinking
• One third of the rats were made ill
(injection of lithium chloride) after
drinking
• One third of the rats received sham
injection (of saline water) as a contro

. Rats’ choice between plain and
sweetened water
2. Rats’ choice between drinking plain
water during quiet and buzzer periods

Poisoned rats avoided “tasty water`

Foot pain rats avoided "noisy water"

Prediction: the sex that relies more
heavily on spatial memory would have
better spatial memory

Compare males and females of two
closely related vole species
The male has a few mates
(=polygamous). The male’s territory
encompasses all his mates’ territories.
• Prediction: The male will be a better
navigator than the female
The male has a single mate
(=monogamous) with whom he shares
the same territory
• Prediction: There will not be a
navigational difference between the
sexes
• (M-polygamous)
• (P-monogamous

- The polygamous species: females made more mistakes than males
In monogamous species: male and female error rate was about the same

Prediction: the brain region that
processes spatial memory would be
larger in the sex with better spatial
memory
- The hippocampus looks like a seahourse

Place cells in the hippocampus provide
through their activity patterns an
organised map of space
• Discovered by John O’Keefe, 2014 co-
winner of the Nobel Prize in physiology
or medicin

- Men with larger ranges may have fathered more children
Women that stayed closer to home successfully raised more children
Predictions are based off of men travelling further than women, and women show greater harm avoiidnace

Men's psychology reflects fitness benefits of takng riisks
- Women's psychology reflects fitness cost of harm

Archeology: femurs and
tibias from men show higher
remodelling, indicating higher
mechanical loads, suggesting
greater range size
• Sexual dimorphism related to
distinct sex roles
Men travel more than women
- In hadza tribes and tisimane, men tavel more for forraging, and Twe of Namibia's Women were more vary of new spaces and men travelled around more and their men travelled more

- Women were much slower than men at virtual navigation task
Argued that if men play more virtual games, they may be better than women
Women made more errors in navigation
Women perform better in this sense except for vocabulary
Regardless of whether they live in city or not,
Men performed better

In humans, the testes start producing
hormones at week 7 of gestation
• Higher testosterone concentrations in
male than female fetuses
Some brain regions have testosterone
receptors
• In fetuses of non-human mammals,
testosterone acts through neural
receptors to influence neuron survival,
anatomical connectivity and
neurochemical specification, producing
sex differences in brain structure and
function
Higher androgen prenatal environment
in girls  better spatial memory

A structural MRI study of London taxi
drivers vs. controls
• Average of two years training before “the
knowledge” test: 25,000 streets plus
locations of interest within a radius of 9.6
km from Charing Cross train station
• Average of 14 years experience as taxi
drive

- Sham operated is control


Men have better spatial memory than women

A structural MRI study of London taxi
drivers vs. controls
• Average of two years training before “the
knowledge” test: 25,000 streets plus
locations of interest within a radius of 9.6
km from Charing Cross train station
• Average of 14 years experience as taxi
driver

They have a larger posterior hippocampus and surprisingly had a smaller anterior hippocampus
- Explanations
○ People with larger hippocampi are more likely to engage in professions that require extensive use of spatial memory
Extensive use of spatial memory modifies hippocampus style

- Pairs of ants run towards new food source in tandem run formation
Ants signal each other about direction and speed

- Marked pairs of ants with coloured dots
○ One coloured dot meant that that ant knew the location of food and the other did not
- The ant that knew the location of the food led the tandem run and the ant that was unaware of the food location followed
- Leaders only continued run if they were tapped on the legs
- Taps cost the leaders because without ants following and tapping them, they were able to get food 4x faster
- Interrupted tandem runs or in instances in which the leader had to wait for followers, the leaders still waited for them
Not a cost for the follower ants because they got to food faster than when foraging alone and returned to nest faster

Defined as the transfer of information from individual to individual through social learning or teaching both within and between generations of animals

- Imo washed the sweet potatoes that the ethologists threw at the beach
- No other macaque did this other than Imo and it allowed her to remove all the sand before she ate the potatoes
- Imo's relatives and peers learned to do this through social learning (process of learning by watching others) and started to wash the potatoes as well
- When researchers introduced wheat to the macaques, it created a novel problem because the wheat and sand mixed together
- Imo put the sandy wheat into water and when the sand sank to the bottom of water, the wheat could be eaten
This was also learned by her relatives and peers but it took a bit longer to learn since macaques find it hard to let of food one they have acquired it

- Observed individuals playing with stones after eating
- First observed with a 3 year old macaque named Glance -6476
- Glance-6476 would bring rocks from the forest, stack them up and then knock them down
- She was also very protective of her stones and would hide them when other macaques came
- Huffman came to study the troop four years later hand stone playing/handling became pretty common from older to younger generations
However nobody older than Glance's generation picked up stone play, but generations younger did

