1. Inquiry into Life Twelfth Edition
Lecture PowerPoint to accompany
Inquiry into Life Twelfth Edition
Sylvia S. Mader
Chapter 32
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. 32.1 Nature versus Nurture: Genetic Influences
Behavior
Any action that can be observed and described
Genes, to a degree, control behavior

3. 32.1 Nature versus Nurture: Genetic Influences
Experiments with Lovebirds, Snakes, and Snails
Lovebird Nesting Behavior
Fischer lovebirds, Agapornis fischeri, cut strips from leaves and carry them to their nest site
Peach-face lovebirds, Agapornis roseicollis, also cut strips but tuck them into their rump feather and carry them that way
Hybrid lovebirds exhibit intermediate behavior. They cut strips and try to tuck them into feathers, but are unsuccessful
These studies support the hypothesis that behavior has a genetic basis.

4. Nest Building Behavior in Lovebirds

5. 32.1 Nature versus Nurture: Genetic Influences
Experiments with Lovebirds, Snakes, and Snails
Garter Snake Experiments
Genetic role in food preference
Inland populations of garter snakes are aquatic and feed in the water on fish and frogs
Coastal populations are terrestrial and feed on slugs
In the laboratory, inland snakes refused slugs, while coastal snakes readily accepted them
Hybrid snakes exhibited intermediate acceptance of slugs as food
This study suggests a genetic basis for feeding preference

6. Feeding Behavior in Garter Snakes

7. 32.1 Nature versus Nurture: Genetic Influences
Experiments with Lovebirds, Snakes, and Snails
Garter Snake Experiments
Determined that sensory receptors are specific for prey
Researchers presented baby snakes with slug extract on cotton swabs and then counted the number of tongue flicks
Coastal snakes had a higher number of tongue flicks than inland snakes
Apparently, coastal snakes have many receptors on their tongues for taste and smell of slugs, inland snakes do not
A genetic difference between the two populations results in a physiological difference in nervous systems.

8. 32.1 Nature versus Nurture: Genetic Influences
Experiments with Lovebirds, Snakes, and Snails
Snail experiments
Show role of endocrine system in behavior
ELH- egg-laying hormone was isolated in Aplysia snails
ELH controls all aspects of egg laying behavior
After mating, snail pulls egg string with mouth, winds it in a loose ball, and attaches it to an object
When given ELH, snail exhibits all behaviors even without mating

9. 32.1 Nature versus Nurture: Genetic Influences
Experiments with Humans
Twin Studies
Look at characteristics of twins raised apart
Many share common preferences in food, activity patterns, and mate selection

10. 32.2 Nature versus Nurture: Environmental Influences
Environmental influences also affect behavior
Fixed Action Patterns (FAP): specific behaviors elicited by a sign stimulus
Learning: A durable change in behavior brought about by experience

11. 32.2 Nature versus Nurture: Environmental Influences
Learning in Birds

12. 32.2 Nature versus Nurture: Environmental Influences
Learning in Birds
Imprinting: a simple form of learning
Young birds follow the first moving object they see
Sensitive period: time during which imprinting may occur
Social interactions between parent and offspring during the sensitive period are important
Young birds are sensitive to parents vocalization even before hatching

13. 32.2 Nature versus Nurture: Environmental Influences
Learning in Birds
Song Learning
White-crowned sparrows: species-specific song with different dialects; experiments show learning plays a role
Birds that heard no songs: sang an undeveloped song as adults
Birds that heard species song: sang in that dialect as long as tape was played during a sensitive period
Birds that had adult tutor: sang the tutor’s song even if a different species and no matter when tutoring began

14. 32.2 Nature versus Nurture: Environmental Influences
Associative Learning
A change in behavior that involves an association between two events.
Classical Conditioning
The presentation of two different types of stimuli at the same time causes an animal to form an association between them.
Operant Conditioning
A stimulus-response connection is strengthened

