Lesson 2: The Science of Behavior - Some History and Principles

Question 1

anthropodomorphism

Answer 1

• Literally means “human-shaped”
• The practice of giving animals human characteristics

Question 2

natural selection

Answer 2

Differential survival and/or
reproduction of individuals
that differ in their traits
- Charles Darwin, On the Origin of
Species (1859)

If a particular variation is more advantageous, then individuals with that
variation will reproduce better (be selected for naturally) than other
individuals and so pass more of their genes on to the next generation.

Question 3

we know how natural selection affects behavior: Trinidaninan Guppies

Answer 3

In Trinidad & Tobago, guppy populations vary in predation pressure
- upstream: low predation
- downstream: high predation

Question 4

Fish from high-predation sites have different physical and hysiological characteristics compared to low-predation sites. These might help deal with predators

Answer 4

• Are less brightly colored (harder to see)
• Reach sexual maturity at a younger age
  (less risk of being prey before
  reproducing)
• Produce more, smaller offspring (more
  chances to pass genes to next

Question 5

fish from high-predation sites also show behavioral differences:

Answer 5

• Swim in larger, tighter schools
• Stay farther away from suspected predators and inspect them more often

Question 6

experiment: trinidadian guppies

Answer 6

200 guppies from high-predation
site transferred upstream to low-predation site

Question 7

result: trinidadian guppies

Answer 7

Within 11 years (about 30-
60 generations), the manipulated
population evolved schooling and
predator inspection behaviors
more similar to low-predation
populations than to the ancestral
high-predation population

Question 8

classical ethology

Answer 8

study of how behavior is adaptive

Question 9

comparative psychology

Answer 9

based on the idea that behavior evolved so it can be compared between other species

Question 10

classical ethologists were influenced by the new ideas of natural selection. They wanted to understand how behavior made the anima “fit” for its environment

Answer 10

as a result: they concentrated on field work and inherited behaviors that were clearly subject to natural selection

Question 11

Example of the contributions of the Classical Ethologists:

Answer 11

Fixed Action Pattern” Egg retrieval in the greylag

Question 12

fixed action pattern features:

Answer 12

1. Stereotyped
2. Triggered by sign
   stimulus
3. Plays out to completion

Question 13

Chain-reaction FAPs

Answer 13

Several fixed action patterns
can be strung together creating
very complex behaviors

Question 14

triggering territorial behavior in sticklebacks

Answer 14

• as long as the models had an eye and a red belly – they were showing territorial behavior

Question 15

FAP: grey goose

Answer 15

mamma had to keep doing the action to completion – whenever she notice her egg, or something resembling the sort was out of her nest – she had to do the rolling action to completion

Question 16

chain-reation FAPs: stickleback courtship behavior

Answer 16

• female with eggs
• male responds with zigzag swim and swims
• female follows
• male shows nest entrance and female enters nest
• male then prods females tale while making trembling movements
  female spawns and leaves; male then enters the nest and also spawns

Question 17

Another contribution of ethologists: Manipulation of
environment to understand mechanism (Tinbergen)

Answer 17

• Manipulation: visual cues around nest were
  changed after wasp had left vicinity
• Result: returning wasps followed the visual cue searched first in area with pine cones

Question 18

Another contribution of ethologists: Manipulation of environment to understand mechanism (Tinbergen)

Answer 18

Manipulation: “Cue conflict” experiment: scent vs vision

Result: returning wasps followed the visual cue:
searched first in area with pine cones

Question 19

Comparative Psychologists

Answer 19

• Used animals as models for human
  behavior, especially learning. The word
  ‘comparative’ meant that we could learn
  about humans by comparing them to animals
• Pioneered the use of ‘controlled
  environments’ to reduce variability; did
  mostly lab work so could create those
  controlled environments

Question 20

a classic contribution: classical conditioning

Answer 20

A regular and measurable unlearned
response to an ordinary stimulus becomes
associated with a neutral stimulus –
something really unrelated to the
response. So the response is now a
‘conditioned reflex’

Question 21

behaviorism

Answer 21

• Regarded animal behavior as
  primarily controlled by conditioned
  reflexes
• So behavior was dependent on
  previous experiences – basically the
  environment that the animals grew up
  in
• Skinner boxes: Chambers designed
  to create a very controlled physical
  environment so that during testing the
  only differences were in the
  rewards/punishments offered when

Question 22

nature vs. nurture

Answer 22

Because ethologists and comparative
psychologists tended to focus on different
aspects of behavior, there came to be
opposing views on the relative importance of
genes (nature) and environment (nurture) in
determining behavior

Question 23

Begging in black-headed gulls has four
steps:

Answer 23

1. Chick approaches parent
2. Opens and closes beak several times
3. Chick turns its own head, positions own
   bill & grasps parent’s bill
4. Chick pushes up with body and pulls down
   with bill

This whole process works as a releaser to get
parents to feed the chick. But if chick
fumbles, the parents try harder to get the
chick to beg properly

Question 24

Begging in black-headed gulls was
regarded as an innate behavior and a fixed
action pattern:

Answer 24

Observations suggested that

1. Triggered by sign stimulus (releaser) of
   parental arrival
2. all chicks did this in the same way
   (stereotyped)
3. Seemed to play out to completion though
   were no experimental manipulations to
   verify

Question 25

Why don’t all chicks beg correctly from
the beginning?

Answer 25

Nature argument: they are genetically
programmed to beg in a certain way but
physically too weak right after hatching –
must mature first

Nurture argument: they need
experience, that is, they need to learn how
to position their heads to beg properly

Question 26

chicks begging - manipulation

Answer 26

Manipulation: Raised some
chicks in incubators without a
chance to beg (hand fed) and
allowed others to be raised by
parents

Then had the chicks beg from
a fake parent (stuffed gull)