Biographical Memoirs Volume 44 (1974) / Chapter Skim
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1. Charles Haskell Danforth
1. Charles Haskell Danforth
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Dunn, Roman O'Rahill,, Curt Stern, and Small Wright, the last named providing the evaluation of Danforth's pioneer paper on frequency of mutation in man. Specia]
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Such was r~ature's scenic area that played a role in Danforth's development as a naturalist. AN CESTRY In telling words Danforth wrote: "Most New Englanders of colonial stock have much the same ancestral background and my own is quite typical of the group as a whole." So far as he had been able to learn it seemed probable that all of his immigrant ancestors were exclusively British (English, Scottish, Welsh, and possibly Irish)
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Asa Danforth practiced his profession in Norway for nearly sixty years and seems to have been a typically beloved old-time country doctor. It is said that he built the first woolen mill in the state and was engaged in a variety of town affairs.
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She had "angles," however, that were to be merely tolerated—her attitude toward life was more defiant than humble. On June 24, 1914, Charles Haskell Danforth married Florence Wenonah Garrison, a teacher of science and a member of the Daughters of the American Colonists and the Society of Daughters of the American Revolution, who was a writer of delightful historical articles on the Smithsonian Institution.
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In that year his father sold the farm and took over the home and other holdings of grandfather Haskell in Norway, a village of "perhaps 2000
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Several of us boys were rolling hoops around the square during a long summer twilight when my uncle Frank Danforth, passing by, called me to the sidewalk and gave me two books that he thought I 'might like to have.' They were the two volumes of Darwin's Animals and Plants and er Domestication and the inscriptions on their flyleaves showed that they had long ago been presented to my grandfather Danforth by A
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How much of my subsequent history is due to the strength of this assumption, and how much to chance or lack of imagination, I can not say." But why did Professor Verrill, a distinguished naturalist, discourage young Charles from becoming a naturalist? In an attempt to answer this question it is perhaps of significance "to recall that Verrill lived through practically the entire history of zoology in America, from the coming of Louis Agassiz in 1847, to the experimental period of the present century." The vogue in zoology had changed from taxonomy to comparative anatomy, then to adaptations and other zoological disciplines, and at the beginning of the twentieth century to experimental fields.
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Coe, National Academy of Sciences, Biographical Memoirs, 14 (1929)
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Danforth was added in 1942—a grand total of four Norway Liberal Institute naturalists. The Norway Liberal Institute was opened in 1847 as a selfsupporting academy; it started with 174 pupils, a principal, and a corps of teachers of much ability and enterprise and was ~ncorporated June 25, 1849.
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Charles writes, "I learned much from his intense objectivity, quite unhampered by a highly imaginative and poetic side of his nature." Only a few days after finding a collaborator Charles showed him "a bird's nest containing a foreign egg which I suspected
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Waldo Nash, who had an egg collection, and decided the foreign egg "was indeed that of a cuckoo (a very unusual finds." On the same day Charles learned for the first time of several books on birds available in the public library of Norway. On that same day, therefore, he was introduced to two stimulating naturalists as well as to the works of Baird, Cones, Maynard, and Chapman.
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was a keen observer and had BIOGRAPHICAL MEMOIRS
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Those of an agnostic or frankly atheistic tenor at first distressed Charles greatly. During his boyhood he had been active "in a kind of diffident way" in church and had "taken the Universalist religion for granted, despite an accumulating volume of complexities." With this religious background his first impulse alas to do some "missionary" work against the view of agnosticism.
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14 BIOGRAPHICAL MEMOIRS solute finality is not an attainable goal and oriented my thinking accordingly—in the end, the new approach offered a better basis for 'serenity' than I had previously experienced." A few years later at college he observed with satisfaction, "I was amazed at the number of students who were thrown into mental turmoil by aspects of philosophy which then left me quite undisturbed." Also, although he had never read them before, "Descartes and Kant were to appear almost as old friends and fellow seekers for the same goal." He adds, "Nevertheless 'philosophy' (except as I built up my own!
