ANTH 1013 1st Edition Lecture 24 Outline of Last Lecture I. DNAII. Behavioral ModernityIII. The peopling of the worldOutline of Current Lecture I. Human racesII. Race and racismIII. How are differences among people distributed?IV. What kind of classification is race?V. EvolutionCurrent LectureI. Human racesi. Modern humans are phenotypically variableii. Are there human races?a. Phenotypic variation around the globe has been/is used to justify the notion that there are human “races”b. Race itself has a particular connotation in biology, so our job for today is to examine the biological validity of human racesc. Many 19th century scientists were interested in phenotypic variation, and devised the sort of racial classification we are familiar withd. These classifications were frequently racist, characterizing different racial groups as more or less “advanced”e. This was eventually fitted into an evolutionary framework, with some races being regarded as “less evolved.” Intelligence, morality, facial shape, etc., all were superior among “Caucasians.”f. Such racist classifications continued into the 20th century1. And are still found in some publicationsg. However one defines it, the act of dividing people into races is an act of classification or placing them into categories1. So why do we classify things?2. To organize and convey informationa. Categories vary with our goalsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.h. What meaning are we conveying when we create groupings of people that we define as races?1. Does the concept of race have any value as a way to describe human biological variation?iii. What classification is race? a. “an arbitrary classification of modern humans, sometimes, especially formerly, based on any or a combination of various physical characteristics, as skin color, facial form, or eye shape, and now frequently based on such genetic markers as blood groups.”b. “a human population partially isolated reproductively from other populations, whose members share a greater degree of physical and genetic similarity with one another than with other humans.”c. “Races are genetically distinct Mendelian populations.”d. “A subspecies (race) is a distinct evolutionary lineage within a species. This definition requires that a subspecies be genetically differentiated due to barriers to genetic exchange that have persisted for long periods of time; that is, the subspecies must have historical continuity in addition to current genetic differentiation.”e. Not biological in nature:1. “any people united by common history, language, cultural traits, etc.”2. “A group of people united or classified together on the basis of common history, nationality, or geographic distribution.”iv. What information do we want to convey?a. Descriptive classification: aims to group items based on observable characteristics1. Unless character states are discrete, there will always be items thatdo not fit available categories2. If you want to describe multiple features, you will need N^2 categories (N = # of described dichotomous featuresb. Most racial categories are defined by a small number of superficial, easily observed characteristics1. The number of racial categories typically used is also small, suggesting that little descriptive information can be conveyed, unless having one characteristic means you also have other characteristicsv. We know some interesting things about geographic variation among humans. For example, skin color variation:a. Darker skin is caused by higher levels of melanin in the cells and is probably an adaptation to high UV radiation.b. Lighter skin has less melanin and is probably an adaptation to low UV radiation, which affects vitamin D productionvi. The problem of items not fitting neatly into categories certainly exists for efforts to classify human populationsa. Characteristics are not clumped into a few ‘races’, but are typically distributed across a cline – a geographical radiation of allele frequencies or phenotypic traitsvii. Gene flowa. The clinal distribution pattern will vary depending on the traitb. Clines crosscut “racial” distinctions1. In part because of gene flow. Alleles are clearly flowing across supposed barriers2. In part because of natural selection. Having one feature clearly does not predict what other feature you will haveviii.Skin color is frequently used to define racial groupsa. Some of the mutations that produce what are defining “racial” characteristics are actually recent mutationsb. One gene that affects human skin pigmentation is known as SLC4A5c. There are only 2 known alleles for this gene in humans and they differ by a single nucleotided. One allele is nearly fixed in Europe and is common all the way east to Pakistan and in northern Africa1. That allele arose 11000 years ago!ix. The categories that we in America use to think about race are largely a product of our colonial history and interaction with people from other regionsa. Further evidence that racial categories are social constructs come from evidence for changes in inclusiveness/exclusivenessb. Other groups define biological distinctions much more differently that we dox. Racial groupings are largely social constructions that have minimal biological reality; what reality they have is largely an artifact of how the category has been constructedII. Race and racismi. Seeing the world (and behaving) in ways that justify hierarchy and inequality among social collectivities identified as ‘races’ii. Assigning (and learning assigned) meanings to perceived differences between groups of peopleiii. Accepting as ‘common sense’ the assumptions and prejudices that characterize racism in everyday lifeiv. What information do we want to conveya. Historical classification: organizes items based on their history, such as their place of originv. Is “race” a historical classification, conveying information about area of origin of human populations? Yes, in part.a. Some facts about historical classifications:1. Assignment to category is unambiguous – things come from somewhere2. Do not carry any descriptive informationvi. People from a particular geographical region will tend to share phenotypic features; however, describing someone as African, for example, tells us only the continent they come from and nothing about