INTRODUCTION TO PSYCHOLOGY

1. INTRODUCTION TO PSYCHOLOGY Chapter 2 Evolution and the Biological Roots of Behavior

2. At the end of this Chapter you should be able to: Learn about evolutinary roots of motivated behavior Learn about Eating Learn about Threat and Agression Learn about Mating

3. Charles Darwin Rattled the world with his theory of natural selection Wrote “Origin of Species”

4. Darwin’s Theory of Evolution More individuals are born in each species No two individuals are identical. Certain differences among individuals are adaptive. And more likely to survive and reproduce Some adaptive differences among individuals are inherited.

5. Darwin’s Theory of Evolution Not enough resources to support all individuals. A struggle for existence occurs and who possess the most adaptive characteristics, win the struggle.

6. Darwin’s Theory of Evolution Individuals who survive and reproduce pass on their adaptive characteristics to their offspring, Over many generations, this process may result in the creation of new species.

7. Evolution of Behavior Many aspects of who we are are rooted in our genetic heritage. Identical twins inherit exactly the same genetic pattern. Identical twins usually end up more similar to each other in their personalities and preferences than are other siblings, even when they are raised apart (in different households).

8. Evolution of BehaviorThe Comparative Method We can get further insights into the evolution of behavior by comparing human behavior to other organisms. Other animals are less likely to be influenced by cultural factors or complex decision-making. Therefore finding parallels with other species would suggest a smaller role for these human (cultural) influences.

9. Human Behavior Eating Threat and Aggression Mating

10. REVISION – NATURAL SELECTION

11. REVISION – NATURAL SELECTION

12. QUIZ !!!

13. How did your body react… When I first announced the quiz? After you were informed that it would notbe taking place?

14. The Nervous System Central Nervous System (CNS) The brain and spinal cord Peripheric Nervous System (PNS) System of nerves outside of the brain andspinal cord Send control to the glands and smoothmuscles Controls internal organs, usually not undervoluntary control

15. Autonomic Nervous System The peripheral nervous system is subdivided into the: sensory-somatic nervous system and the autonomic nervous system Two branches Sympathetic Parasympathetic

16. Nervous system Peripheral Central (brain and spinal cord) Autonomic (controls self-regulated action of internal organs and glands) Somatic (controls voluntary movements of skeletal muscles) Sympathetic (arousing) Parasympathetic (calming)

18. Sympathetic Nervous System Triggered when bodytemperature is too low Revives up body activityto prepare forrigorous activity

19. Sympathetic Nervous System Increased heart rate Slowing down of peristalsis (rhythmic contractions of intestines), so not using energy during digestion Vasoconstriction Contraction of skins capillaries

20. Parasympathetic Nervous System Triggered whenbody’s temperatureistoo high Restored body’s internal activities

21. Parasympathetic Nervous System Cardio slowing Speeds up peristalsis Vasolidation Widening of skin’s capillaries

22. Stimulus Body prepares for response Body returns to normal

23. Human Behavior Threat and Aggression Mating

24. Threat and Aggression

25. Threat and Aggression • What happens biologically when we feel threathened? • Self-protection • The Emergency Reaction: Fight or Flight • Intense arousal serves as an emergency reaction that mobilizes the animal for a crisis.

26. Threat and Agression Internal adjustments necessary to respond to threat in environment When threat detected: Sympathetic branch of ANS activated Prepares body for immediate, intense activity. Surge of adrenaline released

27. Threat and Agression Male aggression and hormones: The male is the far more aggressive sex. This gender difference holds only for physical aggression. Testosterone (the male sex hormone) is associated with physical aggressiveness in many species.

28. Threat and Agression Territoriality: Acquisition and protection of resources, usually territory: source of most aggression Often expressed in humans as “personal space” preferences Vary by culture; much is learned

29. Threat and Agression Male versus female aggression: Males use physical aggression (pushing and punching). Females use social aggression (spreading gossip and rumors, isolating unwanted friends).

30. Threat and Agression Learning to be aggressive? 1. Explicit learning: someone demands or teaches us 2. Implicit: we observe 3. Seems to be causal; when we observe violence, we become violent

31. Threat and Agression • Is aggression inevitable? • Dominance hierarchy: who is the strongest in the group? Assigned status is a limit on aggression.

32. Threat and Aggression A video on Threat and Aggression ( A different point approach )

33. Nature-Nurture Debate

34. Nature-Nurture Debate Relative importance of an individual's innate qualities (“nature”) versus personal experiences (“nurture”) in determining individual differences in behavioral traits.

36. Human Behavior Eating Threat and Aggression Mating

37. Mating Appearance Matching Gender Differences

38. Appearance Humans value attractiveness in a partner Who is attractive? Isn’t beauty the eye of the beholder?

39. Facial Appereance Cross-culturally Shiny hair No visible deformities Clear skin Symmetrical face Average face (slight deviation can help) Developmentally

40. Infants Infants as young as 3-months-old look longer atadult-rated attractive faces

41. Pictures? 12-month-olds interact more positively withadult wearing “attractive” mask.

42. Why is there a preference forattractiveness? Indication of health

43. The Matching Hypothesis There is a strong correlation between thelevel of attractiveness of two partners Prefer partners similar to themselves

45. The Matching Hypothesis Attractiveness Personality Race Ethnic origin Social status Education level Family background Income Religion Habits

46. Gender differences in mateselection / Animals Females Decide when to mate and mating partner Most physical investment in breeding Males Advertise sexual availability

47. Gender differences in mateselection / Humans Man seeking woman… Physical attractiveness Healthy and fertile Youth More reproductive years

48. Gender differences in mateselection / Humans Man seeking woman… Kindness Intelligence Less value of commitment More jealous by sexual disloyalty

49. Gender differences in mateselection / Humans Women seeking men… Older Social and financial status Better ensures offspring’s survival

50. Gender differences in mateselection / Humans Women seeking men… Kindness Intelligence More value of commitment More jealous of emotional disloyalty