Evolutionary Psychology A very basic introduction to the topic This is a tough topic to teach! The Darwin Awards This maybe a bit much for some students. Use this carefully, after all, a life was lost or someone may have been injured. The Darwin Awards 2010 To begin with, some definitions: What What is evolution? is evolutionary psychology? What is evolution? Biology’s definition - change in the gene pool of a population from generation to generation by such processes as mutation, natural selection and genetic drift Evolution (also known as biological or organic evolution) - the change over time in the proportion of individual organism differing in one or more inherited traits. A trait is a particular characteristic that is the result of gene-environment interactions. Evolutionary Psychology- the study of the psychological adaptations of humans to the changing physical and social environment, especially of changes in brain structure, cognitive mechanisms, and behavioral differences among individuals. Peter Gray of Boston College notes this misconception about evolution: Students may believe that “lower species” are on their way to becoming humans or that evolution occurs in order to meet future conditions or higher moral purposes. Reference: Myers, David Psychology Teacher’s Guide, Ch. 3 p.7 Grays says, no! His example is the evolution of beak thickness in finches on the Galapagos Archipelago. Over many years of drought, the birds evolved thicker beaks that could crack harder seeds. Then over years of heavy rains, the same species evolved thinner beaks for eating softer seeds the moisture produced. What was fit for one situation was not fit in the other. So, The species did not anticipate the change in climate by developing characteristics that would meet the situation in advance. Gray suggests that the evolutionary perspective is useful in raising the “why of behavior” question that is central to the discipline of psychology. Gray continues to explain If one can answer the “why” then one can understand the distinction between proximal causation (immediate inducers of behavior) and ultimate causation (the evolutionary advantage served by the behavior) Both explanations show how different perspectives are complementary. Gray also notes That the evolutionary perspective does not equal psychopathology. Some behaviors have potential evolutionary value For example, “Why do young children resist going to bed? Are they just being spoiled ? Well, perhaps not. In some cultures, bedtime protest is absent. Why? See article, nytimes.com “A Darwinian Look at a Wailing Baby” P. 112 Some may answer, that the child fears being alone in the dark In hunting and gathering days, being alone in the dark was a very real fear. Children who protested, attracted adult attention and were more likely to survive. In present day hunting and gathering societies, putting a child to bed alone is child abuse. Thus, perhaps this behavior is really one that has evolved for survival. Reference: Gray, P. (1996) Incorporating evolutionary theory in the teaching of psychology. Teaching of Psychology 207-214. Let’s try a few questions Questions designed by Bernard Weiner to introduce a few basic principles of evolutionary psychology. Weiner, B. (1992) Human Motivation: Metaphors, theories and research. Newbury Park, CA: Sage Publications Questions #1-2 1) You are on a boat that overturns. It contains your 5 year-old and your 1-year old children (of the same sex). The boat sinks an you can save only one. Whom do you choose to save? 5 year old 1 year old 2) That same boat contains your 40 year old and 20 year old children (both of the same sex). Neither can swim. As the boat sinks, whom do you chose to save? 40 year old 20 year old They Say #1 #2 The 5 year old The 20 year old Why? Why? More likely to survive and reproduce More likely to survive and reproduce The Questions #3-4 3) Have you (or would you) rather marry someone older or younger than yourself ? 4) Of the following six, which three are most important in the selection of your mate? Good financial prospects Good looks A caring and responsible personality #3 The answer depends on male vs. female response Physical attractiveness Ambition and industriousness An exciting personality And “they” said MALES: Of the following six, which three are most important in the selection of your mate? Good looks FEMALES: Of the following six, which three are most important in the selection of your mate? Good financial prospects A caring and responsible personality Ambition and industriousness Physical attractiveness An exciting personality To define evolutionary psychology A branch of biology that studies brains, how brains process information and how the brain’s information processing programs generate behavior. ~as defined by K. Minter, Austin, TX Why Students Love Evolutionary Psychology. . . And How To Teach It David Buss, PhD University of Texas, Austin From his article in Psychology Teacher Network Fall 2010 Content is taken from the PTN article and other sources quoting Dr. Buss. Further references my be derived from Evolutionary Psychology: The New Science of the Mind (Buss, 2011) Dr. Buss states evolutionary psychology has high interest due to real-world applicability Topics students are interested in include mate-selection, conflict between the sexes, aggression, cooperation, parent-offspring relationships and status hierarchies Evolutionary psychology provides a compelling “metatheory.” (overarching idea to understand all introductory psychology topics) Main tenets of Evolutionary Psychology The fundamental basis of evolutionary psychology dates back to Darwin’s (1859) theory of natural selection which has 3 basic components Variation (individual differences within a species) Inheritance (passed down reliably from parents to child) Differential reproductive success (solves problems of survival) Evolutionary Psychology has historically been applied to anatomy and physiology. Now the ideas can be applied to psychological, strategic and behavioral adaptations which help to solve the specific problems of survival and reproduction and many issues as well. To quote Dr. Buss, the main tenets of evolutionary psychology are 1) All manifest behavior is a function of psychological mechanisms, in conjunction with environmental and internal inputs to those mechanism. 