- Examined stone play in a captive troop
- Uncovered age specific differences in adults and juveniles that engage in stone play
- When juveniles play, they play in short bouts with vigorous body actions
○ Consistent with motor training hypothesis that stone play may facilitate the development of perceptual and cognitive skills
- Adults engage in fewer but longer bouts of stone play which may help slow down the deterioration of cognitive processes seen in aging primates
This type of behaviour hasn't been seen in macaques that are not captive, it seems like it is in populations that have more leisure time (freed up bc food is provided for them)

- Young chimps learn behaviours such as watting flies and opening nuts with stones from adults
- However, opening nuts with stones is seen in two populations out of six and is absent in the remaining four
A behaviour such as this one can only be learned if an individual from a population happens to encounter the behaviour

The following definition is used by evolutional and behavioural biologists: Cultural transmission is a system of information transfer than affects an individual's phenotype by means of either teaching or some form of social learning

- If Imo the macaque was not a troop, her potato washing behaviour would have died with her
- Cultural transmission works must faster than natural selection and can cause us to see changes in just a few generations, whereas natural selection may take a few or several generations
Cultural transmission can even have a huge impact in a single generation

- Cultural transmission mostly involves a demonstrator "model" or tutor and an observer
- However there are some situations in which there is interaction required between an observer and learner but there is no social learning or teaching
In these cases (local enhancement and social facilitation) - the observer is drawn to an area by a model or action of the model or is simply amongst models but does not learn a particular behaviour so cultural transmission isn't occurring

- Local enhancement was coined by William Thorpe
- Term is used to describe a situation in which individuals learn from others just because the model happened to be in a particular location (not really through observation)
Once the observer is drawn to the area, they may learn on their own via individual learning

- They feed in groups ranging from 2-1000 individuals
- Local enhancement facilitates foraging
Some are drawn to a foraging area, while some are there just because other birds are there

Mere presence of a model can impact behaviour, whereas in local enhancement, the action of the model is what impacts behaviour

- Examined what factors impact a capuchin monkey's probability of eating a new food
- Treatment 1
○ Control condition
○ A lone monkey was tested on whether it would eat dyed veggies
- Treatment 2
○ A monkey and novel food were on one side of the cage and on the other side there was a group of capuchins without food
- Treatment 3
○ Similar to treatment 2 except familiar food was placed on side of cage with the group
- When comparing treatments, they found evidence of local enhancement but not social facilitation
- Local enhancement evidence was found in treatment 3, because the lone capuchin began to eat the food in comparison to treatment 1
No evidence for social facilitation

The acquisition of a topographically novel response through observation of a demonstrator making that response
- There must be some new behaviour learned from others
- The behaviour must be a new spatial (topographic) manipulation and must lead to the achievement of some goal
○ Like Imo's potato washing

- When humans try to cultivate crops in an area that is not meant for vegetation, it can cause issues with the wildlife that is present there
- 1/3 male elephants in the Aboseli National Park have been dispersed from their natal groups due to the raiding of crop fields
- Many male elephants are killed when farmers raid crop fields
- Elephants live in communities in which individual and social learning both play a role
Patrick Chiyo and Colleagues

○ Wanted to see if male elephants could learn how to raid crops and be vigilant for farmers through social learning
○ Predicted that males associated with others that raided crops with raid crops at a higher rate than those who are not associated
○ Also predicted this effect would be stronger with older elephants
○ As predicted, males associated with crop-raiding males also raided crops faster and this was also true when its second closest associate was a crop raider but not if a more distant was a crop raider
Also predicted for older elephants

○ Tit birds opened the wax board tops of milk bottles that were delivered to Brits' houses in Swaythling
○ Tit birds often open the bottles in seconds and even follow milkmen while they are making deliveries
Found that these tits rarely move 10-15 miles from their natural habitat

○ Some bird may have stumbled upon another bird engaging in this behaviour and picked it up which explains wide distribution
Evidence to support this: birds preferred the same coloured foil prominent in their area - suggesting they imitated each other as foil preference varied across populations

- People are given simple tasks
- Areas such as the dorsal and ventral premotor cortex, inferior frontal gyrus and other areas are constantly active
Our brains respond more strongly to imitating an action done by another human than the same action being done by a robot

- There are mirror neurons in the F5 areas of the premotor areas of the monkey and they become active when a monkey observes something like grabbing food from a tray and then it repeats the action
- Connection to imitation: an action must be fired for the neurons to fire
- Neurons won't fire when an object is sitting there, but they will if that object is being manipulated by a hand
Some evidence suggests that humans also have similar neurons in our equivalent of an F5 area

