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This is the first of a series of three articles on IQ, heredity, & equality. Focus here is on A. Jensen's hypothesis (Educability and Group Differences, New York: Harper & Row, 1973) that the mean IQ short-fall for blacks is genetically caused. Consideration is given to the theoretical & logical structure of the argument that intergroup variations in average IQ are primarily influenced by heredity. Original data from heritability studies involving separated identical twins are untrustworthy, besides which, such statistics apply only to specific breeding & rearing populations, & they cannot be generalized to other populations. The heritability of a trait may be nothing more than a function of the extent to which salient features of the environments in which the observed population lives are themselves alike or unlike. Within-group variance cannot be generalized to account for between-group differences. Ss of twin studies involve much less group-environment conflict than is true for black people in largely white America. No plausible historical or anthropological account has been offered as to why ex-Africans in America should have disfavored genes for intelligence. The heritability of the intelligence-as-measured-by-IQ is irrelevant to questions of causation & prognosis; that kind of intelligence is a malleable trait. If inheritance is discounted as a major cause of between-group differentials in IQ, it is not difficult to find aspects of environment that can reasonably & clearly be expected to have had a striking differential impact on the IQ performances of the races in the US. Jensen's "genetic hypothesis" is not only illogically applied to interracial comparisons, it is unnecessary & misconceived for explaining the racial IQ gap. AA.

Ninety-four identical twins, 124 fraternal twins, 470 brothers (reared together) and 2973 unrelated boys, all in the 12–18 age range were measured on three personality scales – namely ego strength. C, super ego strength, G, and self-sentiment strength, Q3 - adding both forms
of the High School Personality Questionnaire (HSPQ). Age corrections brought brothers 'scores to equivalence at the same age, and intra-pair and inter family concrete variances were calculated on that basis.

The criticisms of P. Green regarding IQ (see SA 26:2/J2506; 'The Pseudoscience of Arthur Jensen,' Dissent, 1976, summer; 'IQ and the Future of Equality,' Dissent, 1976, fall) derive from a confusion of socialism, or public ownership of the means of production, with egalitarianism. Helping the mentally disadvantaged is a desirable goal, but not attainable when reformers refuse to recognize their existence. Whether IQ is due to heredity or environment, it remains socially important as a predictor of occupational status; & evidence for its heritability is good. In The IQ Controversy: Myths of Hereditarianism, Philip Green (Smith college, Northampton, Mass) notes that differences in social status in the market are not due to agreement among people, but to the operation of political & market power held by institutions. Further, Herrnstein's discussion of heritability fails to provide any scientific justification for this concept's application to intelligence. Actual knowledge of how industries work shows that pay & productivity are not particularly closely related in any case. The intellectual deficits that Herrnstein notes are produced by specific social conditions which need to be changed. W. H. Stoddard.

1. The genetical foundation -- 1. Continuous variation -- 2. The genic basis -- 3. Assaying the chromosomes -- 4. Locating the genes -- 2. The biometrical approach -- 5. The manifestation of polygenic systems -- 6. Genetic analysis and somatic analysis -- 7. Biometrical genetics -- 3. Additive and dominance effects -- 8. Components of means -- 9. Testing the model -- 10. Scales -- 11. Components of variation: F2 and back-crosses -- 12. Generations derived from F2 -- 13. The balance sheet of genetic variability -- 14. Partitioning the variation -- 4. Diallels -- 15. The principles of diallel analysis -- 16. An example of a simple diallel -- 17. Undefined diallels -- 18. An example of an undefined diallel -- 5. Genic interaction and linkage -- 19. Non-allelic interaction -- 20. Interaction as displayed by means -- 21. Variances and covariances -- 22. Correlated gene distributions: linkage -- 23. Diallels -- 6. Interaction of genotype and environment -- 24. Genotype x environment interaction -- 25. Two genotypes and two environments -- 26. A more complex case -- 27. The relation of g to e -- 28. Crosses between inbred lines -- 29. Variance of F2 -- 7. Randomly breeding populations -- 30. The components of variation -- 31. Human populations -- 32. The use of twins -- 33. Experimental analysis -- 34. Complicating factors -- 35. Heritability -- 8. Genes and effective factors -- 36. Estimating the number of segregating genes -- 37. Consequences of linkage: effective factors -- 38. Other sources of estimates -- 9. Conclusion -- 39. Designing the experiments -- 40. Concepts and uses -- Glossary of symbols and abbreviations -- References.

