AA> Vol.4 No.2, May 2014

The Puzzle of European Hair, Eye, and Skin Color

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ABSTRACT

Europeans, particularly northern and eastern Europeans, are unusually colored. Their hair can be not only black but also brown, flaxen, golden, or red, and their eyes not only brown but also blue, gray, hazel, or green. Their skin is pale, almost like an albino’s. This color scheme is more developed in women than in men and seems to have been selected for its visual properties, particularly brightness and novelty. Sexual selection is a likely cause. It favors eye-catching colors and, if strong enough, can produce a color polymorphism, i.e., whenever a visible feature becomes differently colored through mutation, the new color will spread through the population until it loses its novelty value and becomes as frequent as the original one. Such selection is consistent with 1) the many alleles for European hair and eye color; 2) the high ratio of nonsynonymous to synonymous variants; and 3) the relatively short time over which this color diversity developed. Sexual selection will target women if they outnumber men on the mate market. Among early modern humans, such imbalances resulted from 1) a low polygyny rate (because few men could provide for a second wife and her children) and 2) a high risk of early male death (because long hunting distances increased exposure to environmental hazards). Sexual selection of women was stronger at latitudes farther from the equator, where men were less polygynous and more at risk of death while hunting. It was strongest on continental steppe-tundra, where men provided for almost all family food needs by pursuing herds of reindeer and other herbivores over long distances. Although this type of environment is now fragmentary, it covered until 10,000 years ago a much larger territory—the same area where, today, hair and eyes are diversely colored and skin almost milk white.

Cite this paper

Frost, P. (2014). The Puzzle of European Hair, Eye, and Skin Color. Advances in Anthropology, 4, 78-88. doi: 10.4236/aa.2014.42011.

References

[1] Anderson, W. W. (1969). Polymorphism Resulting from the Mating Advantage of Rare Male Genotypes. Proceedings of the National Academy of Sciences USA, 64, 190-197.
http://dx.doi.org/10.1073/pnas.64.1.190
[2] Anon (2008). Maxim’s Audience Prefers Brunettes; Distribution Is Bimodal. Gene Expression, July 6.
http://www.gnxp.com/blog/2008/07/maxims-audience-prefers-brunettes.php
[3] Beleza, S., Murias dos Santos, A., McEvoy, B., Alves, I., Martinho, C., Cameron, E., Shriver, M. D., Parra, E. J., & Rocha, J. (2013). The Timing of Pigmentation Lightening in Europeans. Molecular Biology and Evolution, 30, 24-35.
http://dx.doi.org/10.1093/molbev/mss207
[4] Box, N. F., Wyeth, J. R., O’Gorman, L. E., Martin, N. G., & Sturm, R. A. (1997). Characterization of Melanocyte Stimulating Hormone Receptor Variant Alleles in Twins with Red Hair. Human Molecular Genetics, 6, 1891-1897.
http://dx.doi.org/10.1093/hmg/6.11.1891
[5] Branicki, W., Brudnik, U., & Wojas-Pelc, A. (2009). Interactions between HERC2, OCA2 and MC1R May Influence Human Pigmentation Phenotype. Annals of Human Genetics, 73, 160-170.
http://dx.doi.org/10.1111/j.1469-1809.2009.00504.x
[6] Brockmole, J. R., & Boot, W. R. (2009). Should I Stay or Should I Go? Attentional Disengagement from Visually Unique and Unexpected Items at Fixation. Journal of Experimental Psychology: Human Perception, 35, 808-815.
[7] Brooks, R. (2002).Variation in Female Mate Choice within Guppy Populations: Population Divergence, Multiple Ornaments and the Maintenance of Polymorphism. Genetica, 116, 343-358.
http://dx.doi.org/10.1023/A:1021228308636
[8] Burch Jr., E. S. (1972). The Caribou/Wild Reindeer as a Human Resource. American Antiquity, 37, 339-368.
http://dx.doi.org/10.2307/278435
[9] Butzer, K. W. (1971). Environment and Archeology. Aldine: Chicago.
[10] Canfield, V. A., Berg, A., Peckins, S., Wentzel, S. M., Ang, K. C., Oppenheimer, S., & Cheng, K. C. (2014). Molecular Phylogeography of a Human Autosomal Skin Color Locus under Natural Selection. G3, 3, 2059-2067.
[11] Choi, S. C., & Trotter, M. A. (1970). Statistical Study of the Multivariate Structure and Race-Sex Differences of American White and Negro Fetal Skeletons. American Journal of Physical Anthropology, 33, 307-312.
http://dx.doi.org/10.1002/ajpa.1330330304
[12] Coplan, R., Coleman, B., & Rubin, K. (1998). Shyness and Little Boy Blue: Iris Pigmentation, Gender, and Social Wariness in Preschoolers. Developmental Psychobiology, 32, 37-44.
http://dx.doi.org/10.1002/(SICI)1098-2302(199801)32:1<37::AID-DEV4>3.0.CO;2-U
[13] Darwin, C. (1936 [1888]). The Descent of Man and Selection in Relation to Sex (2nd ed.). New York: Random House.
[14] Duffy, D. L., Box, N. F., Chen, W., Palmer, J. S., Montgomery, G. W., James, M. R., Hayward, N. K., Martin, N. G., & Sturm, R. A. (2004). Interactive Effects of MC1R and OCA2 on Melanoma Risk Phenotypes. Human Molecular Genetics, 13, 447-461.
http://dx.doi.org/10.1093/hmg/ddh043
[15] Duffy, D. L., Montgomery, G. W., Chen, W., Zhao, Z. Z., Le, L., James, M. R., Hayward, N. K., Martin, N. G., & Sturm, R. A. (2007). A Three-Single-Nucleotide Polymorphism Haplotype in Intron 1 of OCA2 Explains Most Human Eye-Color Variation. American Journal of Human Genetics, 80, 241-252.
http://dx.doi.org/10.1086/510885
[16] Dupuis-Roy, N., Fortin, I., Fiset, D., & Gosselin, F. (2009). Uncovering Gender Discrimination Cues in a Realistic Setting. Journal of Vision, 9, 10.1-10.8.
[17] Eakley, A. L., & Houde, A. E. (2004). Possible Role of Female Discrimination against “Redundant” Males in the Evolution of Colour Pattern Polymorphism in Guppies. Proceedings of the Royal Society of London B: Biological Sciences, 271, S299-S301.
http://dx.doi.org/10.1098/rsbl.2004.0165
[18] Edwards, E. A., & Duntley, S. Q. (1939). The Pigments and Color of Living Human Skin. American Journal of Anatomy, 65, 1-33.
http://dx.doi.org/10.1002/aja.1000650102
[19] Edwards, E. A., & Duntley, S. Q. (1949). Cutaneous Vascular Changes in Women in Reference to the Menstrual Cycle and Ovariectomy. American Journal of Obstetrics & Gynecology, 57, 501-509.
[20] Edwards, E. A., Hamilton, J. B., Duntley, S. Q., & Hubert, G. (1941). Cutaneous Vascular and Pigmentary Changes in Castrate and Eunuchoid Men. Endocrinology, 28, 119-128.
http://dx.doi.org/10.1210/endo-28-1-119
[21] Eiberg, H., Troelsen, J., Nielsen, M., Mikkelsen, A., Mengel-From, J., Kjaer, K. W., & Hansen, L. (2008). Blue Eye Color in Humans May Be Caused by a Perfectly Associated Founder Mutation in a Regulatory Element Located within the HERC2 Gene Inhibiting OCA2 Expression. Human Genetics, 123, 177-187.
http://dx.doi.org/10.1007/s00439-007-0460-x
[22] Emlen, S. T., & Oring, L. W. (1977). Ecology, Sexual Selection, and the Evolution of Mating Systems. Science, 197, 215-223.
http://dx.doi.org/10.1126/science.327542
[23] Endler, J. A. (1980). Natural Selection on Color Patterns in Poecilia reticulata. Evolution, 34, 76-91.
http://dx.doi.org/10.2307/2408316
[24] Farr, J. A. (1980). Social Behavior Patterns as Determinants of Reproductive Success in the Guppy Poecilia reticulata Peters (Pisces: Poeciliidae). Behaviour, 74, 38-90.
http://dx.doi.org/10.1163/156853980X00311
[25] Flanagan, N., Healy, E., Ray, A., Philips, S., Todd, C., Jackson, I. J., Birch-Machin, M. A., & Rees, J. L. (2000). Pleiotropic Effects of the Melanocortin 1 Receptor (MC1R) Gene on Human Pigmentation. Human Molecular Genetics, 9, 2531-2537.
http://dx.doi.org/10.1093/hmg/9.17.2531
[26] Frost, P. (1988). Human Skin Color: A Possible Relationship between Its Sexual Dimorphism and Its Social Perception. Perspectives in Biology and Medicine, 32, 38-58.
[27] Frost, P. (2006). European Hair and Eye Color—A Case of Frequency-Dependent Sexual Selection? Evolution and Human Behavior, 27, 85-103.
http://dx.doi.org/10.1016/j.evolhumbehav.2005.07.002
[28] Frost, P. (2007). Comment on Human Skin-Color Sexual Dimorphism: A Test of the Sexual Selection Hypothesis. American Journal of Physical Anthropology, 133, 779-781.
http://dx.doi.org/10.1002/ajpa.20555
[29] Frost, P. (2008). Sexual Selection and Human Geographic Variation, Special Issue: Proceedings of the 2nd Annual Meeting of the North-Eastern Evolutionary Psychology Society. Journal of Social, Evolutionary, and Cultural Psychology, 2, 169-191.
http://dx.doi.org/10.1037/h0099346
[30] Frost, P. (2010). Femmes claires, hommes fonces. Les racines oubliees du colorisme (202 p). Quebec City: Les Presses de l’Universite Laval.
[31] Gasperino, J. (1996). Ethnic Differences in Body Composition and Their Relation to Health and Disease in Women. Ethnicity & Health, 1, 337-347.
http://dx.doi.org/10.1080/13557858.1996.9961803
[32] Gibbons, A. (2007). American Association of Physical Anthropologists Meeting: European Skin Turned Pale Only Recently, Gene Suggests. Science, 316, 364.
[33] Goebel, T. (1999). Pleistocene Human Colonization of Siberia and Peopling of the Americas: An Ecological Approach. Evolutionary Anthropology, 8, 208-227.
http://dx.doi.org/10.1002/(SICI)1520-6505(1999)8:6<208::AID-EVAN2>3.0.CO;2-M
[34] Graf, K. E. (2009a). “The Good, the Bad, and the Ugly”: Evaluating the Radiocarbon Chronology of the Middle and Late Upper Paleolithic in the Enisei River Valley, South-Central Siberia. Journal of Archaeological Science, 36, 694-707.
http://dx.doi.org/10.1016/j.jas.2008.10.014
[35] Graf, K. E. (2009b). Modern Human Colonization of the Siberian Mammoth Steppe: A View from South-Central Siberia. In M. Camps, & P. Chauhan (Eds.), Sourcebook of Paleolithic Transitions (pp. 484-496). Berlin: Springer Science & Business Media.
http://dx.doi.org/10.1007/978-0-387-76487-0_32
[36] Grant, B., Snyder, A., & Glessner, S. F. (1974). Frequency-Dependent Mate Selection in Mormoniella vitripennis. Evolution, 28, 259-264.
http://dx.doi.org/10.2307/2407327
[37] Hampton, K. J., Hughes, K. A., & Houde, A. E. (2009). The Allure of the Distinctive: Reduced Sexual Responsiveness of Female Guppies to “Redundant” Male Colour Patterns. Ethology, 115, 475-481.
http://dx.doi.org/10.1111/j.1439-0310.2009.01634.x
[38] Harding, R. M., Healy, E., Ray, A. J., Ellis, N. S., Flanagan, N., Todd, C., Dixon, C., Sajantila, A., Jackson, I. J., Birch-Machin, M. A., & Rees, J. L. (2000). Evidence for Variable Selective Pressures at MC1R. American Journal of Human Genetics, 66, 1351-1361.
http://dx.doi.org/10.1086/302863
[39] Healey, M., Uller, T., & Olsson, M. (2008). Variety Is the Spice of Life: Female Lizards Choose to Associate with Colour-Polymorphic Male Dyads. Ethology, 114, 231-237.
http://dx.doi.org/10.1111/j.1439-0310.2007.01469.x
[40] Hoffecker, J. F. (2002). Desolate Landscapes. Ice-Age Settlement in Eastern Europe. New Brunswick: Rutgers University Press.
[41] Hrdlicka, A. (1898). Physical Differences between White and Colored Children. American Anthropologist, 11, 347-350.
http://dx.doi.org/10.1525/aa.1898.11.11.02a00020
[42] Hughes, K. A., Du, L., Rodd, F. H., & Reznick, D. N. (1999). Familiarity Leads to Female Mate Preference for Novel Males in the Guppy, Poecilia reticulata. Animal Behavior, 58, 907-916.
http://dx.doi.org/10.1006/anbe.1999.1225
[43] Hughes, K. A., Rodd, F. H., & Reznick, D. N. (2005). Genetic and Environmental Effects on Secondary Sex Traits in Guppies (Poecilia reticulata). Journal of Evolutionary Biology, 18, 35-45.
http://dx.doi.org/10.1111/j.1420-9101.2004.00806.x
[44] Jablonski, N. G., & Chaplin, G. (2000). The Evolution of Human Skin Coloration. Journal of Human Evolution, 39, 57-106 (p. 71, 76).
[45] Kayser, M., Liu, F., Janssens, A. C. J. W., Rivadeneira, F., Lao, O., van Duijn, K., Vermeulen, M., Arp, P., Jhamai, M. M., van Ijcken, W. F. J., den Dunnen, J. T., Heath, S., Zelenika, D., Despriet, D. D. G., Klaver, C. C. W., Vingerling, J. R., de Jong, P. T. V. M., Hofman, A., Aulchenko, Y. S., Uitterlinden, A. G., Oostra, B. A., & van Duijn, C. M. (2008). Three Genome-Wide Association Studies and a Linkage Analysis Identify HERC2 as a Human Iris Color Gene. American Journal of Human Genetics, 82, 411-423.
http://dx.doi.org/10.1016/j.ajhg.2007.10.003
[46] Kelly, R. L. (1995). The Foraging Spectrum. Diversity in Hunter-Gatherer Lifeways. Washington DC: Smithsonian Institution Press.
[47] Kjellstrom, R. (1973). Eskimo Marriage. An Account of Traditional Eskimo Courtship and Marriage (p. 80). Lund: Nordiska Museets Handlingar.
[48] Kleisner, K., Kocnar, T., Rubesova, A., & Flegr, J. (2010). Eye Color Predicts but Does Not Directly Influence Perceived Dominance in Men. Personality and Individual Differences, 49, 59-64.
http://dx.doi.org/10.1016/j.paid.2010.03.011
[49] Kleisner, K., Priplatova, L., Frost, P., & Flegr, J. (2013). Trustworthy-Looking Face Meets Brown Eyes. PLoS ONE, 8, e53285.
http://dx.doi.org/10.1371/journal.pone.0053285
[50] Kokko, H., Jennions, M. D., & Houde, A. (2007). Evolution of Frequency-Dependent Mate Choice: Keeping Up with Fashion Trends. Proceedings of the Royal Society of London B: Biological Sciences, 274, 1317-1324.
http://dx.doi.org/10.1098/rspb.2007.0043
[51] Krupnik, I. I. (1985). The Male-Female Ratio in Certain Traditional Populations of the Siberian Arctic. Inuit Studies, 9, 115-140.
[52] Lazaridis, I., Patterson, N., Mittnik, A., Renaud, G., Mallick, S. et al. (2013). Ancient Human Genomes Suggest Three Ancestral Populations for Present-Day Europeans. BioRxiv, December 23.
http://biorxiv.org/content/early/2013/12/23/001552.full-text.pdf+html
[53] Lea-Greenwood, G. (1998). Visual Merchandising: A Neglected Area in UK Fashion Marketing? International Journal of Retail & Distribution Management, 26, 324-329.
http://dx.doi.org/10.1108/09590559810231797
[54] Liberton, D. K., Matthes, K. A., Pereira, R., Frudakis, T., Puts, D. A., & Shriver, M. D. (2009). Patterns of Correlation between Genetic Ancestry and Facial Features Suggest Selection on Females Is Driving Differentiation, Abstract #668W. American Society of Human Genetics, 59th Annual Meeting, Honolulu, 20-24 October 2009.
[55] Liu, F., Wollstein, A., Hysi, P. G., Ankra-Badu, G. A., Spector, T. D., Park, D., Zhu, G., Larsson, M., Duffy, D. L., Montgomery, G. W., Mackey, D. A., Walsh, S., Lao, O., Hofman, A., Rivadeneira, F., Vingerling, J. R., Uitterlinden, A. G., Martin, N. G., Hammond, C. J., & Kayser, M. (2010). Digital Quantification of Human Eye Color Highlights Genetic Association of Three New Loci. PLoS Genetics, 6, e1000934.
http://dx.doi.org/10.1371/journal.pgen.1000934
[56] Maan, M. E., & Cummings, M. E. (2009). Sexual Dimorphism and Directional Sexual Selection on Aposematic Signals in a Poison Frog. Proceedings of the National Academy of Sciences of the United States of America, 106, 19072-10977.
http://dx.doi.org/10.1073/pnas.0903327106
[57] Maanasa, R., Skoglund, P., Graf, K. E., Metspalu, M., Albrechtsen, A., Moltke, I., Rasmussen, S., Stafford Jr., T. W., Orlando, L., Metspalu, E., Karmin, M., Tambets, K., Roots, S., Magi, R., Campos, P. F., Balanovska, E., Balanovsky, O., Khusnutdinova, E., Litvinov, S., Osipova, L. P., Fedorova, S. A., Voevoda, M. I., DeGiorgio, M., Sicheritz-Ponten, T., Brunak, S., Demeshchenko, S., Kivisild, T., Villems, R., Nielsen, R., Jakobsson, M., & Willerslev, E. (2013). Upper Palaeolithic Siberian Genome Reveals Dual Ancestry of Native Americans. Nature, published online 20 November 2013.
[58] Madrigal, L., & Kelly, W. (2006). Human Skin-Color Sexual Dimorphism: A Test of the Sexual Selection Hypothesis. American Journal of Physical Anthropology, 132, 470-482.
http://dx.doi.org/10.1002/ajpa.20453
[59] Makova, K., & Norton, H. (2005). Worldwide Polymorphism at the MC1R Locus and Normal Pigmentation Variation in Humans. Peptides, 26, 1901-1908.
http://dx.doi.org/10.1016/j.peptides.2004.12.032
[60] Manning, A. (1972). An Introduction to Animal Behaviour (2nd ed.). London: Edward Arnold.
[61] Manning, J. T., Bundred, P. E., & Mather, F. M. (2004). Second to Fourth Digit Ratio, Sexual Selection, and Skin Colour. Evolution and Human Behavior, 25, 38-50.
http://dx.doi.org/10.1016/S1090-5138(03)00082-5
[62] Martin, M. K. (1974). The Foraging Adaptation—Uniformity or Diversity? In Addison-Wesley Module in Anthropology, Issue 56, Boston, MA: Addison-Wesley.
[63] Martinez-Cadenas, C., Pena-Chilet, M., Ibarrola-Villava, M., & Ribas, G. (2013). Gender Is a Major Factor Explaining Discrepancies in Eye Colour Prediction Based on HERC2/OCA2 Genotype and the IrisPlex Model. Forensic Science International: Genetics, 7, 453-460.
http://dx.doi.org/10.1016/j.fsigen.2013.03.007
[64] Mather, F., Manning, J. T., & Bundred, P. E. (unpublished) 2nd to 4th Digit Ratio, Hair and Eye Colour in Caucasians: Evidence for Blond Hair as a Correlate of High Prenatal Oestrogen.
[65] Mazess, R. B. (1967). Skin Color in Bahamian Negroes. Human Biology, 39, 145-154.
[66] Meredith, H. V., & Spurgeon, J. H. (1980). Somatic Comparisons at Age 9 Years for South Carolina White Girls and Girls of Other Ethnic Groups. Human Biology, 52, 401-411.
[67] Muggleton, J. (1979). Non-Random Mating in Wild Populations of Polymorphic Adalia Bipunctata. Heredity, 42, 57-65.
http://dx.doi.org/10.1038/hdy.1979.6
[68] Nelson, J. K., & Nelson, K. R. (1986). Skinfold Profiles of Black and White Boys and Girls Ages 11 - 13. Human Biology, 58, 379-390.
[69] Norton, H. L., & Hammer, M. F. (2007). Sequence Variation in the Pigmentation Candidate Gene SLC24A5 and Evidence for Independent Evolution of Light Skin in European and East Asian Populations. Program of the 77th Annual Meeting of the American Association of Physical Anthropologists, 179.
[70] Oakley, M. (ed.) (1990). Design Management. A Handbook of Issues and Methods. Oxford: Basil Blackwell.
[71] Olalde, I., Allentoft, M. E., Sanchez-Quinto, F., Saintpere, G., Chiang, C. W. K. et al. (2014). Derived Immune and Ancestral Pigmentation Alleles in a 7000-Year-Old Mesolithic European. Nature, early view.
[72] Olendorf, R., Rodd, F. H., Punzalan, D., Houde, A. E., Hurt, C., Reznick, D. N., & Hughes, K. A. (2006). Frequency-Dependent Survival in Natural Guppy Populations. Nature, 44, 633-636.
http://dx.doi.org/10.1038/nature04646
[73] Olivier, G. (1960). Pratique Anthropologique. Paris: Vigot Freres.
[74] Rana, B. K., Hewett-Emmett, D., Jin, L., Chang, B. H. J., Sambuughin, N., Lin, M., Watkins, S., Bamshad, M., Jorde, L. B., Ramsay, M., Jenkins, T., & Li, W. H. (1999). High Polymorphism at the Human Melanocortin 1 Receptor Locus. Genetics, 151, 1547-1557.
[75] Ray, N., & Adams, J. M. (2001). A GIS-Based Vegetation Map of the World at the Last Glacial Maximum (25,000-15,000 BP)-(23rd Millennium to 13th Millennium BC). Internet Archaeology, 11.
http://dx.doi.org/10.11141/ia.11.2
[76] Robins, A. H. (1991). Biological Perspectives on Human Pigmentation. Cambridge: Cambridge University Press.
http://dx.doi.org/10.1017/CBO9780511600463
[77] Russell, R. (2009). A Sex Difference in Facial Pigmentation and Its Exaggeration by Cosmetics. Perception, 38, 1211-1219.
http://dx.doi.org/10.1068/p6331
[78] Russell, R. (2010). Why Cosmetics Work. In R. Adams, N. Ambady, K. Nakayama, & S. Shimojo (Eds.), The Science of Social Vision (pp. 186-203). New York: Oxford.
http://dx.doi.org/10.1093/acprof:oso/9780195333176.003.0011
[79] Schild, R. (1976). The Final Paleolithic Settlements of the European Plain. Scientific American, 234, 88-99.
http://dx.doi.org/10.1038/scientificamerican0276-88
[80] Shekar, S. N., Duffy, D. L., Frudakis, T., Montgomery, G. W., James, M. R., Sturm, R. A., & Martin, N. G. (2008). Spectrophotometric Methods for Quantifying Pigmentation in Human Hair-Influence of MC1R Genotype and Environment. Photochemistry and Photobiology, 84, 719-726.
http://dx.doi.org/10.1111/j.1751-1097.2007.00237.x
[81] Simchuk, A. P. (2001). Frequency-Dependent Sexual Selection in a Natural Population of Oak Leafroller Moth (Tortrix viridana L.). Tsitologiya i Genetika, 35, 25-29.
[82] Sinnock, P. (1970). Frequency Dependence and Mating Behavior in Tribolium castaneum. The American Naturalist, 104, 469-476.
http://dx.doi.org/10.1086/282681
[83] Soejima, M., Tachida, H., Ishida, T., Sano, A., & Koda, Y. (2005). Evidence for Recent Positive Selection at the Human AIM1 Locus in a European Population. Molecular Biology & Evolution, 23, 179-188.
http://dx.doi.org/10.1093/molbev/msj018
[84] Stansfield, J., & Whitfield, T. W. A. (2005) Can Future Colour Trends Be Predicted on the Basis of Past Colour Trends? An Empirical Investigation. Color Research & Application, 30, 235-242.
http://dx.doi.org/10.1002/col.20110
[85] Steggerda, M. (1941). Change in Hair Color with Age. Journal of Heredity, 32, 402-403.
[86] Sturm, R. A., & Frudakis, T. N. (2004). Eye Colour: Portals into Pigmentation Genes and Ancestry. Trends in Genetics, 20, 327-332.
http://dx.doi.org/10.1016/j.tig.2004.06.010
[87] Sturm, R. A., Duffy, D. L., Zhao, Z. Z., Leite, F. P. N., Stark, M. S., Hayward, N. K., Martin, N. G., & Montgomery, G. W. (2008). A Single SNP in an Evolutionary Conserved Region within Intron 86 of the HERC2 Gene Determines Human Blue-Brown Eye Color. American Journal of Human Genetics, 82, 424-431.
http://dx.doi.org/10.1016/j.ajhg.2007.11.005
[88] Tarr, M. J., Kersten, D., Cheng, Y., & Rossion, B. (2001). It’s Pat! Sexing Faces Using Only Red and Green. Journal of Vision, 1, 337.
[89] Templeton, A. R. (2002). Out of Africa Again and Again. Nature, 416, 45-51.
http://dx.doi.org/10.1038/416045a
[90] Thelen, T. H. (1983). Minority type Human Mate Preference. Social Biology, 30, 162-180.
[91] van den Berghe, P. L. (1979). Human Family Systems. An Evolutionary View. New York: Elsevier.
[92] van den Berghe, P. L., & Frost, P. (1986). Skin Color Preference, Sexual Dimorphism and Sexual Selection: A Case of Gene-Culture Co-Evolution? Ethnic and Racial Studies, 9, 87-113.
http://dx.doi.org/10.1080/01419870.1986.9993516
[93] Voight, B. F., Kudaravalli, S., Wen, X., & Pritchard, J. K. (2006). A Map of Recent Positive Selection in the Human Genome. PLoS Biology, 4, e72.
http://dx.doi.org/10.1371/journal.pbio.0040072

  
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