- Observer repeats what a model does and is typically rewarded
- Extrinsic rewards: Like money
- Intrinsic reward: Feeling proud of yourself
- Differs from imitation in the sense that what is copied doesn’t have to novel and does not need to involve learning and can even occur if the observer knows what the model is doing and
- Does not need to involve new spatial orientation
Animals may pick a mate to copy or resort to someone if their first mate isn't available

- Single male mate put into chambers
- Observer was placed in clear canister in middle of central aquarium
- One male put into each chamber
- Removable glass partitions created left or right sections of the aquarium into which the model female was placed
- Model was placed near male in left or right to rule out male attractiveness and to ensure the model and observer independently chose the mate
- Fish were given 10 mins during which observer female could watch the model near one of two males
- Then observer fish could choose whichever mate she wanted
17/20 times, the observer fish chose the mate chosen by model

- Guppies live in social groups so it is possible that the observer female was choosing the area that had recently contained the larger number of fish
- In the control experiment, females were placed in the end chambers, and the observer female chose the females in the end chamber closes to the model only 10/20 trials
Tendency to school doesn't explain first experiment

- Mice exposed to stable flies do not show any immediate behavioural response to the flies
IF an individual is bitten by a fly, it shows a response by burying itself under something

- NDMA receptor plays role in neural plasticity
- Blocked NDMA receptor of observer mouse
Found observer did not learn to bury itself under debris with blocked NDMA recpeotr

A behaviour that emerges and becomes common within a group of individuals as a result of social interaction

- Used 9 groups of Meerkats
- Created arbitrary landmarks (2)- plastic objects differing in colour and pattern placed near food or water source
- In 7/9 groups, a demonstrator was trained by the researcher to show a preference for 1 land mark
- Saw rise and fall of tradition
- Meerkats followed demonstrator and both landmarks were equally profited but one was preferred by other group members but one was preferred by other group membered (emegred in the 7 non control groups)
Preference lasted for a few days but then disappeared, but then when they learned that either landmark is equally good they had no preference and spent an equal time at both and the tradition died

- Seeded great tit populations where individuals were trained to solve a complex foraging task - opening a sliding open a door that has access to mealworms behind it
- Puzzle box was built so food could be accessed by a brid by either sliding blue door left to right or red door from right to left
- Birds were trained for both ways
- Examined whether door opening tradition spread through populations
- Found that over 400 birds learned this in the deonstrators' populations
- Social network analysis found that birds associated with the demonstrators learned the trait more quickly than birds who were not associated with the demonstrators and continued to prefer the way their demonstrator showed them
Continues for two generations even after removal of puzzle box for a 9 month period

- According to Caro and Hauser, a behaviour can be labeled as teaching if the teacher is providing an immediate benefit to the student but not themselves and students must be naïve to what they are being taught
- The tits opening the milk foil would not be teaching because the tits that opened the foil caps did so regardless of whether there was an observer present
Cheetahs teaching their young how to interact with prey would be teaching (allowing cubs to overtake them and capture prey while hunting)

- At 1 month old, pups follow forager groups and older helpers help them with finding food
- The helpers will incapacitate scorpions and remove their stringers and present it as food to the pups
As pups got older, they were presented with live scorpions

- When played the call of older pups, the foragers brought back live scorpions
- When played call of younger pups, the foragers brought back dead or incapacitated scorpions
Helpers also monitored pups with their food, retrieved more food if pups lost food, modified food If lost by pups (like remover stinger) and also nudged pups that were reluctant to eat scorpions

- Coaching: teacher altering behaviour of student by encouragement or punishment
Opportunity teaching: Actively placing student in a situation in which they can learn

- Fairy wrens teach their unborn offspring a vocal password
- Horsfield bronze cuckoos can parasitize a fairy wren's nest by laying its eggs in it
Fairy wrens teach their eggs a vocal password that chicks mimic when they have hatched, and they repeat in back to the mother to access food

- Hypothesis: Fairy wrens teach their eggs a vocal password that chicks mimic when they have hatched, and they repeat in back to the mother to access food
- More the mother repeated the vocal password, the more accurately the chicks repeated it to access food once they were born
- Call is not innate - it is learned which was found by the cross fostering experiment in which eggs transferred to another nest learned the call of the mother of that nest
- Mothers start to emit password at 10 days of incubation
Cuckoo eggs hatch at 12 days and poorly mimic the call, whereas the fairy wren eggs hatch in 15 days so they have an additonal 3 days of learning

- Found that fairy wrens teaching their chicks comes with a cost
- Vocal passwords attract predators
- In natural nests, predator was higher when females produced more calls per hour
- Nests with high incubation calls pet hour (30/hr) suffered 8x the predation
Even nests with 15/hr suffered 5x the predation in comparison to nests with no calls

- Takes place through teaching or social learning
Finches learning the songs of their father or females developing song preferences based on what their father sang

