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James Tabery 《Journal of the history of biology》2008,41(4):717-761
This essay examines the origin(s) of genotype–environment interaction, or G × E. “Origin(s)” and not “the origin” because the thesis is that there were actually two distinct concepts of G × E at this beginning: a
biometric concept, or G × EB, and a developmental concept, or G × ED. R. A. Fisher, one of the founders of population genetics and the creator of the statistical analysis of variance, introduced
the biometric concept as he attempted to resolve one of the main problems in the biometric tradition of biology – partitioning
the relative contributions of nature and nurture responsible for variation in a population. Lancelot Hogben, an experimental
embryologist and also a statistician, introduced the developmental concept as he attempted to resolve one of the main problems
in the developmental tradition of biology – determining the role that developmental relationships between genotype and environment
played in the generation of variation. To argue for this thesis, I outline Fisher and Hogben’s separate routes to their respective
concepts of G × E; then these separate interpretations of G × E are drawn on to explicate a debate between Fisher and Hogben
over the importance of G × E, the first installment of a persistent controversy. Finally, Fisher’s G × EB and Hogben’s G × ED are traced beyond their own work into mid-20th century population and developmental genetics, and then into the infamous
IQ Controversy of the 1970s. 相似文献
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《Parasitology today (Personal ed.)》1986,2(1):27-28
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Dobson SD 《Journal of human evolution》2005,49(1):143-154
Recent studies of early hominin body proportions paint a complex evolutionary picture, with multiple instances of reversal in body shape. These interpretations rest heavily upon the inferred limb joint proportions of Australopithecus africanus. For example, the partial skeleton Stw 431 has been suggested to show ape-like joint proportions compared to the A. afarensis specimen A.L. 288-1. This suggests an evolutionary reversal in the more recent A. africanus. However, no study has examined the probability of sampling the differences between Stw 431 and A.L. 288-1 from a single extant hominoid species. The present study compares elbow/hip and elbow/lumbosacral joint size ratios between Stw 431 and A.L. 288-1 using exact randomization, based on chimpanzee and human models of variation. Results indicate that differences in elbow/hip proportions between Stw 431 and A.L. 288-1 can be sampled from a single species. In contrast, differences in elbow/lumbosacral proportions between Stw 431 and A.L. 288-1 show a significantly low probability of being sampled from a single species. Thus, Stw 431 and A.L. 288-1 are not significantly different from each with regard to limb joint proportions, but Stw 431 has a significantly smaller lumbosacral joint. This pattern does not conform to previous interpretations of limb proportions in A. africanus. Low statistical power in the present study may account for the discrepancy. Further research is needed to illuminate the functional implications of variation in relative lumbosacral joint size in early hominins. 相似文献
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Carel J. van Oss 《Preparative biochemistry & biotechnology》2013,43(3):375-376
ABSTRACT Covalent structural information on membrane proteins is not easily acquired since it is difficult to obtain pure membrane proteins in sufficient quantities. We have therefore examined the Bio-Rad 491 prep cell continuous elution electrophoresis apparatus as a method for providing the quantities of purified , alpha and beta subunits from (Na.K)-ATPase required for these studies. Twenty-four milligrams of crude (Na.K)-ATPase preparation was applied to the prep cell which consisted of a 7% Laemmli separating gel 4.5 cm in length. The prep cell was Y run under constant power and continuous cooling conditions. Those fractions containing the beta subunit were combined and further purified by wheat germ agglutinin affinity"' chromatography. Fractions containing the alpha subunit were combined and did not require further purification. The identity and the degree of purity of the proteins obtained using this approach was assessed utilizing SDS-PAGE, amino acid analysis 375 Copyright 1993 by Marcel Dekker, Inc. * and N-tertninal sequencing. This simple and fast method provides approximately 1.8 milligrams of each purified subunit from 24 milligrams of relatively crude microsomes. Recovery of the alpha and beta subunits from the crude (Na.K)-ATPase preparation was estimated to be 28% and 81%, respectively. 相似文献
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《European journal of protistology》2014,50(5):593-605
The morphology and infraciliature of two hypotrichous ciliates, Urosoma salmastra and U. karinae sinense nov. sspec., were investigated for populations collected from the surface of intertidal gravel in the Huguang Mangrove Forest, Zhanjiang, China and the upper 10 cm layer of soil in the Sangke Grass Land in the southern part of Gansu Province, China, respectively. Urosoma salmastra is characterized by its elongate-elliptical body with no tail-like structure; two macronuclear nodules; cortical granules colourless, less than 1 μm across, and arranged in short rows; adoral zone occupying 25% of body length in vivo; paroral conspicuously short and located in front of endoral. Urosoma karinae sinense nov. sspec. is characterized by its elongate-elliptical body with no tail; 2–4 macronuclear nodules; cortical granules colourless, less than 1 μm across, and arranged in short rows; adoral zone occupying 30% of body length in vivo; paroral shorter than, and located ahead of endoral. Phylogenetic analyses based on SSU rRNA gene sequence data suggest a close relationship between U. salmastra, U. karinae sinense nov. sspec. and Oxytricha granulifera within the Oxytrichinae assemblage. 相似文献
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A study was made on Fritillaria cirrhosa D.Don and its related species based on both field observation and herbarium material.As a result,four species are recognized and 16 specific names and 18 variety names are reduced as synonyms. 相似文献
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