2) All psychological mechanisms owe their existence, at some basic level of description, to evolutionary processes (scientifically, no other known causal processes exist for creating complex organic mechanisms) 3) Natural selection and sexual selection (Darwin’s theories) are the most important evolutionary processes responsible for creating psychological adaptations. Note: Natural selection- those traits and characteristics that help survival will remain; those that do not help survival will die out over time (be “selected” out) More tenets 4) Evolved psychological mechanisms can be described as information processing devices (input, decision rules or other transformation procedures and outputs). 5) The output of psychological adaptations can be physiological activity, information that serves as input to other psychological mechanisms or manifest behavior. 6) Psychological adaptations are housed in the brain. 7) Psychological adaptations are functional, that is “designed” to solve statistically recurrent adaptive problems confronted by our ancestors over deep evolutionary time. (more on deep time later) Common misunderstandings about evolutionary psychology (to name but 2) #2 Human behavior is a product of learning, not evolution. This is a false dichotomy. “Learning” and “evolutionary psychology” are not competing explanations, learning requires evolved learning adaptations, at least some of which are specialized for solving distinct adaptive problems. #3 If human behavior is a product of evolved psychological adaptations, it means we cannot change it. This misunderstanding stems from a failure to understand that evolutionary psychology provides a truly interactionist framework. Humans show great flexibility precisely because of the large number of evolved psychological adaptations they possess. Teaching Tools for Evolutionary Psychology The full set of 17 can be found on Dr. Buss’ website www.davidbuss.com A Few Specific Teaching Tools 1) Convey to students an understanding of “Deep Time.” Use a spatial metaphor of a football field. Life first evolved at one end of the field. You would travel a full 99 yards before apes evolved. The genus Homo did not emerge until the last foot of the field. Truly modern humans, Homosapiens (Cro-Magnons) did not colonize Europe until the last tenth of an inch. Teaching Tools #5 Use Sexual Selection Theory to explain the logic of the evolutionary process. The three components of evolution by selection are variation, inheritance and differential reproductive success. Variation (originally caused by mutations) provides the raw materials on which selection operates. Only variants that are inherited, reliably transmitted from parents to offspring, can be selected. Differential reproductive success because of heritable variants is the “bottom line” of evolution by selection. (This is the final arbiter of which characteristics evolve.) Teaching Tools # 7 Hammer home the critical distinction between proximate and ultimate causation. Proximate causation deals with the immediate causes that trigger activation. Ultimate causation deals with the evolution of the mechanism and its adaptive function. Why does Sally develop calluses on her hand? What caused her calluses? (pc) Why did the callus producing mechanism evolve? (uc) Why did Johnny get jealous? Was someone flirting with his girlfriend? (pc) Why have humans evolved the emotion of jealousy? (uc) Teaching Tools #10 Bring in an animal example. Example: Many insects, mammalian and primate species use something called “mate guarding.” Sometimes The male will maintain physical proximity to the mates and conceal them from other males Build a fence Move locations Emit scents that cover the female scent Physically jostle other males away it is easier to see things in other species. Teaching Tools Do humans ever do anything like this? Teaching Tools Do humans ever do anything like this? While each species is unique, humans may use the ability to communicate through language or use some variation in culture to “mate guard.” Ex: Burkas, check-up phone calls, monitoring email or text messages Teaching Tools #12 Use thought experiments. Buss calls this the “mission impossible” exercise. To teach the understanding of the logic of inclusive fitness theory, ask students to consider: “Imagine that you are a gene residing within a body. Your mission is to increase your own replication success (making copies of yourself) relative to competing genes. What would you do?” What would you do? 1) 2) 3) What would you do? 1) Influence the body in which you reside. 2) Ensure that the body in which you reside reproduces. 3) Help other organisms that contain copies of you –genetic relatives- to survive and reproduce. Another example For mating, Buss asks all students to list all of the qualities women want in a long-term mate. List all of the qualities men want in a long-term mate Compare lists. Another example For the topic of conflict, Buss asks all students to make a list of all the things that men they know have done to annoy, irritate, anger or upset women. Make a list of what women do that has the same effect of annoying, irritating, angering or upsetting men. Could this be studied scientifically? To quote Dr. Buss, “Evolutionary psychology has the combination of a powerful big-picture theoretical perspective, real-life applicability and topical intrigue that captures students’ interest.” This is one tough topic to teach!