10/7/14 Outline Nature Vs. Nurture PSC 113 Jeff Schank Emergence and CausaAon •  Emergence and CausaAon •  Nature vs. Nurture: What is Nature? What is Nurture? –  The Program/Blueprint Metaphors –  Developmental Programs –  Causal Loops and Levels of OrganizaAon •  ReducAonism and Holism Flocks of Starlings •  With our modern noAon of Aristotelian causaAon, we can characterize biological and other complex systems in terms of the first three causes 1 10/7/14 Schools of Fish Herds of Mammals Nest ThermoregulaAon in Social Insects Nest ThermoregulaAon in Social Insects FIG. 12 An Apis dorsata [giant honey bees] colony. Workers are spread out on the comb to reduce brood nest temperature (Photo by Ben Oldroyd). Julia C. Jones and Benjamin P. Oldroyd (2007 )Nest ThermoregulaAon in Social Insects.ADVANCES IN INSECT PHYSIOLOGY VOL.33, pp. 153-­‐191) FIG. 10 Apis florea [wild bees] colony (Photo courtesy of Nadine Chapman).
Workers that form the protective curtain covering the comb move closer together
at low ambient temperatures, and further apart at high ambient temperatures.
Julia C. Jones and Benjamin P. Oldroyd (2007)Nest Thermoregulation in Social
Insects. ADVANCES IN INSECT PHYSIOLOGY VOL. 33, pp. 153-191)
2 10/7/14 Nature vs. Nurture: What is Nature? What is Nurture? •  A program is “a series of coded instrucAons which when fed into a computer will automaAcally direct its operaAon in carrying out a specific task”. (A blueprint is plan, scheme, or pagern for something, i.e., Aristotle's formal cause.) Developmental Programs •  Although development does not proceed in a way that is analogous to a computer program, perhaps if we just consider development as a kind of “black box” with the environment providing input •
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Closed programs require no specific input (experience) for development to proceed on its geneAcally predetermined course. Open programs, however, require input or experience in order for developmental program to proceed. Closed Open X CriAcal and SensiAve Periods DisAncAon between CriAcal and SensiAve Periods •  Cri7cal period: A span or period of Ame during which specific environmental input is essenAal if an ability is to develop –  Cri7cal period hypothesis for Language: There is a criAcal period for language acquisiAon that ends with the onset of puberty; if an individual has not received sufficient linguisAc input by then, the individual is incapable of acquiring language •  Sensi7ve period: A span or period of Ame during which specific environmental input is important for the development of an ability, but at least some aspects of that ability can be learned or acquired without receiving the input during a sensiAve period •  Ques7on: is the acquisiAon of language subject to a criAcal period, sensiAve period, or no period at all? Cri7cal X Sensi7ve X X ? 3 10/7/14 TesAng the CriAcal Period Hypothesis for Language •  The problem with the criAcal period hypothesis is that it is not testable in the laboratory •  We cannot take children into a laboratory and raise them with no language input unAl they reach puberty •  However, there have been cases of people who, out of extreme neglect, mistreatment, or unfortunate circumstances, did not receive language input before puberty Genie •  Genie existed for 10 years in a closet Aed to a pogy chair •  She had no discernible linguisAc abiliAes at the Ame she was found (age 13) •  Video Problems •  What other developmental effects did isolaAon have on Genie? •  Was the research adequately conducted? •  Did Genie really fail to acquire syntax and grammar? •  Has there been scienAfic misconduct in the case of Genie? Peter E. Jones •  Concludes that these claims are false or misleading –
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Genie was unable to acquire the morphology of English. Genie was unable to acquire the syntax of English. Genie’s ugerances remained uninflected and telegraphic Genie’s ugerances remained hierarchically flat. Genie’s linguisAc development leveled off during period 1 (1971-­‐1975). 4 10/7/14 Causal Loops and Levels of OrganizaAon Example of Causal Loop (I don’t know if it is accurate) ReducAonism •  Defini7on: ReducAonism is the view that explanaAons of things and/or their behavior should be in terms of things that are simpler, more obvious, and/or more easily understood than the things themselves •  Historical Background –  In the 17th and 18th centuries, the BriAsh philosophers Locke, Berkeley, and Hume, were concerned with how we come to have knowledge of the world and how the mind works –  For all of the them, the mind was essenAally a bundle of ideas –  Twen7eth Century Logical Empiricists: Rudolf Carnap was probably the leading figure of this movement –  The problem concerned the interpretaAon of the things scienAfic theories are about—How can we know a thing in itself? –  Answer: Define all scienAfic terms in terms of statements about observaAons using set theory and logic—It turned out not to be possible 5 10/7/14 ReducAonism •  Historical Background con7nued… –  Behaviorism originated from the complete rejecAon of anthropomorphism, anecdotalism, and introspec7onism at the turn of the century as typified in the behaviorism of J. B. Watson and B. F. Skinner –  Behaviorists start from the proposiAon the behavior of organisms can be studied as natural events and they sought to discover laws of associaAon among behavior and sAmuli resulAng from learning –  Problems: Oversimplified the environment, ignored what happens inside the organism, and ignored social learning and context ReducAonism: Nature vs. Nurture •  Especially in the 20th century to today, many researchers have assumed that the behavior of organisms can be explained by some proporAon of nature (genes) or nurture (environment, experience). •  What proporAon of IQ is determined by genes (nature) and what proporAon by experience (nurture)? •  This quesAon makes it sound as though we can always answer such •  quesAons by giving some percentage such as 60% of IQ is determined by the genes and 40% is determined by experience •  Research in animal behavior has revealed the relaAonship between genes, •  Experience and development are far from this simple (e.g., consider the ring dove reproducAve cycle) •  Thus, the nature vs. nurture disAncAon is reducAonisAc in that it ignores causal loops up and down levels of organizaAon 6