Topics 5 & 6- Development and Learning

Behavioral Development

Often involves both genetics and environment

Genes set limits, Environment affects final phenotype (epigenesis)

What is epigenesis?

In behavioral development when genes set limits and environment affects final phenotype

Examples of epigenesis

IUP and Maternal care

Waddington’s canals

Analogy:

In a shallow groove: only a slight tilt (environmental change) can make the “marble” (trait) go to the other tract (traits you can change like handedness)

In a deep groove: it’s too deep in to go the other way (traits like eye color, heart structure)

Epigenetics definition

Changes in gene expression which are inherited and not caused by changes in DNA sequences

Epigenetics examples

Methylation tags

Men who smoke as young boys more likely to have obese grandsons

Mice with obesity and diabetes genes who are fed healthy diets in pregnancy produce completely healthy offspring

Female water flea experiences predation, offspring born with “helmets”

-if no predation offspring born WITHOUT helmets

Highly nurtured rats become calm adults, neglected rats become anxious

Evolution benefits of neglected rats becoming anxious

Since environment growing up was harsh, they grow up prepared to deal with challenges

Neglected rat pups enter estrus earlier

Why do neglected rats and humans enter estrus/have sex younger?

Growing up in hostile environment = life short reproduce ASAP

Fetal environment and placental morphology

Anytime placenta not fully in shape and functioning, fetus is stressed and produces cortisone gene

Fetus makes organs and they end up having problems- diabetes, obesity, heart disease, insulin resistance, high blood pressure etc

Sex determination mammals

X and Y

2M female mice produce male based litters; 2F females produce female based litters

High ranking females produce more male offspring

Sex determination Birds

WZ females

ZZ males

Drosophila

Ratio of X chromosomes to autosomes

Ants bees sex determination

unfertilized eggs = males

fertilized eggs = females

Environment and sex determination

in reptiles, incubation temps determine sex (Warmer=male)

Some fish change sex after adulthood (remove dom male on reef, largest female converts to male)

Developmental homeostasis Theory

Development seen as a buffering or homeostatic process

Traits have a background of genetic influence

Developmental homeostasis seen in

1) Constancy with which individuals of a species pass through certain stages

-embryology

2) Development of normal physiological and behavioral traits even when placed in abnormal environments

-rural Guatemalan vs American infants adolescent intellectual development

Findings and implications from Guatemala vs American infants

At first, cognitive differences huge but around 10-11 years old they became exactly the same

Means that only a bare minimum of experience is necessary to promote normal development

Deprivation experiments

Harry Harlow and his wife

#1: total isolation for 3,6, or 12 months- aggressive, bad immune system, abused offspring

#2: alone in cage, but near other monkeys- behavior still the same as in total isolation

#3: total isolation w/ inanimate surrogate- prefer cloth to wire, even when wire has milk, become attached to surrogate, better but still inappropriate behavior

#4: total isolation, but allowed 15 mins a day w/ another isolate- they hugged each other, then began to play, became normal adults

-also interacting w/ dogs, reared alone w/ mother, vs only w/ peers

-more normal development w/ peers

Conclusions of Harlow deprivation experiments

Maternal care, physical contact, living in a group impact later reproductive, mating, paternal, social behaviors

Sensitive period = birth to 6 months

Disproved Skinner saying infants only loved mother for nourishment

Postnatal stress and dwarfism

When child extremely stressed, stop growing

Seen in roundworms too!

Need physical touch to reduce stress hormones

3 patterns of development

Restricted

Semi restricted

Flexible

restricted development

highly influenced by genetic makeup, learning has little impact

complete neutral template, all wiring present at birth

ex: cowbird song

-when raised with another species and dont hear their own song, they still know how to sing

semi restricted development

genetic + env

partial template

critical periods when experience shapes behavior = restricted periods

ex: chaffinch song

Flexible development

Mostly learning

open template

ex: zebra finch- can learn any bird song

Critical period

Lorenz borrowed from embryology

Fairly extended

Gradual in onset and termination

Differ between species, individuals, functional systems

Depend on nature and intensity of env stimuli before and during

Only rare conditions alter behavior based on critical periods

Timing of critical periods

Most species early in life

learn from parents and physical env

Imprinting

learning to make a specific response to only one type of animal or object

early in life usually between parents and offspring

filial and sexual- both types occur in all imprinting species

Filial imprinting

development of social attachment to thing or animal

important for socialization, predator avoidance

Critical vs sensitive

critical (time which response is greatest)

sensitive (time which response is possible) imprinting

Sexual imprinting

Species isolating mechanism

Requires longer contact than filial

Important for choice of partner later in life

Acquisition phase and consolidation phase

ex: jackdoll courtship

Japanese quail imprinting

choose to spend time w/ cousins rather than unrelated or siblings

combo of sexual imprinting and habituation (reducing responsiveness to familar individuals)

Imprinting nature and nurture

instinct

but won’t follow unless theres something to follow (env)

Gottleib- duckling vocal cords

-no preference for duck call bc they couldn”t hear themselves

Curlew imprinting

restricted development, completely developed neural template for their parent

why: large flocks w/ other bird species

Chicken and duck imprinting

semi restricted

partial template for identifying maternal call of their species

no visual template

why: vocalization can occur even when vision blocked (ie tall grass)

turkeys and geese

flexible development, no vocalization or visual preference, social bond formed w/ 1st moving object

why: nests apart from other species

Imprinting-like processes in mammals

Olfactory

maternal attachment 5 mins after birth or won’t happen

Elephant and seal vocalization

Shrews from 8-10 days old imprint on odor of mom while nursing

-if nursed by foster mom imprints on her and will not follow real mom

Human incest taboo

Arthur Wolf

data from women in China

-sim puahs vs met arranged human on wedding day

marriage to early childhood bethrothed 3x more likely to end in divorce, produce no children, have more adultery if girls adopted at age 3 or younger

0-3 is when incest avoidance formed

Social play

interacting w/ others in same specie

Wrestling, chasing etc

social skills grooming sexual behavior

communication w/ others

Exercise/physical play

alone

develop muscles, coordination, strength

important for predator avoidance

Exploration play

Manipulate, sense, observe new objects

Cognitive development, learn specific skills

Improve perceptual abilities

Learn about environment

Humans play the most of any species

what decreases play behavior in all species?

hunger

What learning pattern is FAP?

