DOCSLIB.ORG

Integration of the Ecospecies

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Integration of the Ecospecies January, 1953 REVIEWS 233 creased the usefulness of his book by listing and the principles and laws will be tested by them for reference and citing them in the proper comparison, discussion and new investigations. place in the text. PIERRE DANSEREAU As it stands, the book is certain to offer much DEPARTMENT OF BOTANY, stimulation to further research and exploration. UNIVERSITY OF MICHIGAN, The descriptions will be developed by local study ANN ARBOR, MICHIGAN INTEGRATION OF THE EcoSPECIES 1 The etetnally disputed definition of species is very mechanisms observed are sure to be quite very sharply focused in Jens Clausen's book, different in other parts of the world with broad "Stages in the evolution of plant species." The instead of narrow life zones. Stebbins for in­ outstanding merit of this work is that it sum­ stance (Am. Nat., 86 (826) : 34, 1952) ventures marizes very lucidly the experiments on the na­ to "predict that the diversity of ecotypes of ture of species which Hall had begun but which individual species, when investigated will prove are principally Clausen's own work and that to be considerably less" in the Eastern States of his collaborators David D. Keck and Wm. M. than in California. Hiesey at the Carnegie Institution of Washing­ The book consists of eight chapters. The first ton's Department of Plant Biology in Stanford, two offer a brief historical perspective in which California. The past decade has been a very the growing influence of genetics on taxonomy fruitful one for this group, as the essentials is emphasized. The principal currents are out­ and much of the detail of their experimental lined: Darwin's keen observations of variation work have been made known in print. The in nature and its obedience to natural selection; soundness of their method, the thoroughness of the experimental approach and discovery of the their investigations and the variety of their mechanics of heredity by Mendel's successors. respective backgrounds offered unique guaran­ These two traditions, which to some extent had tees of original and significant research. Their followed separate courses, are joined harmoni­ three book-length memoirs and their many ously in Turesson's work. The often over­ shorter papers had provided us with a great looked evolutionary ideas of Linnaeus in his later wealth of new materials and many leads to new years are quoted as marking the beginning of a interpretations. The present book goes a step "modern" point of view. Jordan is credited beyond this and outlines Clausen's (and pre­ with the discovery of the local population. sumably his collaborators') emergent concept This is the subject of the third chapter, "The of speciation. This is far-reaching indeed, al­ local population as the basic evolutionary unit." though the author does not pretend to review Here the author's working principles are clearly the whole field of experimental taxonomy, even stated: "It is at the level of the local popula­ less the more general topic of evolution. In tion that all of the selective forces act upon fact, it justifies its title perfectly by casting the genetic resources of the population." This complete emphasis on experimentally known statement is well illustrated and substantiated cases of perfect to imperfect to inadequate iso­ by examples from the genera Layia, Viola, lation of taxa in the Western North American Potentilla, and Achillea. Following the best in environment. Some of the author's earlier work taxonomic tradition, intra-population and inter­ in Northwestern Europe is also quoted, as are population variations are compared and found Brainerd and Gershoy's in Eastern North to be of a different order of magnitude (p. 26). America. But no one will quarrel with Clau­ However, these analyses are always made in sen's dwelling principally on what he knows the light of the deeper-lying physiological re­ best : a central Californian transect from the sponses which are elicited by the heredity vs. Pacific across the coastal ranges and inner val­ environment contest. Thus: "It is probable leys to the slopes and summits of the Sierra that the intrapopulation variation enables a spe­ Nevada, thence down to the deserts of the Great cies to tolerate periodic variations in the cli­ Basin. Such a transect lends itself extremely mate at any one locality." well to a test of evolutionary processes as it These various points are strikingly illustrated provides strongly contrasting environmental by experimental data, the conclusiveness of which backgrounds at close intervals. Even though is quite incontestable. One might wish, how­ such telescoping is not unique, it is in many ever, that Clausen's rejection of other tech­ ways peculiar and the rates of change and the niques for estimating populations "growing in the wild and therefore subjected to uncontrolled 1 Clausen, Jens. 1951. Stages in the evolu­ modifications in many