1. Chapter 51
Animal Behavior

2. Proximate and Ultimate Causes of Behavior
Behavioral ecologists distinguish between proximate and ultimate causes of behavior
The scientific questions that can be asked about behavior can be divided into two classes
Those that focus on the immediate stimulus and mechanism for the behavior (proximate causes)
Those that explore how the behavior contributes to survival and reproduction (ultimate causes)

3. What Is Behavior? Behavior Is what an animal does and how it does it
Includes muscular and nonmuscular activity
Figure 51.2
Dorsal fin
Anal fin

4. Proximate and Ultimate Causes of Behavior
Proximate, or “how,” questions about behavior
Focus on the environmental stimuli that trigger a behavior
Focus on the genetic, physiological, and anatomical mechanisms underlying a behavioral act
Ultimate, or “why,” questions about behavior
Address the evolutionary significance of a behavior

5. A fixed action pattern (FAP)
Fixed Action Patterns
A fixed action pattern (FAP)
Is a sequence of unlearned, innate behaviors that is unchangeable
Once initiated, is usually carried to completion
A FAP is triggered by an external sensory stimulus
Known as a sign stimulus

6. In male stickleback fish, the stimulus for attack behavior
Is the red underside of an intruder
Figure 51.3a
(a) A male three-spined stickleback fish shows its red underside.

7. When presented with unrealistic models
As long as some red is present, the attack behavior occurs
Figure 51.3b
(b) The realistic model at the top, without a red underside, produces no aggressive response in a male three-spined stickleback fish. The other models, with red undersides, produce strong responses.

8. Proximate and ultimate causes for the FAP attack behavior in male stickleback fish
Figure 51.4
ULTIMATE CAUSE: By chasing away other male sticklebacks, a male decreases the chance that eggs laid in his nesting territory will be fertilized by another male.
BEHAVIOR: A male stickleback fish attacks other male sticklebacks that invade its nesting territory.
PROXIMATE CAUSE: The red belly of the intruding male acts as a sign stimulus
that releases aggression in a male stickleback.

9. Imprinting is a type of behavior
That includes both learning and innate components and is generally irreversible
Imprinting is distinguished from other types of learning by a sensitive period
A limited phase in an animal’s development that is the only time when certain behaviors can be learned
An example of imprinting is young geese
Following their mother

10. There are proximate and ultimate causes for this type of behavior
Figure 51.5
BEHAVIOR: Young geese follow and imprint on their mother.
PROXIMATE CAUSE: During an early, critical developmental stage, the young geese observe their mother moving away from them and calling.
ULTIMATE CAUSE: On average, geese that follow and imprint on their mother receive more care and learn necessary skills, and thus have a greater chance of surviving than those that do not follow their mother.

11. Many behaviors have a strong genetic component
Innate Behavior
Many behaviors have a strong genetic component
Biologists study the ways both genes and the environment
Influence the development of behavioral phenotypes
Behavior that is developmentally fixed
Is called innate behavior and is under strong genetic influence

12. These types of movements
Directed Movements
Many animal movements
Are under substantial genetic influence
These types of movements
Are called directed movements

13. Kinesis
A kinesis is a simple change in activity or turning rate in response to a stimulus
Sow bugs become more active in dry areas and less active in humid areas
Figure 51.7a
Dry open area
Moist site under leaf
(a) Kinesis increases the chance that a sow bug will encounter and stay in a moist environment.

14. Taxis
A taxis is a more or less automatic, oriented movement toward or away from a stimulus
Many stream fish exhibit positive rheotaxis where they automatically swim in an upstream direction
Direction
of river
current
(b) Positive rheotaxis keeps trout facing into the current, the direction from which most food comes.
Figure 51.7b

15. Many features of migratory behavior in birds
Migration
Many features of migratory behavior in birds
Have been found to be genetically programmed
Figure 51.8

16. Animal Signals and Communication
In behavioral ecology
A signal is a behavior that causes a change in another animal’s behavior
Communication
Is the reception of and response to signals
Animals communicate using
Visual, auditory, chemical, tactile, and electrical signals
The type of signal used to transmit information
Is closely related to an animal’s lifestyle and environment

17. Chemical Communication
Many animals that communicate through odors emit chemical substances called pheromones
When a minnow or catfish is injured, an alarm substance in the fish’s skin disperses in the water, inducing a fright response among fish in the area
Figure 51.9a, b
(a) Minnows are widely dispersed in an aquarium before an alarm substance is introduced.
(b) Within seconds of the alarm substance being introduced, minnows aggregate near the bottom of the aquarium and reduce their movement.

