Textbook Notes (368,558)
Canada (161,962)
York University (12,849)
Psychology (3,584)
PSYC 3420 (57)
Chapter 1

Chapter 1 Evolutionary Psychology.docx

9 Pages
Unlock Document

PSYC 3420
Irwin Silverman

Chapter 1 Evolutionary Psychology  Foundations of evolutionary: o Neanderthal man found 50,000 yrs ago, early homicide victim o Fractures and dents more than women; left frontal skull; right handed attacker  Can’t tell us combat was normal or that more aggressive sex o Brain is the most complex; 1,350 cubic cm; new goal of evo Psyc o Focuses on 4 main Q’s: o 1. Why it’s designed the way it is- what caused it to be... o 2. How is human mind designed- mechanism and parts, organization o 3. What are the functions of the component part and structure= whets its purpose o 4. How does input from current environment interact with the design of the human mind to produce observable behaviour?  Ancient Greeks A/P studied the mind; Freud too; skinner  Past few decades to see all disciplines coming together-Psyc, learning, warfare, self-esteem, status, parenting –all under one evolutionary psych  Landmarks in the history of evolutionary thinking: o Evolution before Darwin:  Change over time, change in life forms before by scientists  Jean baptise Pierre Antoine de Monet chevalier de lamark-1744-1829 was one of first to use word biologie thus studying life as a science  Lamarck believed: 1. Progress towards higher form 2. Inheritance of acquired characteristics  Must struggle to survive , enlarging nerve secretion, enlarging organs  Necks of giraffes probably from striving for higher leaves  These were passed down and acquired  Baron gorgers Cuvier 1769-1832- proposed theory catasrophism:  Species are extinguished periodically by catastrophes such as meteors; replaced by other species  Some noted similarities of species to humans; birds to flipper; chimps to us... Page 1 of 9  Change over time seen from fossil records, bones changed, organic structure change  Embryonical development of different species: strikingly similar in species that otherwise seems diff from another  Loop like pattern of arteries- same ancestors milling of yrs ago  All these evidences before 1859 suggested life was changing  Many also saw characteristics for certain species; quills of porcupine help defense; turtle shell,  The mechanisms of change weren’t seen though o Darwin’s theory of natural selection:  Why change takes place, and ways change proceeds; how new emergence, vanishing species...etc...  Darwin took a voyage after Cambridge, on the beagle in 1813 for 5 yrs, to Galapagos islands- found finches-m were all different yet same species  Common ancestor who diverged and local ecological conditions changed their makeup- pivotal to Darwin’s conclusion that species aren’t immutable but change  The existence of adaptations halted him from accepting others ‘explanations  Darwin used Malthus essay on population principle in 1798 to note that: organisms exist in number greater than can survive and reproduce; struggle for existence-favorable variations tend to be preserved; others die out  1. Theory of natural selection and 3 main ingredients  A. Variation b. Inheritance c. Selection  A.Variation:Organisms vary, this is essential for evolution to operate and gives materials to work with evolution  B. Inheritance: passed down reliably parents to offspring; wing deformities by accidents aren’t inherited by offspring-only those variations that are inherited play role in evolutionary process  C. Selection: some heritable variants leave more offspring b.c. they help with survival and reproduction Page 2 of 9  Organisms can live many years and not pass its qualities to future; thus a differential reproductive success- bottom line of evolution by natural selection  Differential-success or failure is defined by success relative to others; more frequent if successful; b.c. survival is key for reproduction o Darwin’s theory of sexual selection:  Survival selection-some things had nothing to do with selection at all;  Plumage of peacock seems to be open invite from predators;  Natural selection focused on adaptation to survival;  Sexual selection focused on adaptations for mating  A.Intrasexual competition: between one sex- outcomes to mates finding o These traits will be passed on ; as female likes it  B.Intersexual selection: preferential mate choice; those who have qualities desired, will mate-those who don’t wont. o Aka- female choice- as they are choosy of mates  Sexual selection succeeded in explaining the anomalies o Role of natural selection and sexual selection in evolutionary theory:  A/B aren’t only causes for evolutionary change  1. Genetic drift-  random changes in population, which come about through  A. Mutation- random hereditary dna changes  B. Founder effect- small portion of population makes a new colony and are not genetically representative of the original population o I.e. more red heds at beg. More red hed later on too  C. Bottle necks- population shrinks due to catastrophes; survivors have only subset of genes of the original population  2. Intention-  Not intentional and cannot look into future; maybe giraffes long necks will suck in 20 yrs, but now it’s good for those leaves  3. Gradual- Page 3 of 9  Dozens of millions of generations for process to shape as we see today; some slow, other more rapid  Sudden changes-punctuated equilibrium o Tiny increments in each generation , and take thousands of yrs  Darwin’s theory explained new species, although not b.c. of geographic isolation  Accounted for the modification of organic structures over time  Apparent purposeful design linked to survival and reproduction  He went through one grand tree of descent ; connected with others  Share common ancestry to chimps 98%  Many human genes have counterpart genes in caenorhabditis elegans- chemical structure that humans evolved from one ancestor  Caused controversy, scepticism, lacked coherent theory of inheritance,  Lacked solid basis for heredity  How could partial wings help birds, - all must be advantageous; yet partial forms can be adaptive even before they evolve  His wife was deeply religious; so he waited for the publications  What was not known in his day makes it more important to elaborate on now o Modern synthesis genes and particulate inheritance:  Mechanism of inherence not known then; mendle shows it is particulate and not blended  Passed in intact packets called genes; can’t be acquired  Gene- defined as smallest discrete unit inherited by offspring’s intact, w/e being broken up or blended  Genotypes-entire collection of genes within an individual; not passed down intact in contrast  Genotypes with sexual reproduction is broken up each generation; each person inherits a random half of genes from mothers genotype and random from fathers genotype  Specific half of genes we inherit from each parent-are identical to half of those possessed by that parent; b.c. they are discrete without modification Page 4 of 9  Modern synthesis movement in 30-40’s- discarded biological misconceptions such as lamaracks o Ethology movement:  Behaviour leaves no fossils  All behaviou
More Less

Related notes for PSYC 3420

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.