Heredity and Social Fitness: A Study of Differential Mating in a Pennsylvania Family, Issue 296

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Carnegie institution of Washington, 1920 - Eugenics - 102 pages
 

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Page 2 - OF THE STATION FOR EXPERIMENTAL EVOLUTION AT COLD SPRING HARBOR, NEW YORK PRESS OF GIBSON BROTHERS INC. WASHINGTON CONTENTS.
Page 97 - ... with the New Immigration, one would not imagine keeping out any particular racial group as such. As Key puts it (59, p. 97) : The vital point . . . would seem to be, not whether there has been amalgamation in a general sense, but what sort of amalgamation has resulted (from immigrant stocks). . . . Heredity studies are showing wide diversity in our native stocks, and it is a significant fact that, with incoming strains, those of low potentiality inevitably amalgamate with the lowest elements...
Page 5 - The study comprises nearly two thousand individuals, about one-half of whom are in the direct line of descent from two pairs of pioneers, the remainder being members of the families into which the direct descendants married.
Page 80 - The realized percentages support the following conclusions: (1) When both parents show a low grade of this ability, all the children are similarly of low grade. (2) When both parents show high ability, practically all the children are similarly endowed. (3) When one parent shows a low grade and the other a medium or high grade the increase in the percentage of medium and high is proportionate to the grade of the abler parent. Although a small proportion of low grades...
Page 97 - ... average intelligence of the older stock is high, the range of abilities reaches from distinct feeble-mindedness on the one side to genius on the other. So with the New Immigration, one would not imagine keeping out any particular racial group as such. As Key puts it (59, p. 97) : The vital point . . . would seem to be, not whether there has been amalgamation in a general sense, but what sort of amalgamation has resulted (from immigrant stocks). . . . Heredity studies are showing wide diversity...
Page 78 - ... persisted at the low level of the original founders. In the same way the trait-complex perseverance is found to move up or down in fair accord with the type of mating made. Let us now see how far the behavior of these abilities in inheritance conforms to the Mendelian hypothesis. At the outset, we concede that our data, since they appertain to mental and temperamental traits, do not permit of the accuracy of measurement possible in handling physical traits. It will, however, be generally agreed...
Page 85 - ... physical and mental tests in determining types of efficiency in the National Army, gives promise of far more accurate ratings in future studies of this kind. By such means this principle of segregation should be found capable of extension in directions at present unthought of. Such extension would provide a means of more accurate prediction as to the outcome of given matings and the trend of development in particular strains. Such extension would prove highly valuable for constructive eugenics....
Page 83 - ... accordance with the theory of segregation of determiners for the trait-complex. The slightly wider discrepancy between the expected and the realized results is no doubt due to the difficulty of evaluating the character. It will be observed that the discrepancy is considerable only where both parents are moderately aggressive, or where one has a very low grade while the other has a high grade of the trait. In both cases, the offspring show greater resemblance to the parents than the hypothesis...
Page 78 - ... aggressiveness, perseverance and the ability to handle number was noticeably increased or diminished. For example, in Line E the absence of such abilities with the concomitant failure of the individuals to marry those possessing the abilities in question persisted through five generations. In Line C a comparatively low ability to calculate has, through selective matings with good or average ability, been built up into ability which is average or in some instances even above the average. This...
Page 62 - Eugenia had been left an orphan at an early age, and brought up in the midst of a people who still clung fervently to all the old-world superstitions.