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1876
Francis Galton (1822-1911) offers a statistical approach to understanding inheritance
Soon after publication of Charles Darwin's Origin of Species, Francis Galton undertook studies of how various traits might be transmitted from parent to offspring. His early experiments, in which he injected rabbits with blood drawn from other rabbits of different colored coats, tested a speculative theory known as "pangenesis." As Galton soon realized, that theoryin which particles in the blood were thought to carry hereditary informationwas incorrect.
The "law of ancestral heredity," as it turned out, was mistaken. Although he was interested in individual variations, Galton's mathematical methods treated them as "errors." In Gregor Mendel's more carefully conceived experiments with culinary peas, variations represented the expression of discrete alternative factors or (as we would say today) genes. Galton, in his personal correspondence with Darwin, came close to this conception, but never proceeded to a testable formulation. In accordance with his view that "heredity was a far more powerful agent in human development than nurture," Galton also became a principal founder of eugenics. This social movementGalton coined the term in 1883had as its aim improvement of humanity through selective breeding. By preventing certain persons from having children, while encouraging others, eugenicists hoped to improve whole populations. Eugenics was a powerful movement for several decades in the twentieth century, but today most of its principles and aims are mistrusted or discredited. Galton remains one of the founders of biometrics, the application of statistical methods to biological phenomena. His research into mental abilities and dispositions, which included studies of identical twins, were pioneering demonstrations that many traits are inherited. Galton's passion for measurement led him to open the Anthropometric Laboratory at the International Health Exhibition in 1884, where he collected statistics on thousands of people. In 1892 Galton invented the first system of fingerprinting. Adopted by police departments all over the world, fingerprinting was the most reliable form of identification in forensicsuntil the advent of DNA technology in the late twentieth century. |
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