- "Beaching" or "Beach hunting" - which involves a dolphin surging out water onto a beach to catch a fish and then return quickly and is an overall rare behaviour
- In a study with bottlenose dolphin, only 4 adult females and their calves were observed beaching with consistency
- Another form of beaching: 1-6 dolphins isolate a school of fish and herd the fish toward the land and then create a wave to send them onto the land then surging out of the water to capture the stranded fish
Janet Mann found that only calves born to beachers displays the foraging technique and learn the technique

- Female bottlenose breaks up a marine sponge and places it over her mouth and probes the sea floor for fish prey
Almost exclusively a female trait and young females learn from other and others use tis behaviour associate with each other

- Transfer of info across generations but from older adults and not parents
Common in systems with no parental care

Lab raised monkeys did not react the same way to snakes

- Had juvenile rhesus monkeys not afraid of snakes, and got them to observe older monkeys that were afraid of snakes and their actions around snakes - the juveniles themselves adopted these actions
Made no difference if they observed any adults or their parent
- However if the demonstrators were trained to display fear in front of a neutral object like a flower, the young rehsus monkeys won't copy them
- Suggests there is a predisposition to fear of snakes
Furthermore, when they saw one group of demonstrators not react fearfully to snakes, and another react fearfully, they displayed less fearful behaviour than those exposed to only fearful demonstrators - they were culturally immunized

- Transmission among peers - same aged individuals and occurs in all ages
- Laland and Williams trained same aged guppies to learn different paths to a food source - one with a long path and one with a short path
- Once groups learned the paths, the researchers removed one guppy and replaced it with a new one so each group had most of the experienced ones and 1 new naïve guppy
- Wanted to see if new fish at the end of the experiment would take the route taken by original group members or not
- Found that the guppies followed path that original group members were trained to (horizontal transmission)
Maladaptive: made it hard for guppies to learn other path if they had observed a particular path

- Cultural transmission shapes birdsong but it interacts with genetics of reproductive isolation
- Hybrids of medium ground finch and the cactus finch suffer from lower reproductive success
- No costs for hybridization
- Usually cultural transmission stops interbreeding
- Males learn the songs they sing, and transmit the songs culturally - fathers and sons tend to have similar songs which is genetic because songs are similar amongst paternal grandfather, father and the son
- Females decrease probability of mating with genetic relatives (because they don't want someone who sings like their father)
If male species sings the song of the other, cross breeding can occur which removes cultural transmission pattern

- Guppies from paria river prefer to mate with orange males which is heritable colour
- In one treatment, males were matches for orange body colour with a difference of less than 4%
- In treatments 2-4, the guppy males differed in total orange body colour by 12, 24 and 40 percent respectively
- Experiment: Demonstrator female would be shown with a mal with less orange body colour, meaning the cultural transmission is opposite to the genetic predisposition
- In treatment 1, females copied the mate choice, and in treatments 2 and the same thing occurred
- Cultural transmission overrode a female's genetic predisposition
In treatment 4, females preferred the more orange of the two guppies (genetics overrode cultural transmission) - preference seems to be affected by some threshold

- Found that across a 100 species of nonhuman primates, there was a positive correlation between brain size and innovation + tool frequency
- Innovations are defined as novel solutions to environmental or social problems
- Executive brain volume measures neocortex and striatium sections of the brain
All have positive correlation with social learning, tool and innovation

- Daniel Sol and his team wanted to examine the relationship between brain size and innovation and whether it affected birds when they moved to new environments through introduction programs
Found that birds with high brain sizeody ratios were more likely to survive and thrive

The formation of a new neuronal
representation linking either a stimulus
and a state (classical conditioning) or an
action and its consequences
(instrumental conditioning

Sensitization – increased response to
stimuli following the presentation of a
prominent stimulus (e.g. loud sound,
strong smell)
• Habituation - decreased response to a
stimulus following the repeated
presentation of that stimulus (e.g. loud
sound, strong smell)

- Pre touch: Low response to touch
- Post touch: High response to touch
In control (desensitized): Low pre and post touch
- uses siphon to expel waste
- When it was touched, there was siphon withdrawal
Assumption of a predator being around

- Opposite happens during habitations
During the shadow period, responses to stimuli remained low until shock was introduced again

Many times they involve associations
with context and one’s memory
• Still, they have been useful for
mechanistic research on learning

- Sensitization
○ Watching a scary movie, you would be sensitized to sound and touch
○ Repeated air puffs to the eye would result in blinking and in response to a loud sound
- Habituation
○ Clothing - you don't consciously pay attention to the feeling of your clothes on your skin
○ Anxiety about finals in first vs fourth year

Cs: tone led to US(air puff) led to UR(eye blink) and then CS led to Cr of eye blink
- Eye blinks increased as trials went on
- Extincition caused decline in eye blinking response

Not all changes in behaviour result from
associative learning.
• Examples: limping after leg injury; your
running speed in high school vs. now...
• Fatigue, habituation, sensitization..

