Human Evolutionary Psychology - 22 Flashcards
What are evolutionary approaches to studying human behaviour?
Focuses on the reproductive consequences of human behaviour. Often involves study of tribal people with assumption that they are close to our ancestors. Focuses on the adaptiveness of psychological mechanisms that underlie human behaviour: human behaviour produce of psychological mechanisms stemming from natural and sexual selection.
What are the key points on human evolutionary psychology
Human behaviour has been shaped by selection. Our behaviour is influenced by biological predispositions and the social environment (cultural influences/social learning). As our environment changed, psychological traits may be of little or no adaptive value now. Human behaviour is uniquely flexible and most aspects of it are under conscious control.
What is environment of evolutionary adaptedness (EEA)
Pleistocene taken to represent our ancestral environment - early humans living as hunter-gathers in a savannah habitat. Likely features of EEA: hunter/gather scavenging, low population density, small kin-based groups, nomadic or semi-nomadic, high infant mortality and low life expectancy, vulnerability (e.g. predators, disease)
What were adaptive problems faced by hunter-gather ancestors?
Eating the right food, avoiding predators, obtaining mates, caring for offspring, forming alliances, reading other people’s minds. How well an individual solved these problems would have affected their success in passing on genes - therefore expect mental mechanisms for solving these problems to have been selected for.
What occurs in sexual selection in humans?
Sexual dimorphism: important factor likely to be selection on males for success in contests against other males (intra-sexual competition) - but mate choice also important: larger body size and greater upper body strength in males than females. More bodily and facial hair in males. Enlarged breasts and buttocks in females. Human mating systems predominantly polygynous.
What are key forms of intra-sexual competition in animals?
Direct combat: males with large body size/weaponry & impressive displays selected. Sperm competition: males whose sperm successful in fertilising eggs selected.
What is sperm competition in humans?
Competition between sperm from different ejaculates/males for fertilisation of eggs produced by a single female. Human testes size suggests adaption for multi-male mating system - although indicates not as much sperm competition as in e.g. chimps. Penis is longer, thicker and more flexible in human males than in non-human primates. Baker & Bellis found the less time a couple has spent together the more sperm the sale ejaculates (greater risk that female has copulated with another male).
What are patterns of mate choice in humans?
Buss - evidence of consistency in mating preferences across different cultures. Females valued cues to resources acquisition, males valued characteristics signalling reproductive potential.
What is evidence for symmetry in morphological characteristics?
College women sniffed & rated attractiveness of scent of 41 t-shirts worm over night by different men. Women near peak fertility prefer scent of symmetrical men. Male symmetry calculated on basis of ear length, ankle widths and finger lengths.
What is involved in female orgasm and mate choice?
Up-stuck hypothesis: female orgasm functions to suck up sperm during copulation - leads the cervix to gape and dip into the seminal pool.
What is female choice for masculine faces?
Female preferences for masculinised faces are stronger during fertile phase of cycle. Similar effects on preferences for male body shapes, tallness and testosterone related vocal characteristics. Females prefer low voice pitch in camels - associate is with dominance, masculinity and help. Also testosterone levels affect voice pitch.
What do males look for in females?
Men prefer women with intermediate Body Mass Index BMI. BMI strongly linked to health and reproductive potential. Males also prefer neotenous features (resembling newborn infants) in female faces.
What is kin selection?
Resource sharing - genetic relatedness is a major factor determining patterns of alliances, resource sharing and inheritance. Care of genetic offspring versus step-children - indiscrimination of allocation of resources between kin and non-kin is an anomaly in evolutionary terms. Daley & Wilson present evidence that children living with a step-parent are more at risk of physical abuse.
What is reciprocal altruism?
Direct reciprocity is rare in animals but common in humans: recognition of alliance partners, governed by well-defined rules, defection/punishment if alliance partner cheats, status affected by reputation.