environments" were the tion of plant species. viii + 206 pp., 76 figs., object of further discussion. The work of Ed­ Ithaca: Cornell University Press, $3.75. gar Anderson, Fassett, and Woodson is not men- 234 REVIEWS Ecology, Vol. 34, No. 1 tioned. It would be interesting to compare pur­ Thus some local populations of both subspecies pose and achievement in both cases and to out­ share the same amounts of rainfall and heat line what aspects of environmental integration except inasmuch as their habitats ("sunny slope" are revealed by these different means. It seems, and "meadow") utilize the meteorological ele­ however, that both groups will agree that ments differently and eventually provide the "clines are not commensurable with natural en­ plants themselves with rather different amounts tities," if by the latter are meant formal taxa. of heat and water, and at different times also. The fourth chapter concerns "the evolution of There is here an ecological dimension that fits ecological races." Whereas the preceding chap­ into a climatic dimension. There is also the ter had not provided a hard and fast definition further question of ecological amplitude, not of the local population, the present definition of necessarily similar or even parallel to climatic the ecological race may seem unsatisfactory: tolerance. 2 Although these issues are certainly "An ecological race is usually composed of a present in the author's mind, they are not as considerable number of variable local populations sharply focused as the corresponding morpho­ existing within a given ecological zone." This logical and genetic aspects. latter term itself is not defined either, except by In the fifth chapter the genetic systems which implication. A short paragraph on parts of underlie the adjustment of taxa are reviewed, pp. 50-52 states that "these major sets of fac­ whether or not the units involved show any tors in the environment have been decisive in morphological discreteness. The point is well the development of ecological races, namely, made that some formerly adaptive features are climate, soils, and other organisms. All of able to persist after a shift and even a reversal these three are interrelated and contribute to in the .kind of environmental pressure exerted. natural selection, but climatic, edaphic, or biotic Thus a "typically maritime" Viola tricolor (from ecotypes can be recognized, depending upon Denmark) was grown in inland California and which of these sets of factors has been rela­ eventually sowed itself in a garden at Santa tively the most dominant." Rosa, maintaining its identity under "drastic I can voice no objection to the above state­ changes." s ments but I am afraid they lend themselves to Several good examples are provided here that a variety of rather divergent applications. illustrate the degrees of effectiveness in genetic Whereas a constant attempt is being made to isolation. It is assumed that the best proof assess morphological, genetic, cytological and thereof lies in the failure to cross-breed or in physiological criteria and to assemble them in the relative weakness of the offspring. Thus a discriminating way so as to reflect a natural the background is drawn for the principal argu­ hierarchy (Chapter VIII), and whereas the ment of the book which will culminate in a magnitude of each "stage in the evolution of grading (Chapter VIII) of the isolating mecha­ plant species" is graded, no corresponding nisms. The largest stock of evidence along hierarchy in the environment as a whole is in­ these lines is drawn from taxa indigenous to at dicated. Transgressions by the segments of a least one of the three stations (Stanford, species beyond the barriers of biotope, com­ Mather, Timberline) operated by Clausen and munity, habitat, climatic zone are not recog­ his collaborators. The relative frequency of nized explicitly as such. successful experimental crossing on the one Clausen does not say that hierarchy in en­ hand, and the degree of survival and "vigour" vironment (a) does not exist ; ( b) is too com­ plex to be measured effectively; ( c) is not sig­ 2 A plant like Chamaedaphne calyculata ranges nificant, since the ultimate unit alone is con­ from the near-Arctic to the mountains of sidered. For instance, Figure 5 (p. 20) shows Georgia, is exposed to a variety of severe and 4 subspecies of Potentilla glandulosa as they oc­ mild climates. Ecologically it is very narrow, cur from 900 to 11,000 feet on the west slope however, being strictly confined to bogs, and of the Sierra Nevada. As far as major climatic even to a certain phase of bog formation. On and vegetation zones· are concerned, 6 distinct the contrary, Betula populifolia has rather a units are involved: 1) the oak savana, 2) the yel­ narrow range (Atlantic-North Appalachian) low pine forest (or woodland), 3) the red fir but very wide ecological amplitude : sand plains, forest, 4) the lodgepole pine woodland, 5) the bogs, old fields, stream edges, rock outcrops, white-bark pine scrub and 6) the alpine meadow.
