Animal Behavior: Why (and how) do animals do what they do?

1
Animal Behavior Why (and how) do animals do
what they do?
Picture Animal cognition.net
2
Aristotle (384-322 B.C.) Observational work
in zoology
Anatomy
Embryology
Behavior Social organization
Characteristics Vivipary
3
5/13/08 Natural Selection and History
of Animal Behavior

• Lecture objectives
• Understand Darwins theory of evolution by
  natural selection
• Identify the major people and questions that
  guided the development of the modern study of
  animal behavior

4
The views on relationships between species have
progressed over time
5
Darwin set the stage for the study of animal
behavior through his theory of natural selection
6
Evolution by natural selection is inevitable if
3 conditions are met

• Variation
• Heredity
• 3. Differences in reproductive success

x
x
Survival of the fittest
7
Evolution by natural selection acts at the
genetic level
Peppered mothGene for colorhas two alleles
(forms) R, r
RR, Rr
rr
8
Example of natural selection in action moths
in England during the Industrial Revolution
I tawt I taw a peppered moth!
1
Proportion of light moths
0
Brown trunks increase
9
What would a population look like over timeif
one of Darwins 3 conditions is not met?

1. No Variation?
2. No Heredity?
3. No Differences in reproductive success?

10
Biologists often seek to understand behavior
through the lens of natural selection How
does this trait promote reproductive success?

• Logic
• Conditions of n.s. apply to
• So species have been
• So the traits we observe today are a
• So these traits probably exist because

11
Example of Darwinian approach How does
infanticide by male langurs increase the males
reproductive success?
Tendency for infanticide
x
x
No tendency for infanticide
12
Example of Darwinian approach Why might a
(former) mother langur be willing to mate with
this new male?
Tendency to mate
x
No tendency to mate
x
13
How might building an elaborate bower enhance the
reproductive success of male bowerbirds?
14
The history of the study of animal behavior
PavlovThorndikeSkinner
Behaviorism
ComparativePsychology
Aristotle
Darwin
1900
350 B.C.
1859
1973
ModernAnimal Behavior
Ethology
Nobel Prize
Lorenzvon FrischTinbergen
15
Pavlov Classical Conditioning
16
Thorndike and Skinner Operant
Conditioning (Trial-and-error learning)
17
The history of the study of animal behavior
PavlovThorndikeSkinner
Behaviorism
ComparativePsychology
Aristotle
Darwin
1900
350 B.C.
1859
1973
ModernAnimal Behavior
Ethology
Nobel Prize
Lorenzvon FrischTinbergen
18
Karl von Frisch Communication Sensory
abilities in Honeybees
19
Konrad Lorenz (1903-1989) Instinct,
Imprinting Motivation
Form of imprintingWestermarck effect
20
Niko Tinbergen (1907-1988) What features of
the environment do animals respond to?
Fixed action patternsEgg-rolling behavior in
graylag geese
Sign stimuliAggression in 3-spined sticklebacks
Experiments!
21
Behaviorist or Ethologist? You decide!
?
Give me a dozen healthy infantsand my own
specified world to bring them up in and I'll
guarantee to take any one at random and train him
to become any type of specialist I might select
doctor, lawyer, artist, merchant-chief and, yes,
even beggar-man and thief, regardless of his
talents, penchants, tendencies, abilities,
vocations, and race of his ancestors.
22
Behaviorist or Ethologist? You decide!
?
His view Each animal has its own subjective
universe, or way of sensing the world around it.
And as a consequence, different animals, even
ones that share the same physical environment,
might have unique sensory experiences.
23
The history of the study of animal behavior
PavlovThorndikeSkinner
Behaviorism
ComparativePsychology
Aristotle
Darwin
1900
350 B.C.
1859
1973
ModernAnimal Behavior
Ethology
Nobel Prize
Lorenzvon FrischTinbergen
24
The modern study of animal behavior is a
synthesis of behaviorism and ethology

• Behaviorists came to recognize that
• Ethologists came to recognize that

25
The history of the study of animal behavior
PavlovThorndikeSkinner
Context Psychology - Learning
NurtureLabwork Mammals, Pigeons
Behaviorism
ComparativePsychology
Aristotle
Darwin
1900
350 B.C.
1859
1973
ModernAnimal Behavior
Ethology
Nobel Prize
Context Biology - Evolution NatureFieldwork
Insects, bird, fish
Lorenzvon FrischTinbergen
26
Darwin discussion

1. Variation What might maintain this?
2. Heredity Are all traits hereditary?
3. Differences in reproductive success What might
   make some animals be less successful at producing
   offspring?

x
x