Restricted

Learning vs cognition

Learning = tool to OBTAIN info, needs to happen before cognition

Cognition = ability to USE info

Coleids and Corvids Learning

Distantly related, but have same behavior

Learn similarly bc they have same environmental needs

Episodic memory

Animal Learning

Process in which animal benefits from experience, so that behavior better suited to environment

Types of learning

Habituation

Kin recognition

Imprinting

Spatial Learning

Associative Learning: Classical and Operant conditioning, aversions

Social Learning: imitation, teaching

Cultural Learning

Insight Learning

Tool use

Habituation

Hydra in petri dish eventually learn to ignore tapping

Kin recognition

different treatment of relatives

Mice huddle with siblings and not strangers

Belding’s ground squirrels recognize sisters even when reared apart

Spatial Learning

Involves hippocampus

Chickadee hippocampus size changes depending on food availability

Clark’s nutcrackers

Meadow (non-mono) moles have better spatial memory to search for a bunch of females

Female cowbirds have larger hippocampus for nests, offspring

Associative Learning

Association between stimulus and response

Classical, operant conditioning

Classical conditioning

Pavlov trained dogs to salivate at bell

Conditioned stimulus must appear before unconditioned stimulus

Also includes avoidance learning!

Unconditioned stimulus in Pavlov

Food

Unconditioned response in Pavlov

Salivation

Neutral stimulus in Pavlov

Bell

What became conditioned stimulus in pavlov?

Bell, after paired with with unconditioned stimulus of food

What became conditioned response in Pavlov?

Salivation

Blue gonrami fish classical conditioning

Light flash conditioned to be associated w/ females

Albert baby classical conditioning

John Watson and Rosalie Raynor

White rat and scary noise led to fear of rats

Operant conditioning

Behavior voluntarily changd

reinforcement

Fixed ratio, fixed interval, variable ratio, variable interval

Skinner box operant conditioning

rat gains food by pressing lever

Operant conditioning importance

#1 way to train animals

Determines sensory capabilities

Toad operant conditioning

Avoids drone fly

Pig operant conditioning

Taught to turn on TV, shop

Caterpillar operant conditioning

Avoided certain chemical even after it became moth

Rattlesnake operant conditioning

Learned to turn off heat

Fixed ratio

fixed number of reward

Fixed interval

Fixed amount of time between stimulus and reward

Variable ratio

Amount of reward varies

Variable interval

Varying amounts of time between stimulus and reward

Addictive: gambling, ig likes

Hard to get rid of association, resists extinction

Taste aversions

Classical conditioning

Novel foods cause them more

Only animals with varied diets get them, bats don’t

Give obscure foods before chemo to prevent aversions of important food

Garcia Effect

Rats learn to avoid food after having nausea but not after shock

Won’t avoid red rooms if made nauseous

Garcia effect Significance

Associations are specialized

Social Learning

Observing and interacting w/ others

Imitating other individuals

#1 way children learn

Can occur w/o being reinforced (other may not know they are being observed)

European birds observational learning

Opened milk bottles, drank cream off top

Chimpanzee observational learning

youth watching older females pick grubs out of rotting wood

watched elders eat pink corn, never ate blue corn growing up

even adult immigrants only ate pink corn

Observational learning in Japanese macaques

Wash sweet potatoes in sea = clean and salty

One female started and everyone copied

Also rub rocks together

Observational learning in bees

Trained to pull one color tab and habit passed down to next generation

Observational learning and Mineka monkeys

Monkeys in lab = no snake fear

Wild monkeys = great fear of snakes

Monkeys learn fear of snakes by observing others

Infant born in captivity to wild born mother:

-infant alone w/ snake no fear

-then with mother, mother scared, infant scared

Video of monkey fearing snake worked, but not flowers

Why didn’t monkeys learn fear of flowers

genetically pre-wired for some learning, not others

degree of instinct in learning

Why don’t monkeys fear snakes thru association?

Because snake encounters deadly

Human phobias

instinctual fear of spiders, water etc

havent evolved to fear guns, cars everyday dangerous things yet

(observational) Bobo punching doll experiment

Kids watch vids of adult punching dolls

Kid put into room with a bunch of toys and only punched doll

Social learning benefits humans

Evolved to copy adults to survive

We expect adults to teach us

Don’t need to be harmed to learn

Teaching

Cooperative hunters

Tandem running in ants

Meerkats prey handling

Macaques flossing w/ human hair

Orcas knocking seal off ice

Cultural Learning

Bird song and whale song dialects

Social transmittance of behavior among peers and between generations

Insight Learning

Problem solving

Chimps stacking crates to reach bananas, modifying branches for termite extraction

Orangutan baiting chicken

Octopus

Crow creating tools

Most advanced learning

Insight- not all species can do that

tool use

cockatoos using branch as drumstick

gorilla using sticks

black kites use fire

Sleep & Learning

Needed for ALL species

Slow wave sleep deeper= strengthens memories or connections already in progress

REM connects memories to each other

Rats died w/o REM sleep