Load more

Recommended publications
  • The “Plant Drosophila”: E. B. Babcock, the Genus Crepis, and the Evolution of a Genetics Research Program at Berkeley, 1915–1947
    HSNS3903_02 6/26/09 11:04 AM Page 300 ∗ VASSILIKI BETTY SMOCOVITIS The “Plant Drosophila”: E. B. Babcock, the Genus Crepis, and the Evolution of a Genetics Research Program at Berkeley, 1915–1947 The student of genetics must be ready to resort to the use of any living organism that gives promise of revealing the natural laws upon which the future science of breeding will be grounded. E. B. Babcock, 19131 The Crepis investigations carried on by the Babcock group are the American evolutionary investigations that seem to have attracted the largest attention outside of America next to the Drosophila investigations. One reason for this is their wider systematical aspect. Jens Clausen, 19342 *Departments of Zoology and History, Affiliate in Botany, University of Florida, Bartram Hall, Gainesville, FL 32611; [email protected]fl.edu, [email protected]fl.edu. The following abbreviations are used: APS, American Philosophical Society Library, Philadel- phia, PA; CAS, California Academy of Sciences, San Francisco, CA; CIW, Carnegie Institution of Washington; CP, Carnegie Papers, Missouri Botanical Garden Archives, St. Louis, MO; EBB, Ernest Brown Babcock Papers, TBL; JHB, Journal of the History of Biology; JAJ, James Angus Jenkins Papers, TBL; RG, Rockefeller Foundation Archives, Sleepy Hollow, NY, http://www.rockarch.org/collections/rf/; TBL, The Bancroft Library, University of California, Berkeley; UC, University of California; UCGD, University of California, Berkeley, Genetics Department, APS. Interviews with G. Ledyard Stebbins are transcribed and in the author’s possession. 1. “Division of Genetics: Report to the Director of the Experiment Station, 11 June 1913,” EBB, Folder The Division of Genetics of the Department of Agriculture.
    [Show full text]
  • Darwin Tried and True: Review of Jerry
    Scientists’ Bookshelf Darwin Tried and True Robert J. Richards WHAT DARWIN GOT WRONG. Jerry Fodor and Massimo Piattelli-Palmarini. xxii + 264 pp. Farrar, Straus and Giroux, 2010. $26. n November of 1859, when Charles ality on the part of nature; he preferred Herbert Darwin excitedly held in his hands the first Spencer’s phrase survival of the fittest. I published copy of On the Origin of Species, In the 1930s and 1940s, with the synthesis of virtually no reputable naturalist in England, modern genetics and Darwinian theory—pre- on the Continent or in America accepted the pared by such leading neo-Darwinists as Ernst proposition that species had altered over Mayr, Sewall Wright, Theodosius Dobzhansky, vast periods of time. The conception itself R. A. Fisher, Julian Huxley and J. B. S. Hal- was not new: Jean-Baptiste de Lamarck had dane—the device of natural selection was ce- advanced it at the beginning of the 19th mented into the foundation for most subsequent century, as had Darwin’s own grandfather work in evolutionary biology. Nonetheless, sev- Erasmus Darwin at the end of the 18th. Even eral of the 19th-century objections to natural Immanuel Kant entertained the hypothesis, selection have been reinvented and advanced although he rejected it for lack of evidence. by Jerry Fodor, a distinguished philosopher of By the time Darwin died in 1882, however, mind, and Massimo Piattelli-Palmarini, a cog- hardly a naturalist of standing could be found nitive psychologist, in their book What Darwin who denied the transmutation of species, so Got Wrong. In the view of the authors, Darwin utterly convincing was the argument of his and the neo-Darwinians got almost everything great book.
