More Related Content
What's hot
What's hot (19)
Viewers also liked
Viewers also liked (20)
Similar to Evolutionary psychology - Aggression
Similar to Evolutionary psychology - Aggression (19)
More from G Baptie
More from G Baptie (20)
Recently uploaded
Recently uploaded (20)
Evolutionary psychology - Aggression
- 1. OUTLINE & EVALUATE HORMONAL EXPLANATIONS OF AGGRESSION… (20 MARKS) • A01: • ‘Chemicals that regulate & control bodily functions’ • Testosterone = Androgen (male hormone, released from testes) • 10x higher in males than females (adrenal gland) • 15-25yrs = peak testosterone age and age most likely to commit violent crimes • Animal studies can show effects of removal of testosterone sources (neutering) • Possible links between Low Levels of Cortisol + aggression
- 2. A02 • Higher in athletes from aggressive sports • Higher in more aggressive prison populations (Dabbs, 1995) • Can increase aggression in castrated mice (Wagner) • Can increase anti-social competition in men (Harrison) • Possible link with low cortisol HOWEVER… • Data generated from small, specific (prison) samples • General population shows 0.14 correlation (other factors) • Alternative explanation may be that testosterone increases social dominance…not aggression
- 3. AO3 Gender Reductionist Ethical Guidelines? Nature vs. Nurture Animal Studies Determinsm vs. Free Will Ethnocentricism
- 4. EVOLUTIONARY EXPLANATION OF AGGRESSION UNDERSTANDING OF EVOLUTIONARY PSYCHOLOGY EVOLUTIONARY THEORY APPLIED TO AGGRESSION KEY WORDS: PARENTAL INVESTMENT, CUCKOLDRY, SEXUAL JEALOUSY, ADAPTIVE
- 7. INCLUSIVE FITNESS • ‘Measure of how successful individuals are in passing on a high proportion of their genes to succeeding generations’
- 8. WHAT IS EVOLUTIONARY PSYCHOLOGY? • EP seeks to identify which human psychological traits are evolved adaptations – that is, the functional products of natural selection or sexual selection in human evolution
- 10. EVOLUTIONARY PSYCHOLOGY • All behaviour is rooted in ensuring ‘reproductive success’
- 11. EVOLUTIONARY PSYCHOLOGY • SLT = we can learn to be aggressive • Deindividuation = situations make us aggressive • Institutional = Institutions make you aggressive • Genetic/Neural/Hormonal = Our biology make us predisposed to aggression • Evolutionary = The Ultimate Reason for Aggression
- 12. EVOLUTIONARY AGGRESSION • Why was it ‘adaptive’ to behave aggressively? • How might aggressive behaviour in modern day be associated with reproductive success?
- 13. EVOLUTIONARY PSYCHOLOGY • Lorenz (1966) • Functions of Aggression… • 1. Ensure only the fittest & strongest mates selected for reproduction • 2. Ensure survival of offspring • 3. Distribute a species in a balanced way in territories
- 14. PARENTAL INVESTMENT… • “Any investment by the parent in an individual offspring that increases the chance of offspring survival” • Involves provision of resources, (food, energy, time, territory)
- 15. PARENTAL INVESTMENT… • There is asymmetry in parental investment in humans • Female egg cell is much more costly to produce than male sperm cell • Females must nourish the offspring for 9 months, she is therefore limited by number of offspring • In Western cultures, females breast feed for between 3-12 months
- 16. • Females must be choosier when it comes to potential male mates • Females compete for quality of male mates • Males compete for quantity of female mates 69!2000!
- 17. EVOLUTIONARY PSYCHOLOGY • “Sexual Jealousy” – based on suspected or imminent sexual infidelity
- 18. EVOLUTIONARY PSYCHOLOGY • Sexual Jealousy can be used as a mitigating factor in court • In many cultures, a man has the right to beat or even kill his unfaithful wife • In Western societies, murder charges can be reduced to manslaughter if the male killed another male who was sexually involved with the killer’s wife… this is not the same for women.
- 19. CUCKOLDRY • “Investing in offspring that are not their own” • Females can be certain if a child is their own, males cannot • Therefore males have a greater concern about the fidelity of their mates than females
- 20. CUCKOLDRY RISKS… • Retaliation from male • Abandonment (loss of resources) • Loss of invested resources • Loss of reproductive success
- 21. A01 EVOLUTIONARY EXPLANATION… • Cuckolded men risk losing resources and reproductive opportunity. Males evolved aggressive mate-guarding strategies to prevent being cuckolded. These are driven by sexual jealousy, an adaptation evolved in males to deal with parental uncertainty. Sexual jealousy prevents the female mating with others so it is an adaptive response.
