Learning A “relatively permanent change in behavior as a result of experience” - what is learning? - which behaviors are learned? - why learn or when will.

LearningA “relatively permanent change in behavior as a result of experience”

- what is learning?- which behaviors are learned?- why learn or when will learning evolve?- evolution of learning and forgetting

A simple experimental example

Can fish learn about predation risk in a body of water through chemical cues?

1) They react with an appropriate anti-predatory behavior

2) They retain this reaction for a period of time

+ +

DW

PO PO

TSE

Farm raisedjuvenile brown trout

Short-term effects

4-days later

21-days later

A “relatively permanent change in behavior as a result of experience”

Eagle alarm

Leopard alarm

Snake alarm

Socially acquiredpredator avoidance

InfantsN=24

Raptors Non-raptors

Goshawk Snake Bateleur Tawny Fish Eagle Eagle Eagle

Vulture Bee-eater

JuvenilesN=53

Raptors Non-raptors

Goshawk Snake Bateleur Martial Crowned Tawny Fish Harrier Owl Eagle Eagle Eagle Eagle Eagle

Vulture Stork Bustard

AdultsN=55

Raptors Non-raptors

Goshawk Snake Martial Crowned Tawny Fish Hawk Owl Eagle Eagle Eagle Eagle Eagle Eagle

Vulture

< 56-10

11-15>15

How do infants come to recognize the association between an alarm calland 1-2 predators?

100%

64%14%

3%4%

Probability of adult alarm calling after infant alarm callby avian species – Reinforcers?

3/4 4/5 5/6 6/7

100

100

100

Responses of infants to playbacks of adult alarm calls

Number of infants responding

correctly incorrectly

Verveteaglealarm

Starlingeaglealarm

Verveteaglealarm

Vervetleopardalarm

Starling eaglealarm

Vervetleopardalarm

habituation

• Vervets habituate to call (learn it’s a false alarm)

• Learning of vervet eagle alarm extends to starling raptor alarm

• But learning does not extend betweenclasses of predators

Learning curves associated with locating and extracting nectar as a function of experience

detections

Simple recognition learning –

In this example, birds learnwho their neighbors are and associate them to a particular place – the territory boundary

songs per min

“Dear-enemy” effect

Learning is a proximal cause of animal behavior because learning itself is a strategy/trait subject to natural selection

Under this perspective we can redefine learning as a tool that allows individuals to adjust their behavior to the local state of their world – i.e., to the set of local spatial, temporal, and social circumstances

Learning is a proximal cause of animal behavior because learning itself is a strategy/trait subject to natural selection

Under this perspective we can redefine learning as a tool that allows individuals to adjust their behavior to the local state of their world – i.e., to the set of local spatial, temporal, and social circumstances.

- Where is food and what make-up is it? - Who are my territorial neighbors – do I recognize them? - What predators are nearby and what are their intentions?

Learning is a proximal cause of animal behavior because learning itself is a strategy/trait subject to natural selection

Under this perspective we can redefine learning as a tool that allows individuals to adjust their behavior to the local state of their world – i.e., to local spatial, temporal, social, and causal relationships

Where is food and what make-up is it?Who are my territorial neighbors – do I recognize them? What predators are nearby and what are their intentions?

- recognizing kin from non-kin- social hierarchies: recognizing strangers from non-strangers- remembering past interactions (winners and losers) - recognizing high quality mates

Within-lifetime Predictability

Low

High

Between-generationPredictability

learn

ignore experience

ignore experience

ignore experience

Dave Stephen’s Model

Low

experience in the past is not useful

High

it is useful

If offspring’s environmentis nearly identical, fixed genetic transmission isfavored over costly learning

experience is useful within generation, and learning anew is favored each generation

Evolution of Learning

Summary:

- Learning is a likely element of proximal causation for most of the behaviors discussed in the remainder of the class

- More importantly, the entire learning process is under evolutionary selection pressure

- We can broadly understand the evolution of learning in response to thepredictability of an organism’s environment in its own lifetime and beyond

or we can ask detailed questions about the evolution of learning under specific contexts with a cost-benefit analysis ….

e.g. members of each new generation may find food in different places,but there is always value in being able to learn where food is

learnLow

between-generationpredictability

High within-lifetime predictability

The conditions that bring about learning should be reliable correlates of the state of the world the animal needs to adjust to

This differs from classical views of learning that assumed:(1) The ability to learn is an unadulterated good(2) Learning abilities are human-like: general and unlimited

Dave Stephen’s Model

Br dParasitism

Tailorbird feeding a Plaintive Cuckoo

Brown-headed Cowbird