    [Show full text]
  • BOOK REVIEWS Evolution, 55(3), 2001, Pp
    BOOK REVIEWS Evolution, 55(3), 2001, pp. 641±646 THE LIFE AND TIMES OF PLANT SPECIES: FROM METAPOPULATIONS TO MUTATIONAL MELTDOWN1 SPENCER C. H. BARRETT Department of Botany, University of Toronto, 25 Willcocks Street, Toronto, Ontario, M5S 3B2 Canada E-mail: [email protected] Received December 6, 2000. Flowering plants are among the most species-rich groups middle of the twentieth century. During the 1950s and 1960s, of organisms, and there are few habitats on earth that they the biosystematic approach, led by Ledyard Stebbins, Verne have not been able to invade. Close to a quarter of a million Grant, and Herbert Baker, amassed a huge amount of infor- species have now been described, with countless more that mation on chromosomal evolution, polyploidy, crossing re- have become extinct since the early Cretaceous, when the lationships, and the regulation of recombination, all directly angiosperms are thought to have originated. What is the key relevant to speciation. In the 1960s, with the development of to understanding their ecological and evolutionary versatil- population biology, ®eld experiments were routinely used for ity? Is the principal mechanism responsible for angiosperm testing ecological and evolutionary hypotheses, with John diversi®cation simply ecological adaptation to the countless Harper and Tony Bradshaw being the most in¯uential. Cu- environments suitable for plant life? You would think that riously, despite this early impetus few modern workers have after two centuries of experimental work on plant evolution directly linked ecological studies of the adaptive divergence (reviewed in Langlet 1971) and the early lead taken by ge- of populations to the evolution of reproductive barriers.
    [Show full text]
  • Experimental Taxonomy, 1930-1950: the Impact of Cytology
    AN ABSTRACT OF THE THESIS OF Joel Bartholemew Hagen for the degree ofDoctor of Philosophy in General Science (Biological Science)presented on 31 July 1981 Title: Experimental Taxonomy, 1930-1950: The Impact of Cytology, Ecology, and Genetics on Ideas of Biological Classification Redacted for privacy Abstract approved: Paul Lawrence Farber During the years between 1930 and 1950 a number of attempts were made to introduce techniques and ideas from cytology, ecology, and genetics into the field of taxonomy. Advocates of this "experimental taxonomy" believed that cytological, ecological, and genetic techniques would provide a rigorous, objective methodology to replace the traditional descriptive methods of taxonomy. Between 1930 and 1950 a number of impressive experimental taxonomic research programs were instituted. Despite the enthusiastic activity in experimental taxonomy, the introduction of cytological, ecological, and genetic methods into taxonomy was problematic. Taxonomists who borrowed from other biological fields were not taking methods and ideas from fully "mature" sciences. Cytology, ecology, and genetics were themselves going through major theoretical and methodological changes. The integration of methods and ideas from a number of complex, semi-autonomous biological disciplines was difficult. Experimental taxonomists, themselves, disagreed on the form this integration should take. Finally, although experimental taxonomy proved to be a viable and fruitful line of research, it did not constitute a complete reform of general taxonomic
    [Show full text]
  • The Balance Between Coherence and Variation in Evolution by Jens Clausen and Wm
    494 BOTANY: CLAUSEN AND HIESEY PROC. N. A. S. to fresh medium, especially when small inocula are involved. increased formation of acetylorni- thine permease appears to take place (Vogel, H. J., unpublished data). 23 Magasanik, B., A. K. Magasanik, and F. C. Neidhardt, in Regulation of Cell Metabolism, ed. G. E. W. Wolstenholme and C. M. O'Connor (Boston: Little, Brown and Company, 1959), p. 334. THE BALANCE BETWEEN COHERENCE AND VARIATION IN EVOLUTION BY JENS CLAUSEN AND WM. M. HIESEY DEPARTMENT OF PLANT BIOLOGY, CARNEGIE INSTITUTION OF WASHINGTON, STANFORD, CALIFORNIA Read before the Academy, November 18, 1969 What are the mechanisms that cause living things to differentiate into recogniz- able species and subspecific entities rather than to evolve into a flow of continuous variation? This age-old question has puzzled evolutionists, and no adequate answer has been demonstrated. One of the reasons for our highly fragmentary understanding of evolutionary processes is that only scant information has been available about mechanisms governing variation in truly wild organisms. A recently concluded analysis of 20-year experiments on the hereditary mecha- nisms that separate ecological races of wild plants of western North America shows that coherence is as much a part of evolution as is variation. Even characters of evolutionary entities below the level of the species are held together by coherence mechanisms that are balanced against others producing variation. The fact that the forces of coherence are as integral a part of evolutionary mechanisms as are the forces of variation makes the process of speciation comprehensible. Studies on the mechanisms of inheritance in wild organisms have hitherto largely been avoided because their inheritance has been known to be relatively complex.
    [Show full text]
  • The Flowering of Natural History Institutions in California
    The Flowering of Natural History Institutions in California Barbara Ertter Reprinted from Proceedings of the California Academy of Sciences Volume 55, Supplement I, Article 4, pp. 58-87 Copyright © 2004 by the California Academy of Sciences Reprinted from PCAS 55(Suppl. I:No. 4):58-87. 18 Oct. 2004. PROCEEDINGS OF THE CALIFORNIA ACADEMY OF SCIENCES Volume 55, Supplement I, No. 4, pp. 58–87, 23 figs. October 18, 2004 The Flowering of Natural History Institutions in California Barbara Ertter University and Jepson Herbaria, University of California Berkeley, California 94720-2465; Email: [email protected] The genesis and early years of a diversity of natural history institutions in California are presented as a single intertwined narrative, focusing on interactions among a selection of key individuals (mostly botanists) who played multiple roles. The California Academy of Sciences was founded in 1853 by a group of gentleman schol- ars, represented by Albert Kellogg. Hans Hermann Behr provided an input of pro- fessional training the following year. The establishment of the California Geological Survey in 1860 provided a further shot in the arm, with Josiah Dwight Whitney, William Henry Brewer, and Henry Nicholas Bolander having active roles in both the Survey and the Academy. When the Survey foundered, Whitney diverted his efforts towards ensuring a place for the Survey collections within the fledgling University of California. The collections became the responsibility of Joseph LeConte, one of the newly recruited faculty. LeConte developed a shared passion for Yosemite Valley with John Muir, who he met through Ezra and Jeanne Carr. Muir also developed a friendship with Kellogg, who became estranged from the Academy following the contentious election of 1887, which was purportedly instigated by Mary Katherine Curran.
    [Show full text]
  • Percival Bailey 3 by Paul C
    http://www.nap.edu/catalog/1645.html We ship printed books within 1 business day; personal PDFs are available immediately. Biographical Memoirs V.58 Office of the Home Secretary, National Academy of Sciences ISBN: 0-309-59745-5, 556 pages, 6 x 9, (1989) This PDF is available from the National Academies Press at: http://www.nap.edu/catalog/1645.html Visit the National Academies Press online, the authoritative source for all books from the National Academy of Sciences, the National Academy of Engineering, the Institute of Medicine, and the National Research Council: • Download hundreds of free books in PDF • Read thousands of books online for free • Explore our innovative research tools – try the “Research Dashboard” now! • Sign up to be notified when new books are published • Purchase printed books and selected PDF files Thank you for downloading this PDF. If you have comments, questions or just want more information about the books published by the National Academies Press, you may contact our customer service department toll- free at 888-624-8373, visit us online, or send an email to [email protected]. This book plus thousands more are available at http://www.nap.edu. Copyright © National Academy of Sciences. All rights reserved. Unless otherwise indicated, all materials in this PDF File are copyrighted by the National Academy of Sciences. Distribution, posting, or copying is strictly prohibited without written permission of the National Academies Press. Request reprint permission for this book. i e h t be ion. om r ibut f r t cannot r at not Biographical Memoirs o f NATIONAL ACADEMY OF SCIENCES however, version ng, i t paper book, at ive at rm o riginal horit ic f o e h t he aut t om r as ing-specif t ion ed f peset y http://www.nap.edu/catalog/1645.html Biographical MemoirsV.58 publicat her t iles creat is h t L f M of and ot X om yles, r f st version print posed e h heading Copyright © National Academy ofSciences.