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"I tried to do so, but with no great enthusiasm." During the year after graduation, which he characterized as "Transitional Year 1903-1904," Charles wrote a diary or autobiographical sketch of "my first twenty years," which unfortunately was lost. In the sketch written when he was sixty-five, however, Charles saw himself "in a clearer light now t1948]
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As it happened, I did just that, and then drifted on to baccalaureate and advanced degrees." BIOGRAPHICAL MEMOIRS A NATURALIST AT COLLEGE When Charles entered college he was nearly two years older than the average freshman student and accordingly thought of himself as much more "adult" than many classmates and in
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Of broader appeal was the rural village of Concord and nearby Walden Pond, a region that boasted an unusual concentration of distinguished original thinkers—poets, philosophers, and/or naturalists. Charles had long been familiar—ever since as a boy of high school age he became a member of Howe's naturalist club—with Nature, a book by Ralph Waldo Emerson, and Walden; or, Life in the Woods by Henry D
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He became a member of the New England Botanical Club and frequently attended meetings of the Boston Society of Natural History. With a natural bent for the theoretical and having been previously influenced by Darwin and Louis Agassiz, Danforth was prepared to seek knowledge of the processes by which life develops from an egg and thus gain an understanding of nature 1 vie ~ V in general.
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(It may be noted here that nothing came of this work until later, when it served as the dissertation for the master of arts degree awarded to him in 1910 by Tufts College.) Then, quite suddenly Danforth received from Professor R
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Further, he was occasionally invited to the meetings of the distinguished BIOGRAPHICAL MEMOIRS
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Danforth's "necessary association with recently dead bodies" was so repugnant to him that it took time before he "could think of no better final dissolution than being dissected by two eager medical students." The question of a doctoral degree naturally arose soon after he entered the university. It seemed desirable to prepare for either an M.D.
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He also became acquainted with the work of the Eugenics Record Office, an institution then devoted to the study of human heredity, factors of race betterment, and improvement of the inborn traits of the race. Thereupon he became active in the study of human heredity, as his record of publication shows, and offered a course in heredity for medical students.
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Thus began an interest that brought him into local and national organizations. He subscribed to the very first volume of the American Journal of Physical Anthropology, founded in 1918 by Ales Hrdlicka, and later served on the editorial board of that journal.
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24 BIOGRAPHICAL MEMOIRS his family returned to the Norway country that he loved so much as a boy. Sometime during the year 1921 he was invited by Dr.
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The course on human heredity, which he first organized and gave to medical students in 1914 at Washington University, was offered each year from 1926 to his retirement at Stanford. The course dealt with the facts and problems of heredity in relation to the individual and the population as a whole.
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In 1942 Charles Haskell Danforth was elected to the National Academy of Sciences. SCIENTIFIC WORK—AN APPRAISAL Among the first publications by Danforth were those concerned with the morphology of a marine snail (a study of a new species)
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in the flower head of the common daisy, a composite plant. By comparing the number of ray florets of plants from three different geographical regions, Danforth was able to show a relation between mode (number of ray florets)
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Indeed, it is possible that spirogyra "is inherently periodic in its functions, although its periodicity may be extensively influenced by its environment." Very soon Danforth turned away from problems of variation and speciation in plants—never to return to them—to the field of human heredity, a-field in which he was to excel as a contributor of new knowledge. As an anatomist and a teacher of anatomy, Danforth intuitively felt morally obligated to include man among his own investigations.
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, Danforth in 1916 pointed out that 29+ percent of all twin cases are monozygotic, whereas the number of monozygotic twins given in textbooks of obstetrics is about 15 percent when based on the relations of fetal membranes. The difference between 15 percent and 29+ percent represents the number of cases in which monozygotic twins develop in separate sets of fetal membranes.
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It might therefore be predicted that monozygotic twins would differ from each other in the same respects and to the same degree as two sides of the body differ in ordinary individuals. The theoretical considerations discussed by Danforth serve to account for most of the resemblances and differences actually observed among twins; also they aid in understanding why monozygotic twins are not absolutely identical and why dizygotic twins are very often closely similar.
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By such a view one may account for mirror-image duplicates of hair whorls and other dissimilar features in like twins. Danforth also carried out an analytical study of structural anomalies of the foot of the common domestic fowl in which he was concerned with the kinds of factors that have a "determining influence" on the ontogeny of brachydactyly.
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The estimated gene frequency being about one in two thousand in both, his estimates for the mutation rates were both about one in six thousand. He noted, however, the likelihood that this estimate of persistence from pedigrees was less than the actual persistence, so that the true mutation rates might be considerably less than one in six thousand.
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J Duller, who had listened to Danforth's address at the 1921 Congress of Eugenics, called attention to Danforth's pioneering role and used his principle extensively in developing his concept of "genetic load" with special reference to man.