1 Plant Breeders and Their Work -- What Is Plant Breeding? -- The Strategy of Plant Breeding -- Training for the Modern Plant Breeder -- Some Early Plant Breeders -- Some Accomplishments in Plant Breeding -- Who Does Plant Breeding in the United States? -- 2 Reproduction in Crop Plants -- Types of Reproduction -- Sexual Reproduction in Crop Plants -- Asexual Reproduction in Crop Plants -- 3 Gene Recombination in Plant Breeding -- Variation, the Basis of Plant Breeding -- The Mechanism of Mendelian Heredity -- Gene Recombination Following Hybridization -- Gene Structure and Action -- 4 Quantitative Inheritance in Plant Breeding -- Quantitative Inheritance and its Measurement -- Multiple Alleles -- Types of Gene Action -- Heritability -- Selection Intensity and Genetic Advance -- Gene Frequency and Genetic Equilibrium -- Gene Recombination and Plant Breeding -- 5 Variations in Chromosome Number -- Polyploidy -- Aneuploidy -- Haploidy -- 6 Mutation -- The Nature of Mutation -- Induction of Mutation -- Mutator Genes and Controlling Elements -- Some Mutation-Breeding Experiments -- Role of Mutation Breeding -- 7 Fertility-Regulating Mechanisms and Their Manipulation -- Incompatibility -- Male Sterility -- Apomixis -- Interspecific Hybridization -- 8 Plant Cell and Tissue Culture: Applications in Plant Breeding -- Plant Cell and Tissue Culture -- Clonal Propagation -- Embryo Culture, Ovule Culture, and in Vitro Pollination -- Anther Culture and Haploid Plant Production -- Genetic Variability from Cell Cultures -- Somatic Cell Hybridization -- Plant Genetic Engineering -- 9 Germplasm Resources and Conservation -- Germplasm Conservation -- Germplasm Resources and Their Maintenance in the United States -- How Genetic Resources Are Utilized -- Acclimatization -- 10 Breeding Self-Pollinated Crops -- What Is a Variety? -- Genetic Significance of Pollination Method -- Breeding Methods in Self-Pollinated Crops -- Plant Breeding: A Numbers Game? -- 11 Breeding Cross-Pollinated and Clonally Propagated Crops -- Genetic Structure of Cross-Pollinated Crops -- Breeding Seed-Propagated Cross-Pollinated Crops -- Breeding Clonally Propagated Crops -- 12 Breeding Hybrids -- Proprietary Nature of Hybrid Varieties -- Inbreeding -- Hybrid Vigor or Heterosis -- Double-Cross Hybrid Corn—The Model for Hybrid Breeding -- Cytoplasmic Male Sterility and Hybrid Seed Production -- Alternative Hybrid Procedures -- 13 Techniques in Breeding Field Crops -- Selfing and Crossing -- Conducting Field Trials -- Maturity Comparisons -- Resistance to Lodging and Shattering -- Resistance to Stress -- Breeding for Disease Resistance -- Breeding for Insect Resistance -- Measuring Quality -- Keeping Accurate Records -- 14 Breeding Wheat and Triticale -- Breeding Wheat -- Breeding Triticale -- 15 Breeding Rice -- Origin and Types -- Varieties -- Botany and Genetics -- Breeding Methods -- Breeding Objectives -- Upland Rice -- Deep-Water and Floating Rice -- Wild Rice -- 16 Breeding Barley and Oats -- Breeding Barley -- Breeding Oats -- 17 Breeding Soybeans -- Origin and Species -- Genetics -- Botany -- Varieties -- The USDA and Cooperative State Agricultural Experimental Stations -- International Soybean Program (INTSOY) -- Asian Vegetable Research and Development Center (AVRDC) -- Breeding Methods -- Breeding Objectives -- 18 Breeding Corn (Maize) -- Origin -- Races of Corn -- Genetics -- Pollination -- Heterozygous Nature of Open-Pollinated Corn -- Breeding Open-Pollinated Corn -- Hybrid Corn -- Breeding Improved Hybrids -- Population Improvement -- Breeding Objectives -- Special-Purpose Hybrids -- International Maize and Wheat Improvement Center -- 19 Breeding Sorghum and Millet -- Breeding Sorghum -- Breeding Millet -- 20 Breeding Cotton -- Botany, Pollination, and Male Sterility -- Genetics and Cytology -- Varieties -- Breeding Methods -- Variety Maintenance -- Breeding Objectives -- 21 Breeding Sugar Beets -- History of the Sugar Beet -- Botany and Genetics -- Varieties -- Breeding Methods -- Breeding Objectives -- 22 Breeding Forage Crops -- Forage Crop Breeding Problems -- Pollination, Fertilization, and Seed Setting -- Vegetative Propagation -- Genetic and Cytogenetic Studies -- Natural Selection -- Endophytic Fungi: Impact on Grass Breeding -- Breeding Self-Pollinated Forage Species -- Breeding Cross-Pollinated Forage Species -- Public versus Private Breeding of Forage Crops -- Breeding Objectives -- Seed Increase of New Varieties -- 23 Seed Production Practices -- Public and Private Plant Breeding and Seed Distribution -- Classes of Certified Seed -- How a New Variety Reaches the Farmer -- How a Variety is Certified -- Agencies Concerned with Seed Certification in the United States -- Practical Problems in Seed Production -- Vegetatively Propagated Forages.