    [Show full text]
  • Topographically Varied. As the Mountains Rise, Glaciers and Rejuvenated Rivers Sculpture Them and Provide Habitats with Contrasting Exposures
    VOL. 53, 1965 BOTANY: J. CLAUSEN 1315 or parallel position. Plastocyanin is thought to function after the second light reaction and before cytochrome f. We thank Prof. A. Trebst for his many helpful comments, for providing us with his most recent results, and for supplying samples of DAD. Abbreviations: NADP, nicotinamide adenine dinucleotide phosphate; ATP, adenosine tri- phosphate; DAD, 2,3,5,6-tetramethyl-p-phenylenediamine; TMPD, N,N,N',N'-tetramethyl-p- phenylenediamine. * Dr. Urbach's work was supported by a fellowship from the Charles F. Kettering Foundation. 1 de Kouchkovsky, Y., and D. C. Fork, these PROCEEDINGS, 52, 232 (1964). 2 Trebst, A., Z. Naturforsch., 18b, 817 (1964). 3 Trebst, A., and E. Pistorius, Z. Naturforsch., 20b, 143 (1965). 4 Duysens, L. N. M., Science, 120, 353 (1954). 5 Ibid., 121, 210 (1955). 6 Goedheer, J. C., Biochim. Biophys. Acta, 66, 61 (1963). MICROCLIMA TIC AND VEGETATIONAL CONTRASTS WITHIN A SUBALPINE VALLEY BY JENS CLAUSEN DEPARTMENT OF PLANT BIOLOGY, CARNEGIE INSTITUTION OF WASHINGTON, STANFORD, CALIFORNIA Read before the Academy April 28, 1965 Most high mountain systems in the world are geologically young, precipitous, and topographically varied. As the mountains rise, glaciers and rejuvenated rivers sculpture them and provide habitats with contrasting exposures. The plant habitats of such mountains constitute a climatic mosaic with highly contrasting temperature zones in close juxtaposition. An example of such a geologically active region is the Slate Creek Valley of the Harvey Monroe Hall Natural Area, Mono County, California, where the Timber- line transplant station of our department is located. It is a recently glaciated, subalpine valley with predominantly north- and south-facing steep slopes that range in altitude between 10,000 and nearly 13,000 feet (3000-4000 m).
    [Show full text]
  • Edgar Anderson, WH Camp and the Evolutionary
    Descended from Darwin Insights into the History of Evolutionary Studies, 1900–1970 Joe Cain and Michael Ruse, Editors American Philosophical Society Philadelphia • 2009 TRANSACTIONS of the AMERICAN PHILOSOPHICAL SOCIETY Held at Philadelphia For Promoting Useful Knowledge Volume 99, Part 1 Copyright © 2009 by the American Philosophical Society for its Transactions series, Volume 99. All rights reserved. ISBN: 978-1-60618-991-7 US ISSN: 0065-9746 Library of Congress Cataloging-in-Publication Data is available from the Library of Congress. Cain and Ruse. 2009. Descended from Darwin (Philadelphia: American Philosophical Society) Chapter 4 Biosystematics and the Origin of Species Edgar Anderson, W. H. Camp, and the Evolutionary Synthesis Kim Kleinman The very process of synthesis combines disparate elements into a coherent whole, making complex phenomena more comprehensible as we understand which factors are decisive and, as importantly, which ones less so. Synthesis is a powerful intellectual tool, a beacon that illuminates a wide swath of previously unrelated facts, theories, and even disciplines. In biology in the second quarter of the twentieth century, just such a synthesis between genetics and evolutionary theory flourished through the work of R. A. Fisher, Sewall Wright, J. B. S. Haldane, Theodosius Dobzhansky, Ernst Mayr, George Gaylord Simpson, and many, many others. In addition to his crucial scientific work, Mayr made an invaluable organizational contribution through the Society for the Study of Evolution and its journal Evolution
    [Show full text]
  • Handbook of Neuroethics
    Handbook of Neuroethics Jens Clausen • Neil Levy Editors Handbook of Neuroethics With 31 Figures and 11 Tables Editors Jens Clausen Institute for Ethics and History of Medicine University of Tubingen€ Tubingen,€ Germany Neil Levy The Florey Institute of Neuroscience and Mental Health University of Melbourne Parkville, Australia ISBN 978-94-007-4706-7 978-94-007-4707-4 (eBook) ISBN Bundle 978-94-007-4708-1 (print and electronic bundle) DOI 10.1007/978-94-007-4707-4 Springer Dordrecht Heidelberg New York London Library of Congress Control Number: 2014946229 # Springer Science+Business Media Dordrecht 2015 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmissionor information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc.