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were more than an order of magnitude smaller than Danforth's estimate for polydactyly and syndactyly. "Whatever the difficulties in using his particular formula, Danforth's paper should clearly be credited with being the first to point out the possibility of using the principle of equilibrium in calculating human mutation rates." His work on the frequency of mutation in man was only one phase of a broader program of investigations.
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Thus Danforth has brought the subject of polydactylous limb development to the very threshold of contemporary embryological formulation. His idea that excess digital tissue is the direct function of the dominant gene is in consonance with the discovery of E
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How are these characteristics and potentialities acquired? Danforth searched for the answer in the developmental arrangement of hair follicles in the neonatal mouse, that is, before hair papillae are visible.
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With his expert knowledge of comparative anatomy and of human heredity, Danforth raised the question of homologies of hair, the "most distinctive characteristic of mammals," the "highest" class of vertebrates. From a thorough analysis of observations bearing on homologies of hair, he was able to present a thought-provoking new theory.
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On research productivity with mice, Danforth facetiously remarked: "Few, I think, have raised more mice and kept more extensive pedigrees in proportion to their published papers." At the outset Danforth envisaged the value of using mice for the study of mutations under controlled conditions. More specifically, he had in mind a study of the genetic makeup of the anomalous individual and the embryonic development of its structural anomalies.
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It is clear from the foregoing considerations that Danforth fully recognized the value of posterior duplications and of other abnormal variants in their bearing on the nature of developmental and/or morphogenetic processes. As will be immediately apparent, he did not continue the challenging problems that he .
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The common domestic fowl, owing to racial differences in feather color and/or color pattern, afforded excellent material for analyzing the interplay of developmental factors in feather differentiation. For such an analysis Danforth used the very simple technique of grafting pieces of skin from one newly hatched chick to another of different breed.
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Twelve years after it was discovered that the melanin pigmentation of feathers is a phenomenon dependent on highly autonomous migratory pigmentoblasts, Danforth concluded that these feather mosaics are truly pigment-cell mosaics, the product of two pigment cells that differ in genotype. Another fixed potentiality in the skin at hatching is the responsiveness of the feather germ to sex hormone; for example, if the host is genetically male, the graft feather germ produces a contour feather that is structurally male, a form brought about by a hormonally altered type of morphogenesis.
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; (b) feather follicles that react to either male or female sex hormones; feathers produced in skin grafts follow the breed of the donor but the sex of the host (all breeds of the common domestic fowl—nine tested)
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During development, a new adjustment comes about in the feather germ which imparts to it the capacity to utilize hormones in the making of sex differences not only in form but also. if venotvn,~ n``rmitc in ruler m~rlr;~rr of feathers.
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—better still, an interaction between hormonal molecules and receptor organ—a mutual fitting together of hormonal molecules and prospective epidermal cells, cells that synthesize keratin as they "build" the framework of the definitive feather. From this standpoint of original thought and interpretation, no one has excelled Danforth in presenting the characteristic features associated with feather follicles in the form of concepts that are not only original but still sound today.
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Danforth regarded the loss as slight, "for what one biologist does not do, some other one will" (a paraphrase of a saying by Professor Herbert .S If~nnin~c of The Tohns Hookins University _ _~ ~ an- J ~~~v ~~ _ 1 ~ / In an "epilogue" to his autobiographical sketch l:) anforth comments on research interests and motivations: "My natural inclination has been strongly toward leisurely observation (vs.
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The writer of this memoir now ventures to speak less formally, in the name of all Charles Haskell Danforth's friends, dead or living. We loved and respected him.
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As Ralph Waldo Emerson said at the funeral of another naturalist, Henry David Thoreau: Wherever there is knowledge, Wherever there is virtue, Wherever there is beauty, He will find a home.
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- American Journal of Physical Anthropology Am. Naturalist American Naturalist Gnat.
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The developmental relations of brachydactyly in the domestic fowl.
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The cycling activities of hair follicles.
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Med., 23: 305-8. The developmental arrangement of hair follicles.
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Anat., 41:65-74. lg29 The effect of foreign skin on feather pattern in the common fowl (Gallus domesticus)
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1933 Genetic factors in the response of feather follicles to thyroxin and theelin.
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Med., 33:291-92. Genetic mosaics in the feathers of the common fowl.
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Part II. In: Hormonal Factors in the Inversion of Sex.
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Genetics, 43: 139-48. Callus sonnerati and the domestic fowl.
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