- CS and US needs to be paired consistenly
- Randomness and low predictability will mot cause any lorning or association
The best controls
 Same proportions of CS with US and
CS with no US
 Same number of disassociated CS
and US presentations

- How do we know this?
Rat example: They are more likely to associate food poisoning with a novel taste and foot pain with a shock

Associative learning occurs only when
presentation of the CS is associated
with increased probability of the US
• But learning also depends on the nature
of the CS-US pairs
Why?
• Animals have innate predispositions for
associating certain stimuli (CS) with certain
states (US)
• Animals consider both their prior knowledge
and current experience to infer what
relationships are likely to occur
• Posterior knowledge = some function
of prior knowledge & new evidence

P(H1)E= ((PEH1)(PH1))/ P(EH1)(PH1) + (PEH2)(PH2)
- Ideally we want the P(E\H1) to be 1
Tests can also be false positive or false negative
P(H1 |E) - Posterior probability for H1 given Evidence
P(H1) - Prior probability for H1 before any event
P(H2) - Prior probability for H2 before any event
P(E|H1) – Prob. for evidence given that H1 is true
P(E|H2) – Prob. for evidence given that H2 is true

The prior probability of novel food being
the cause of illness is much higher than
that of noise, so animals are innately
tuned to the possible association
between taste and food-poisoning.

There is strong evidence that the animal
brain employs Bayesian-like computations
• Examples:
• Male fruit flies choosing whom to court
• Learning by human infants
• Visual perception in humans

Animals, including humans, encounter
variation in space and time, and
uncertainty
• Animals have evolved means for
making decisions considering these two
fundamental environmental properties

Variation: school and course quality,
Canadian and world cities, friends,
potential mates, mood...
• Uncertainty: State of COVID-19 in fall
2021; the weather next weekend,
summer employment, the source of next
year’s tuition & living expenses, sea
level in 30 years

Variation: Food, predation risk,
competitors..., mates
• Uncertainty: Food to last the night /
winter, surviving to the next breeding
season, winning the next fight for food /
safe feeding location / females, mating
(♂), successful reproduction (♀)

Variation: Learning / sampling,
accepting variation & being prepared to
deal with it
• Uncertainty: body fat (in humans ~15-
30% body weight  ~15 kg = 135,000
Cal  2 months with no food), caution,
alertness, learning, sharing (food,
defence etc.), forecast (air pressure),
insurance (humans),

deltaVt=a(lambda - Vt)
When a CS and US are paired, the
change in the strength of their
association, ΔVt, changes proportionally
to the learning rate, α, the difference
between the maximum strength
possible, λ (lambda), and the current
strength, Vt

The Rescorla-Wagner equation can be
rewritten in its discrete form as:
• Vt +1 = Vt + ΔVt = αλ + (1 - α)Vt
• We can plot either equations:

Max strength, λ=100
• Learning rate, α=0.2
• Initial strength, V0=0
• V1 = 0.2·100 + 0.8·0)=20
• V2 = 0.2·100 + 0.8·20)=36
• V3 = 0.2·100 + 0.8·36)=48.8
• ....
• Vn = 0.2·100 + 0.8·100)=100

nexperienced rats were exposed to a puff of
novel perfume followed by shaking of their
cage, to which rats typically respond by
‘freezing’.
• Suppose the rats can achieve a maximum
associative learning score of 1 and that their
learning rate is 0.5.
• What would be their expected learning score
after 2 trials?


Should get 0.75

They reflect laboratory protocols & are
hard to relate to natural behaviour
• They do not relate to animal evolutionary
biology
• They ignore cognition (defined as
information processing by the brain)

- What is the ultimate reason that dogs learned to salivate when they saw food?
○ Saliva has an enzyme that breaks down food - so being physiologically prepared can help you digest food faster
- Is it a universal phenomenon?
- Do animals learn to associate cues with events and adjust physiologically in anticipation of these events?
Is it adaptive?

Stimulus - main and emerson
Relevant state - near accident
Learned response - fear and caution
Innate response - fear

What we call “drugs” (& many of our
spices) are mostly secondary plant
compounds that have evolved to deter
organisms from feeding on plant parts
• Alcohol is a byproduct of anaerobic
yeast (& bacterial) metabolism
• Animals may possess counter
adaptations for breaking down certain
drugs

Subjects drinking an unfamiliar alcoholic
drink (green peppermint) will show
stronger intoxication than subjects
drinking a familiar drink (favourite beer)
Test
• Tracking a rapidly moving circle with a
mouse
• Word search in a 16 x 16 grid of
jumbled letters
• Subjective intoxication
Stronger effects of alcohol
with the unfamiliar drink
Subjects performed better on average with a familiar drink