15. Classical Conditioning

16. 32.2 Nature versus Nurture: Environmental Influences
Associative Learning
Operant Conditioning
Training an animal by rewarding it

17. 32.3 Adaptive Mating Behavior
Sexual Selection: adaptive changes that increase ability to attract a mate
Biological Fitness: ability to produce surviving offspring

18. 32.3 Adaptive Mating Behavior
Female Choice
Female animals produce few eggs, choosing a mate is a serious consideration.
Two Hypotheses:
Good Genes Hypothesis: females choose mates on basis of traits that improve survival
Run-away Hypothesis: females choose mates in bases of traits that improve appearance

19. 32.3 Adaptive Mating Behavior
Female Choice
The plumage of the male Raggiana birds of paradise may signal health and vigor to the females.

20. 32.3 Adaptive Mating Behavior
Male Competition
Males can produce many offspring because continuously produce sperm in large numbers
Less time and energy invested in reproduction
Males compete to inseminate as many females as possible

21. 32.3 Adaptive Mating Behavior
Male Competition
Cost / Benefits
Baboons have dominance hierarchies. Dominant males mate more often than subordinates. Yet the dominant male is more likely to be in fights, therefore increasing the chance of injury.
Males red deer stags compete for a harem of a particular territory. The harem master is large and powerful with little body fat. Little body fat increases the chance of starvation if food is scarce.

22. A Male Baboon Displaying Full Threat

23. Competition Between Male Red Deer

24. 32.3 Adaptive Mating Behavior
Mating in Humans
Human Males Compete
Women invest more time and energy in a child biologically
Nine month pregnancy and then lactation
Men only need to contribute sperm during sex act
Result: men are more available for reproduction than women
Because more men are available, they must compete
Humans are dimorphic: men are larger and stronger likely as result of past selection by females
Males pay a price. The average life span is seven years less than females.

25. 32.3 Adaptive Mating Behavior
Mating in Humans
Females Choose
In one study, the ability to achieve financial success was found to be the most preferred trait by females
Other studies have shown that facial body symmetry is important
Men Also Have a Choice
Men prefer youthfulness and attractiveness in females, signs that their partner can provide them with children.
By choosing younger women, older men can increase their fitness.

26. 32.4 Sociobiology and Animal Behavior
Sociobiology applies the principles of evolutionary biology to the study of social behavior in animals.
Hypothesis: Living in a society has a greater reproductive benefit than reproductive cost.

27. 32.4 Sociobiology and Animal Behavior
Benefits of Group Living
Helps an animal avoid predators, rear offspring, and find food.
Disadvantages to Group Living
Competition among members of the group for resources and exposes group members to illnesses and parasites.

28. 32.4 Sociobiology and Animal Behavior
Sociobiology and Human Culture
Humans live in organized societies.
The culture of a human society involves a wide spectrum of customs.
The earliest organized societies may have been the “hunters-gatherers.”
A predatory lifestyle likely encouraged the evolution of intelligence and the development of language.

29. 32.4 Sociobiology and Animal Behavior
Altruisms versus Self-Interest
Altruism includes behaviors that sacrifice the individual for the benefit of the group
Inclusive fitness of an individual includes personal reproductive success as well as that of relatives
Measured by how many genes individual contributes to next generation
Helpers at the Nest
Minimal short-term reproductive sacrifice made to maximize future reproductive potential
Helper contributes to survival of kin

30. Inclusive Fitness

31. 32.5 Animal Communication
Communication: An action by a sender that influences the behavior of the receiver
Chemical Communication: Pheromones
Powerful chemical signals passed in low concentration
May be released into the air or used in territory marking
Auditory Communication
Very rapid and can be modified for specific situations
Visual Communication
Most used by diurnal species-must be able to be seen
Plumage, courtship “dances”, aggressive displays, etc.
Tactile Communication
Occurs when one individual touches another

32. Use of a Pheromone (Chemical Communication)

33. A Chimpanzee with a Researcher (Auditory Communication)

34. Visual Communication

35. Communication Among Bees (Tactile Communication)