- 22. CUCKOLDRY • Sexual jealousy may have evolved as a solution to these problems… • Buss (1992) • Which is worse? • A) The knowledge that your partner has had sex with someone else • B) The knowledge that your partner has developed a deep emotional bond with someone else
- 23. BUSS (1992) • 85% of women chose option B – deep emotional bond • 60% of men chose option A • (The majority of the 40% of males who had chosen option A had never been in a committed sexual relationship)
- 24. WHICH ROUTE TO TAKE… • 1. Sow your wild oats with lots of women, hoping that at least some of them mother your children… • Or 2. Stick to 1 woman and watch her like a hawk so you can be sure she’s mothering only your children
- 25. SHACKLEFORD (2005) • Claimed that men have evolved ‘mate-retention strategies’ to deter their mate from leaving/cheating. • He found that the more of these strategies seen in a relationship, the more likely female-directed abuse will occur.
- 26. SHACKLEFORD (2005) • 1. Vigilance • 2. Emotional Manipulation • 3. Monopolisation of Time • 4. Possessive Ornamentation
- 27. SHACKLEFORD (2005) • 72% of women who reported partners using ‘direct-guarding’ (not allowing them to talk to other men) required medical attention after an assault by their partner • “Aggression is an adaptive response to ensure reproductive success”
- 28. DALY & WILSON (1988) • Peak reproductive age in males is early 20s • This age is also the most likely age to commit same- sex homicide.
- 29. DALY & WILSON (1988) Same-sex murder rates reflect evolved aggression due to sexual jealousy
- 30. DALY & WILSON (1988) • A lack of resources increases male-male competition and risk of murder…
- 31. DALY & WILSON (1988) • Threat to male status • Females attracted to men with higher status • Therefore men seek status • Loss of male status = loss of potential mates + possibly resources.
- 32. WHAT WE KNOW SO FAR… • Factors affecting reproductive success can increase aggression… • A02 • (Buss – Males – sex>emotional bond) • Shackleford – More mate-guarding = more violence • Daly & Wilson – peak reproductive males = peak violence - More male-male murders than female - Less resources = more male-male murders
- 33. AO3 Gender Reductionist Ethical Guidelines? Nature vs. Nurture Animal Studies Determinsm vs. Free Will Ethnocentricism
- 34. FEMALE AGGRESSION • Studies have found that females will use more ‘Verbal Aggression’ than males… • How can this be explained by Evolutionary Psychology?
- 35. MALADAPTIVE AGGRESSION? • Ghiglieri (1999) • Male lions & cheetahs have been observed killing offspring (usually of rival males) • Reduces Inclusive Fitness (reproductive success) in rivals • More resources and less competition for own offspring • Causes Rival’s lioness to go into ‘oestrus’ (heat) sooner, allowing killer to impregnate them with own offspring.
- 36. OTHER TYPES OF AGGRESSION?
- 37. OTHER TYPES OF AGGRESSION… • Lorenz (1966) • Functions of Aggression… • 1. Ensure only the fittest & strongest mates selected for reproduction • 2. Ensure survival of offspring • 3. Distribute a species in a balanced way in territories
- 38. LORENZ - XENOPHOBIA & GENOCIDE… • Violence towards other cultures is common… • Lorenz believes this is due to ‘Territorial Aggression’ driven by evolved, primal survival tactics.
- 39. XENOPHOBIA & GENOCIDE • Waller (2002) • Humans have evolved living in groups which need defined boundaries creating ‘in-groups’ and ‘out-groups’ • Allows for resources to be shared equally, reduces potential of ‘free- riders’ • Reduces reproductive competition • We have evolved xenophobic attitudes towards out-group members to protect our own • Genocide is the consequence of this xenophobia
- 40. HOWEVER… • Individual Differences (not all men act aggressively towards unfaithful partners) Suggests that violence is not a universal response to sexual jealousy, thus not completely evolutionary • Cultural Differences in Aggressive Behaviour…
- 41. CULTURAL DIFFERENCES IN AGGRESSIVE BEHAVIOUR… • (Buss & Shackleford, 1997) • Yanomami of South America • Male violence is required to attain status • Kung San of Namibia • Aggression leads to irreparable damage of the aggressor
- 42. DESCRIBE & EVALUATE THE EVOLUTIONARY EXPLANATION OF AGGRESSION. (8 + 16 MARKS) • A01 • Lorenz – 3 functions of aggression • Adaptive – Increase reproductive success & thus inclusive fitness • Key words – Sexual Jealousy – Cuckoldry • Mate-Retention Strategies • Male-male competition • Territorial Aggression
- 43. DESCRIBE & EVALUATE THE EVOLUTIONARY EXPLANATION OF AGGRESSION. (8 + 16 MARKS) • A02: • Shackleford – More mate-retention strategies = more violence • (supports notion of sexual jealousy driving aggression) • Daly & Wilson – Age / Male-male homicide / Resources / Status • (supports idea of reproductive competition driving aggression) • Female Aggression = verbal • (females less physical, verbal aggression reduces status and deters males) • Other types of Aggression – Xenophobia (Waller, 2002) • (supports idea that aggression is created by drive for in-group to survive)
- 44. AO3 Gender Reductionist Ethical Guidelines? Nature vs. Nurture Animal Studies Determinsm vs. Free Will Ethnocentricism
Editor's Notes
- Phobias, anorexia, gym, make up, dancing
- Defend food / mates
- Geghis 2000 gravata - 69
- Look in books for examples of each
- Size of females evolved
- Try and write a paragraph now including all key words