Subjects associate familiar cues with
anticipated negative effects and take
(unconscious) physiological measures
to counteract such effects
•  Learning helps animals to anticipate
and prepare the body for events with
strong physiological impacts

Modern cognitive science and evolutionary
research rarely refer to traditional animal
learning
• The experimental techniques are highly
useful and the vocabulary is universally
known by biologists, psychologists &
neurobiologists studying learning &
cognition

Individuals do not learn from others
• Social learning is important where it
occurs
• Because humans rely heavily on social
learning, there has been wide interest in
studying social learning in other species

Males emerge in late July and females
~ a week later
Males defend territories &
attempt to mate with newly
emerged, virgin females
• Both sexes feed on nectar
• Adult lifespan ~2-4 week
Females provision nest with bumblebees

Both sexes show individual learning
• Each individual is on its own – there is
neither social interactions (just male
fighting) nor social learning
• This is typical to most animals
• (There may be social learning that we
do not know about)

The behaviour was first
observed in England in the
1920’s and spread rapidly
among blue tits
• Some kind of social
interactions was probably
involved because of the rapid
spread...
The behaviour was first
observed in England in the
1920’s and spread rapidly
among blue tits
• Some kind of social
interactions was probably
involved because of the rapid
spread...

Weakness – they are not controlled
experiments, (but inspire such experiments

Information: anything that reduces uncertainty
• Private information - inaccessible to others
• Non-private information results in social
information
• Cues reflect inadvertent social information (ISI)
• Signals consist of intentionally communicated
information

Example: in rats, observers rely on
demonstrator breath (=cue) when
choosing novel food (Ch. 1)

s it really different from individual
learning? The outcome is:
1. Social learning can be much faster &
safer than individual learning because
one can avoid much of the trial and
error that accompanies individual
learning

2. Social learning across generations
prevents the loss of information upon an
individual’s death.
• 3. A rare individual's insight can spread
rapidly within populations and across
generations

Local enhancement & social facilitation:
Observers are more likely to visit a
place frequented by others, or to
perform a behaviour performed by
others

Benefit: most often, an
observer joins a model
who is probably at a
location rich in food and
safe

Application in conservation: attract
endangered birds to a restored or
protected habitat

- One seed is hidden under each scale
- Black rats moved into planted pine forests in Israel and feed on pinecone seeds
- The rats chew off the cone and carry it to a feeding place
- the most efficient way to remove
seeds is to start from the base of the
cone and remove the scales in a spiral
upward fashion

Only 3% of adult rats inexperienced with
pinecones learned to use the spiral method
in the presence of experienced rats
• All adult rats reared by parents using the
spiral method used that technique
70% of rats learned the spiral method in
the presence of cones partially striped
in the proper fashion
•  No evidence for imitation

Rat pups are exposed to partially
open cones while feeding with their
mother
Cat mothers provide
“processed” prey to
kittens
• The mothers
gradually increase
the difficulty of the
kitten’s task

Hunting speed of 320 km/h
• Successful parents must hunt several
times a day
• The adaptive value of play – learning
complex skills
• Parents provide learning opportunities =
“simple” social learning (neither imitation
nor teaching

Peregrine falcons, once common in
Ontario, disappeared in the 1960’s
because of DDT poisoning
• Massive breeding effort re-established
the species, which has adapted to life in
the cities, including downtown Hamilton
(Sheraton Hotel)

No evidence for true imitation in the
previous examples
• Do species other than humans imitate

Anthropomorphism – the
attribution of human traits
to non-human animals

Most early reports on imitation in non-
human species were incorrect
An observer learns a new behaviour
by watching a demonstrator
• (Neither the presence of a
demonstrator nor some outcome of
the behaviour are sufficient (e.g.
odour, open cones, wounded prey)

The majority of animals just do not do it
• We can easily do it
• How does the observer’s motor system
‘know’ which muscle activation will lead
to the observed model’s movement?
• Mirror neurons in the pre-motor cortex
are active both when an observer
observes & executes an action
Critical data indicating that an observer
learns a new behaviour by watching a
demonstrator exist for very few species
• Local enhancement is prevalent &
almost certainly explains milk bottle
opening in blue tits

Critical data indicating that an observer
learns a new behaviour by watching a
demonstrator exist for very few species
• Local enhancement is prevalent &
almost certainly explains milk bottle
opening in blue tits

5 observers watched the screen move
to the left in the presence of a (non-
pushing) demonstrator who then had
access to food
• 5 observers watched the screen move
to the right in the presence of a (non-
pushing) demonstrator who then had
access to food

Focals that see demonstrators moving
the screen would move the screen in
the same direction as the demonstrators
• Focals that see the screen move would
either not move it or move it at either
direction

