UNIT 3: BIOLOGICAL LEVEL OF ANALYSIS Day 12: Evolutional Aspects

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

Agenda: 1. Warm Up 2. Guided Notes: Evolution & Biological LoA 3. Discussion on the role of genetics and evolution on our behavior: why do men cheat on their wives?  Develop Discussion Questions  Socratic Seminar 4. ERQ – Evolution & Biological LOA

Warm Up  Thinking Map: Evolution & Biological Level of Analysis

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

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 

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

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 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 1 st 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

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

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

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:  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

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 why_we_love_cheat.htmlhttp:// why_we_love_cheat.html play until ~7:50 From Day 6

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

Discussion  Discussion Rules 1. No raising hands 2. Don’t talk over others 3. It is a discussion for learning, not a debate

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

Looking Ahead: