Human Variation, Races, Types, and Ethnic Groups

by Molnar, Stephen

• ISBN13: 9780130336682
• ISBN10: 0130336688
• Edition: 5th
• Format: Paperback
• Copyright: 2002-01-01
• Publisher: Taylor & Francis

Summary

Discarding the concept of race as misleading, this book examines the biological basis for human variation and biological diversity at the population level--appropriate because of the many ways in which humans can adapt to environments, organize activities, and regulate breeding behavior. It reviews the history, behavior, and demographic structure of contemporary populations,and their effects on the distribution of major genetic polymorphisms and distinctions of body form, size, and skin color. Chapter topics include racial variation and the perception of human differences, the biological basis for human variation, traits of simple inheritance, hemoglobin variants and DNA markers, traits of complex inheritance, distribution of human differences, human variability and behavior, and changing dimensions of the human species. For individuals interested in genetic science--and the recent significant achievements in this field.

Table of Contents

Preface	xiii
Racial Variation and the Perception of Human Differences	1	(33)
Human Biological Diversity and the Race Concept: An Introduction	1	(2)
Human Variation: Its Discovery and Classification	3	(5)
Anthropometry: The Measures of Human Variation	8	(7)
Eugenics	15	(2)
Racial Boundaries: Fact or Fiction?	17	(7)
Races, Populations, and Some Causes of Variability	24	(5)
Confusions and Contradictions of Human Classification	29	(5)
The Biological Basis for Human Variation	34	(54)
Principles of Inheritance	35	(12)
Formal Human Genetics	47	(8)
Biological Units: Species, Races, and Populations	55	(1)
Factors of Variation and Evolution	56	(11)
The Gene, DNA, and the ``Code of Life,''	67	(9)
Chromosomes at the Molecular Level	76	(4)
Gene Clusters and Restriction Fragment Length Polymorphisms (RFLP)	80	(3)
Y-Chromosome DNA Polymorphisms	83	(1)
Mitochondrial DNA	84	(2)
Genes and Populations: A Summary	86	(2)
Traits of Simple Inheritance I	88	(49)
Blood Components and Inherited Traits	89	(24)
The Blood Groups: An Overview	113	(1)
White Blood Cell (WBC) (Leukocyte) Antigens	113	(4)
Polymorphisms of Serum Proteins	117	(4)
Inborn Errors of Metabolism	121	(13)
Other Polymorphisms of Anthropological Interest	134	(2)
Traits of Simple Inheritance: Some Conclusions	136	(1)
Traits of Simple Inheritance II: Hemoglobin Variants and DNA Markers	137	(43)
Hemoglobins: Normal and Abnormal	138	(6)
Distribution of Hemoglobin S	144	(4)
Malaria and Natural Selection	148	(3)
Some Other Abnormal Hemoglobins	151	(7)
Distribution of Red-Cell Variants in Sardinian Populations	158	(2)
African Americans and Evidence of Gene Frequency Changes	160	(2)
DNA Markers of Human Variation	162	(15)
Genetic Markers at the DNA Level: Some Conclusions	177	(3)
Traits of Complex Inheritance	180	(59)
Human Form and Its Variability	181	(6)
Head Size and Shape	187	(4)
Face Form	191	(11)
Factors of Growth and Development	202	(19)
The Structure and Function of Skin	221	(5)
Skin Color, Geography, and Natural Selection	226	(8)
Skin Color and Evolution	234	(2)
Eye Color and Hair Color	236	(1)
Hair Form	237	(1)
Some Conclusions	238	(1)
Distribution of Human Differences	239	(32)
Some Factors Contributing to Gene Distribution	241	(3)
Biological Units: Races, Ethnic Groups, or Breeding Populations	244	(9)
Breeding Populations	253	(13)
Clinal Distribution of Traits	266	(2)
Breeding Populations versus Clines: Some Conclusions	268	(3)
Human Variability and Behavior	271	(37)
Race, Ethnic Group, Class, and Behavior	276	(5)
Intelligence Quotient: A Measure of Mental Ability?	281	(13)
Estimates of Inheritance of Mental Ability (IQ)	294	(12)
Genetics, Intelligence, and the Future	306	(2)
Changing Dimensions of the Human Species	308	(46)
Population Growth Rates	309	(2)
Demographic Transitions	311	(6)
Demographic Factors of Population Changes	317	(8)
Health, Disease, and Epidemiological Transition	325	(12)
The Developing World and Epidemiological Transitions	337	(4)
Changing Environments and Natural Selection	341	(3)
Ethnic Groups and Disease	344	(2)
Genetic Counseling and Selective Breeding	346	(2)
Ongoing Evolution and Homo sapiens of the Future	348	(6)
References	354	(17)
Glossary	371	(5)
Index	376

Excerpts

The past four years have been a time of significant achievement for genetic science. Over 90 percent of the DNA of the human genome has been mapped but comprehending the nature of human diversity still presents a problem. The rush to discover genes for various traits of behavior, disease susceptibility, and physical condition has obscured so much about our species. Though the growing body of evidence emphasizes that humans differ in less than one-tenth of 1 percent of their genes, we continue to classify our biological differences in terms of color labels. Much of what I said in the preface to the fourth edition remains relevant today. Antiquated, out-dated race concepts continue to guide both social and medical research. Race, ethnic group, and class are commingled, and the heritability of numerous behavioral attributes is offered as an explanation for major social issues confronting the world today. The mix of biological and social explanations continues despite the advances that have been made in genetic technology. In fact, it is the very growth of knowledge about our genome that has, in some ways, supported a renewed confidence in biological determinism. In this edition, as in previous editions, I shall continue to explore the scope of our knowledge of human diversity and criticize the reliance on racial labels. The mass of new data on genetic markers underscores the weaknesses of these "classic" race divisions. I shall try to guide the reader past the major pitfalls of nineteenth-century thinking as the recent data on "gene geography" and human adaptation are discussed. This edition continues to incorporate the newer records of DNA polymorphisms into a frame of reference that does not depend on race categories. To this end, Chapter 2, "The Biological Basis for Human Variation," has been reorganized and updated with the addition of new genetic data and more population genetic formulas. Chapters 3 and 4 have been revised and expanded, as well, to emphasize the evidence for natural selection inHomo Sapiens.New tables have been added in Chapter 5 to compare the ranges of variation in growth at various ages of children in developed and lesser developed societies. Chapters 6 and 7 have been revised and updated with the addition of new data and arguments over population classification and behavioral diversity. The demographic data from the late 1990s and year 200v have been added to Chapter 8 and show that there is truly a changing dimension to our species diversity. Chapter 1 remains an introductory review of the race concept and, with the addition of the latest census questions regarding race and ethnicity, notes the breadth of the concern for more inclusive classifications. As the analyses of the Census 2000 are reported, some projections note that, in the near future, minorities will no longer be "minorities." This underscores the confusion that has continued from census to census--how should we label each other even when we differ in a few minor ways. As in previous editions, the reviewers' comments, as well as comments from friends and colleagues, are gratefully acknowledged. I would like to thank especially the following individuals who reviewed the manuscript for the fifth edition: James H. Mielke, University of Kansas-Lawrence; David P Tracer, University of Washington; and Trudy Turner, University of Wisconsin-Milwaukee. I would also like to thank the editorial staff of Prentice Hall for their help in guiding this revision through all of the many steps leading to publication. A special acknowledgment for my wife, Iva, who has continued in her support and encouragement, even for this fifth edition. As always, she has been a partner in all phases of the research and writing.