More sceen pushes for matches in imitation than non matched
More screen pushes for non matches in control than matches
- However we don't know if quails imitate in the wild despite this well controlled experiment

There are very few critical experimental
studies indicating (non-vocal) imitation
• (Vocal imitation is well known in a few
orders)
• There are many reported cases of
imitation, which require critical tests
based on the accepted criteria
An observer learns a new behaviour
by watching a demonstrator
• (Neither the presence of a
demonstrator nor some outcome of
the behaviour are sufficient (e.g.
odour, open cones, wounded prey,
open milk bottle)

Task: open a Plexiglas box to get fruit
• Demonstration: half the subjects
observed a demonstrator poking 2
plastic rods & then lifting the lid
• The other half observed the
demonstrator twisting clockwise and
pulling the plastic rods & then lifting the
lid

o control for non-imitative alternatives
– local enhancement – the observers
play with the box because the
demonstrator does so
• Prediction: observers would employ the
technique they have observed to open
the box

A ‘teacher’ modifies its behaviour only
in the presence of a naive ‘student’
2. At some initial cost to the teacher, to set
an example that
3. Would benefit the ‘student

andem leaders knew the location of food
but tandem followers were naive
• Tandem leader kept moving only if tapped
on her legs or abdomen (gaster) by the
follower

Teaching only in the presence of a naive
student.
• Cost to teachers: tandem leaders move 4
times slower when they teach: median of 1.8
vs. 8.4 mm/sec
• Benefit to students: tandem followers found
food faster than when searching alone:
average of 201 vs. 310 sec.

culture – a suite of local traditions that
uniquely identifies a certain population
• Tradition - a distinctive behavioural
pattern shared by two or more
individuals in a social unit, which
persists over time and that new
practitioners acquire in part through
social learning

Chimps approach
termite mounds with
proper tools:
• The first stick is thick
to break into a tunnel
• The second stick is
thin, with a “brush tip”
to extract termites
• The set is unique to
that group
- Each of the 8 chimp communities has its own socially learned traditions

- Suppose that two prey items are available to a foraging bat, does the bat fly in a way to capture the first of these items or does it take into account a path that will get to both of these foods?
Found that bats tended to fly along paths that took into account how to obtain both items and not the first targeted item - this paid off as the bats that only flew to capture one of the preys often failed to catch the second prey item

When an animal encounters a prey type more and more, thee representation of it becomes better so they find it more successfully
- Argued on whether it is a representation of the key features of the prey or the entire prey

- Collection of mathematical models
Employ optimization theory to predict foraging aspects within given constraints

- A forager has to choose between two types
One prey is encountered every 3 mins (encounter time), it takes 2 mins to kill and ingest (handling time) and it provides the forager 300 calories - if this is the prey that leads to the most profitability, it will always be taken by the forager

- Energy intake can be measured
- Foragers can't handle one prey and search for another
- Prey are recognized instantly and accurately
- Prey are encountered sequentially
- Natural selection favours foragers that maximize rate of energy intake
Predicts a critical rate - if a prey type's profitability is higher than this rate it will almost always be taken

- Birds placed in front of moving conveyor belt and put two different mealworms on the belt
- They controlled the rate at which these two prey types were encountered by the birds and the energy provided by both prey types as well as the handling time associated with each meal worm
- Encounter rate of the most profitable prey mattered more than not profitable prey
Can also be used in humans - Kim Hill studied foraging in the Ache tribe in Paraguay and found that their choices matched prey choice model

- A forager should stay in a patch until the marginal food intake (food intake associated with the next food in in its patch) is = to that of across all patches available
- The greater the time in between patches, the longer a forager should stay in a pacth
A forager should remain longer in patches if quality in the environment is poor vs rich, to make up for the travel cost associated with a move from a patch, a forager has to stay longer in a poor patch than a good patch to obtain a fixed amount of energy

- Built artificial trees in aviary with many branches with sawdust filled plotting baskets and under them were mealworms
- Calculated intake at the patches and could manipulate the time taken between patches because each patch had a lid that was either easy to remove or hard to remove
- The optimal time a bird spent in a patch matched the optimal time predicted by the marginal value theorem
Approach can also be used to figure out how long a male should search for a mate

- A linear utility function where every additional food item is valued equally
- A convex utility function where every additional food item has less value - what you can expect a fairly satisfied forager to have (Like value of a scoop of ice cream after consume a cake)
A concave utility function where every additional item is worth more and more to a limit as might be the case for a hungry forager

- Fairly satiated foragers have a convex utility function and are predicted to be risk averse and should prefer to forage in patches with low variance
- Very hungry foragers with concave utility function should be risk prone and prefer high variance patches
- Foragers with a linear utility function should be indifferent to foraging related variance
Rule of thumb: When very hungry, use patches of food where variance in food intake is high

- Presented birds with two trays containing bird seed and once a bird made the choice to go to one tray, the other was removed
- Both trays had the same amount of food but one had a fixed amount of food while the other had a mean value (sometimes less or more)
- Convex utility birds picked fixed trays and birds with concave functions selected variable
Ants grow food through symbiotic relationships with fungi as fungi helps them kill parasites that grow in their fungal gardens

- All 20 species of fungus growing ants had the Streptomyces bacteria
- They transmit it across generations
- Only females posses it during reproduction
- Bacteria produces antibiotics that only wipes out certain parasitic diseases, so parasites that are not a threat to the fungal garden aren't affected
Ants also pick up parasitic spores and place them in their body pockets called intrabuccal pockets and in the pockets is where a chemical kills the spores and then the dead spores are deposited in a discard pile

- Predicted because fungal gardens break down plant matter that becomes available to ants, lead cutter ants might have lost some genes associated with nutrient acquisition
Evidence was found for this during genome sequencing

- Feed on small aquatic insects that live in dense vegetation and need to flush them our from substrate and being in a group can increase ow much is being flushed out
- Mittlebach manipulated group sizes and looked at how manipulating group size of bluegills and placed 400 small amphipods in large aquarium of bluegill sunfish and measured foraging success in pairs and groups
- Positive relationship between foraging group size and individual foraging size success upt oa group size of 4 fish
Increased feeding rate due to more prey being flushed in larger group size and because prey clumped together so when one group member found the amphipods the others swam to the area too

- In Tai chimps, hunting success had a positive correlation with group size in a nonadditive fashion and adding more hunters to a group did not increase the amount of food by a fixed amount for reach new hunter added
- Each new hunter allowed for more food and subtle social rules exist to regular access to fresh kills and assure hunters with greater foraging success than those who decided not to hunt
- No correlation was found between group size and hunting in Gombe chimps and behavioural rules limited a nonhunter's access to prey were absent and they received as much food as the hunters
Success rate for Gombe solo hunters is higher than Tai chimps

Info based on the actions of others as a cue for environmental changes
○ Reduces environmental uncertainty
- Public information models preduct that social foragers in poor patches should leave such patches earlier than solitary individuals because social foragers can use the failed foraging attempts of their groupmates as additional information about when they themselves should leave a patch of food

- Fed in artificial feeder that had 30 cups that were either empty or had only a bit of food
- Given bird fed from feeder alone or paired with another bird, before being paired though, birds had been given the chance to sample a few cups or sample all the cups
When tested on completely empty feeding patches, B1 birds left such patches earlier than B2 (paired bird

- Hippocampal region in birds is known to be associated with food retrieval and corvids are ideal for examining the relationship between hippocampal volume and food storage in more detail because of variation
- Some corvids store no food while others rely on food they have stored over the course of nine months
- Studied jackdaws and Alpine choughs that rarely ever catch food
- Studied four species that do catch food - rooks, European crows, European magpies and Asian red billed blue magpies
- In european jays, food location must be rememered for 6000 to 11,000 seeds for nine months
Greater the food storage behaviour, greater the hippocampal value

Natural selection should favour better caching and retrieval abilities when individuals live in harsh foraging environments where caching and retrieval is at a premium and selection should favour larger hippocampal areas and more hippocampal neurons under such conditions

• From colorado: more food
• From alaska: poor amount of food
• Captured birds from alaska and brought them to Colaroado and then to a lab
• Tested them on ability to retrieve seeds, and birds from alaska captured greater number of seeds ad found greater proportion and made les serrors
• Alaskan birds had larger hippocampus
Caching experiencing does not impact hippocampal size, displayed when both birds were given the same opportunities

- Most likely ancestral trait of corvids is moderate caching
Highly specialized caching evolved twice independently and at least two lineages completely lost ability to cache seeds maybe bc the beneifts did not make up for metabolic cost of maintaining a big hippocampus

- Forager bees learn to pair colour, odour, shape and flower topography with sugar
Birth weight of honeybees can be 80-150 mg and is affected by amount of care given by nurse bees and amount of food present

- Scheiner's experiment
- Tested how quickly they respond to sugary liquid and when bees turned 3 weeks old tested them in pairing citral with sugar
- Found positive relation between birth weight and foraging related learning at age three
- Here was significant variation in learning abilities even emong individuals
- Bees that responded by extending proboscic quickly were the best learners

Lefebve and colleagues on relatinship between foraging and forebrain size in North America and British Isle groups
- Foraging innovation: Ingestion of new food type or use of new foraging technique
- Found that birds with larger forebrains were more likely to have incidences of foraging innovation
- Examined potential fitness benefits associated with being alarge brained bird
- One big untested hypothesis for fitness advantage associated with large brains would be beneficial when a population was introduced into novel or altered environments while innovation might be important