    [Show full text]
  • Mongrels and Hybrids: the Problem of "Race" in the Botanical World Vassiliki Betty Smocovitis
    Mongrels and Hybrids: The Problem of "Race" in the Botanical World Vassiliki Betty Smocovitis My difficulty probably is that I do not know the exact meaning ofwords like species, speciation, populations, reproductive isolation, allopatric and sympatric speciation, geographic and ecological isolation as applied in your paper. IfI am wrong in my interpretation ofthem would you therefore kindly correct me. 1 must confess that I always have difficulties in reading papers discussing terminology, for I have in mind that the living world does not lend itself too well in our rigid classifications. I feel therefore that all kinds oftransitions exist between sympatric and allopatric distribution as well as between different kinds ofspecies. Scientific progress has often been delayed by a premature freezing ofour concepts into a terminology that hinders our clear thinking. -Jens Clausen, botanist, writing to Ernst Mayr, zoologist l The problem ofrace hasn'tfigured prominently in the entire biological world. In the plant world, for example, it rarely figures at all. What does figure, especially since Darwin first noticed it, is the deeper problem ofvariation. What it is, its origin, its maintenance and preservation (or its heritability), its pattern (continuous or discontinuous), and ultimately what biological purpose or function it serves does matter greatly. Common sense would tell us that if organisms were in fact adapted to suit their environments, then we would expect to find perfectly adopted forms, not all kinds and manners ofendless variability. The fact of the matter is that the problem of variation has been at the heart ofevolutionary thinking, yet few historians ofevolution have directly studied it.
    [Show full text]
  • Special Collections Department University of California Shields Library Davis, California
    Special Collections Department University of California Shields Library Davis, California An Oral History The Life and Work of GEORGE LEDYARD STEBBINS, JR An Interview Conducted By Mary Mead 1993 INTERVIEW CONTENTS Session 1, 23 June 1993. ............1 Early years: parents, ancestors; Mother's illness, 1915; private schools; interests and activities; Edgar Wherry University years: Harvard; summers at Seal Harbor; a major in biology and botany; Merritt Fernald, Edward Jeffrey; Oakes Ames; Karl Sax; personal interests in botany; graduate school; thesis advisors; problems with thesis; teaching assistantship; graduation, 1931 Post-graduate work: a position at Colgate University, 1931; research undertaken; A. P. Saunders Session 2, 30 June 1993. ..................17 Teaching and research: theory of evolution in 1920s; Darwin and Malthus; research at Colgate on peonies; Edgar Anderson; Sydney Blake; Antennaria; years during the Depression; an overall view of years at Harvard Marriage and familp: marriage to Margaret Godsborough Chamberlaine, 1931; children University of' California at Berkeley: a move to California; work with Ernest Babcock, 1935; Crepis; assistant professorship; Jens Clausen and the Biosystematists at Stanford, 1937 Session 3, 7 July 1993 ...........-32 Berkeley years: Biosystematists; Theodosius Dobzhansky; assistant professorship in genetics, 1939; organic evolution; advising graduate students; colleagues at Berkeley; Claude Hutchison; Erharta, Elymus, Dactylis; Mildred Mathias; Barbara McClintock; Daniel Axelrod; Carl Epling Transfer to UC Davis: establishing the Genetics Department at Davis, 1950; a field trip and a new species Session 4, 14 July1993. ..................59 Years at Davis: master plan for Davis in genetics; meets Barbara Brumley Monaghan, 1955; Me1 Green and Drosophila; teaching genetics; advising graduate students; California perennial grasses research; Guggenheim fellowship, 1961; developmental genetics--awned and hooded barley with Ezra Yagil, Vimal Gupta Session 5, 11August1993.
    [Show full text]