18. The Environment Influences Behavior
Environment, interacting with an animal’s genetic makeup, influences the development of behaviors
Research has revealed
That environmental conditions modify many of the same behaviors

19. Learning is the modification of behavior
Based on specific experiences
Learned behaviors
Range from very simple to very complex

20. Habituation Habituation
Is a loss of responsiveness to stimuli that convey little or no information

21. Spatial learning is the modification of behavior
Based on experience with the spatial structure of the environment

22. Cognitive Maps A cognitive map
Is an internal representation of the spatial relationships between objects in an animal’s surroundings

23. In associative learning
Animals associate one feature of their environment with another

24. Classical Conditioning
Classical conditioning is a type of associative learning
In which an arbitrary stimulus is associated with a reward or punishment
Before stimulus
Influx of water alone
Influx of alarm substances
Influx of pike odor
Day 1
Day 3
Control group
Experimental group
Experimental group
Relative activity level
Figure 51.15

25. Operant conditioning is another type of associative learning
In which an animal learns to associate one of its behaviors with a reward or punishment
Figure 51.16

26. Cognition and Problem Solving
Cognition is the ability of an animal’s nervous system
To perceive, store, process, and use information gathered by sensory receptors

27. Behavior and Evolution
Behavioral traits can evolve by natural selection
Because of the influence of genes on behavior
Natural selection can result in the evolution of behavioral traits in populations
When behavioral variation within a species
Corresponds to variation in the environment, it may be evidence of past evolution

28. Variation in Prey Selection
Differences in prey selection in populations of garter snakes
Are due to prey availability and are evidence of behavioral evolution
Figure 51.18a, b
(a) A garter snake (Thamnophis elegans)
(b) A banana slug (Ariolimus californicus); not to scale

29. Variation in Aggressive Behavior
Funnel spiders living in different habitats
Exhibit differing degrees of aggressiveness in defense and foraging behavior 50
40
30
20
10 0
Time to attack (seconds)
Field
Lab-raised
generation 1
generation 2
Desert grassland population
Riparian population 60
Population
Figure 51.19

30. Behavior and Natural Selection
Natural selection favors behaviors that increase survival and reproductive success
The genetic components of behavior
Evolve through natural selection
Behavior can affect fitness
Through its influence on foraging and mate choice

31. Optimal foraging theory
Foraging Behavior
Optimal foraging theory
Views foraging behavior as a compromise between the benefits of nutrition and the costs of obtaining food

32. Mating Behavior and Mate Choice
Is the product of a form of natural selection call sexual selection
The mating relationship between males and females
Varies a great deal from species to species
In many species, mating is promiscuous
With no strong pair-bonds or lasting relationships

33. Sexual Selection and Mate Choice
In intersexual selection
Members of one sex choose mates on the basis of particular characteristics
Intrasexual selection
Involves competition among members of one sex for mates

34. Such competition may involve agonistic behavior
An often ritualized contest that determines which competitor gains access to a resource
Figure 51.30

35. Many social behaviors are selfish Natural selection favors behavior
The concept of inclusive fitness can account for most altruistic social behavior
Many social behaviors are selfish
Natural selection favors behavior
That maximizes an individual’s survival and reproduction

36. On occasion, some animals
Altruism
On occasion, some animals
Behave in ways that reduce their individual fitness but increase the fitness of others
This kind of behavior
Is called altruism, or selflessness

37. In naked mole rat populations
Altruism
In naked mole rat populations
Nonreproductive individuals may sacrifice their lives protecting the reproductive individuals from predators
Figure 51.33

38. Altruistic behavior can be explained by inclusive fitness
The total effect an individual has on proliferating its genes by producing its own offspring and by providing aid that enables close relatives to produce offspring

39. Kin selection is the natural selection
That favors this kind of altruistic behavior by enhancing reproductive success of relatives

40. Mean distance moved from natal burrow (m)
Kin Selection
An example of kin selection and altruism
Is the warning behavior observed in Belding’s ground squirrels
Male
Female
Age (months)
Mean distance moved from natal burrow (m)
300
200
100 2 3 4 12 13 14 15 25 26
Figure 51.35