Unit 3: Biological Level of Analysis

1. Unit 3: Biological Level of Analysis Day 12: Evolutional Aspects

2. Outcome(s): • Discuss through a Socratic seminar the extent to which genetics influence behavior • Examine evolutionary explanations of behavior to utilize as evidence in a Socratic seminar • Discuss ethical considerations in research into genetic influences on behavior

3. Agenda: • Warm Up • Guided Notes: Evolution & Biological LoA • Discussion on the role of genetics and evolution on our behavior: why do men cheat on their wives? • Develop Discussion Questions • Socratic Seminar • ERQ – Evolution & Biological LOA

4. Warm Up • Thinking Map: Evolution & Biological Level of Analysis

5. Theory of Evolution & Charles Darwin • Theory of evolution: those who adapt best to the environment will have a greater chance of surviving, having children, and passing on their genes to their offspring • Theory of natural selection: those members of a species who have characteristics which are better suited to the environment will be more likely to breed, and thus to pass on these traits • On the Origin of Species – the theory of adaptation: the result of natural selection is that the species develop characteristics that make it more competitive within its own environment

6. Studying Evolution • Professor Tetsuro Matsuzawa (2007) • Kyoto University in Japan • Aim: to examine spatial memory in young chimps • Methods: three pairs of chimps, taught to recognize numerals 1-9 on computer monitor • Chimps and human participants later seated at a computer terminal where numerals flashed on a touch-screen in random sequence. The participant had to remember which numeral appeared in which location, and touch the squares in the appropriate sequence. • Human participants made many errors, accuracy decreased as numbers replaced with blank squares more quickly • Chimps had remarkable memory for spatial distribution with no difference shown for shorter durations • Why? Psychologists argue that it is a necessary adaptation for chimps to have this type of memory so that they can remember where food (and dangers) are in the rainforest • http://www.youtube.com/watch?v=fzUyX5kezb0

7. Evolutionary Psychology • Grounded in the principle that as genes mutate, those that are advantageous are passed down through a process of natural selection • Attempts to explain how human behaviors can be a testimony to the development of our species over time

8. Studying Evolutionary Psychology • Dan Fessler • Research at University of California at Los Angeles (UCLA) on disgust(2006) • Main argument: emotion of disgust allowed our ancestors to survive long enough to produce offspring, who in turn passed the same sensitivities on to us • Investigated nausea experiences by women in first trimester of pregnancy • Infusion of hormones lowers the expectant mother’s immune system so as to not fight the new foreign genetic material in her womb • Hypothesis: nausea response helps compensate for the suppressed immune system • Methods: • 496 healthy pregnant women between the ages of 18-50 and asked them to consider 32 potentially stomach sickening scenarios (ex: stepping on a worm barefoot, fish hook in finger, maggots on meat in trash can) • First asked questions about questions to see if they were first experiencing morning sickness • Then they ranked how disgusting each scenario was • Findings/Discussion: • Women in 1st trimester scored much higher in disgust sensitivity • When controlled for morning sickness, the response only held for disgusting scenarios involving food, such as the maggot example • Natural selection may have helped compensate for the increased susceptibility to disease during the risky period in pregnancy – disgust is a form of protection against disease

9. Studying Evolutionary Psychology cont. • Curtis et al. (2004) • To test whether there were patterns in people’s disgust responses • Method/participants: • 77,000 participants in 165 countries • Used an online survey in which participants were shown 20 images and to rank level of disgust • Among the 20 images were 7 pairs where one was an infection or harmful to the immune system and the others visually similar but non-infections • Findings/Discussion: • The disgust reaction more strongly elicited for those images that threaten one’s immune system • Disgust reaction decreased with age (disgust reactions higher in younger people) • Once again… this supports the idea of disgust as a key to successful reproduction

10. Things to consider when examining an evolutionary argument (limitations): • Since it may be difficult to test empirically some evolution-based theories, researchers may be susceptible to confirmation bias—that is, they see what they expect to see • Little is known about the behavior of early Homo sapiens, so statements about how humans “used to be” are hypothetical • Evolutionary arguments often underestimate the role of cultural influences in shaping behaviors

11. Ethical Considerations when Researching Genetic Influences on Behavior • Hereditary diseases • Genetic information obtained from research can be problematic for the participant’s family • If misused, genetic information can be stigmatizing and may affect people’s ability to get jobs or insurance • GATTACA: http://www.youtube.com/watch?v=ZppWok6SX88 • Privacy and confidentiality • Informed consent • Can reveal unexpected information that may harm research participants and create undue stress • Evidence of misattributed paternity • Unrevealed adoptions • Carries a gene for a genetic disorder • Some groups may have objections to genetic study as a cultural principle

12. From Day 6 Helen Fischer’s Research on Love • Participants • 32 people madly in love in fMRI • 17 in love was accepted • 15 in love who had been dumped • When you fall in love • A “special meaning” and focus on a person • Intense energy • Dependence • Sexually possessive – Darwinian purpose? • Main characteristics of romantic love: craving, motivation, obsession • Questioning the participants: • What percentage of the day/night do you think about this person? • Last question: would you die for him/her? • Methods • fMRI Brain scans – sweetheart, distractor/neutral, and control • Findings/Discussion • Same brain region activated that is activated when on cocaine • Evolutionary aspect of love: sex drive, romantic love, attachment • http://www.ted.com/talks/helen_fisher_tells_us_why_we_love_cheat.html play until ~7:50

13. Reading • Read The Biology and Psychology of Cheating • When you are done reading… consider the following question: Why do men cheat on their wives? • On a notecard, write: • One thing from the article you might agree with • One thing from the article you might disagree with • Two questions to discuss with classmates

14. Discussion • Discussion Rules • No raising hands • Don’t talk over others • It is a discussion for learning, not a debate

15. Debrief • Possible SAQ/ERQ: Examine one evolutionary explanation of behaviour • Directions: with a partner, create an outline for this ERQ and write the topic sentences of each paragraph

16. Looking Ahead: