Plant Science Bulletin archive

Issue: 1959 v5 No 3 FallActions

PLANT SCIENCE BULLETIN

A Publication of the Botanical Society of America, Inc.

VOLUME 5   JULY, 1959   NUMBER 3

 

Plant Science Bulletin

HARRIET B. CREIGHTON, Editor
Department of Botany and Bacteriology

Wellesley College, Wellesley 81, Massachusetts

EDITORIAL BOARD

George S. Avery, Jr    Brooklyn Botanic Garden

Harlan P. Banks    Cornell University

Harriet B. Creighton    Wellesley College

Sydney S. Greenfield    Rutgers University

Paul B. Sears    Yale University

JULY, 1959   •   VOLUME 5, NO. 3

CHANGES OF ADDRESS: Notify the Treasurer of the Botanical Society of America, Inc., Dr. A. J. Sharp, Botany Department, University of Tennessee, Knoxville 16, Tennessee.

Subscriptions for Libraries and Persons not Members of the Botanical Society: Send Orders or Checks made out to the Society to the Treasurer.

An Appraisal of Present and Future Trends in Botany*
By WILLIAM CAMPBELL STEERE

My consideration of present trends in Botany, leading to some crystal-ball gazing into the future, has been rendered immeasurably easier by my close association with the series of special papers published in the American Journal of Botany. Celebrating the fiftieth anniversary of the Botanical Society of America, these papers, reinforced by three additional ones, recently appeared in book form under the title, "Fifty Years of Botany." After living—and sleeping—with these papers for over two years, in reading each of them in manuscript one or more times, and in reading them again and again in galley and page proofs, I have nearly committed to memory the views and the ideas of the forty-some authors—which will explain my frequent reference to them.

The renaissance in taxonomy during the last decade or so—the "New Systematics"—has resulted from the transfusion into classical taxonomy of the data and the techniques of many other fields, as, for example, cytology, genetics, physiology, anatomy, ecology, experimental morphology, geography, biochemistry and biophysics. Thanks to wise and generous aid from the National Science Foundation, as well as from other agencies, and the dynamic approach of outstanding systematists to their problems, systematic biology is in better health than it has been for decades. Much thought and attention have been given to the philosophical basis of systematic biology by some of the best biologists of the present generation—Anderson, Clausen, Dobzhansky, Huxley, Mayr, Simpson and Stebbins, among others—and I commend their highly literate writings to you.

The very great importance of systematics in modern science has been emphasized recently by the "Report of the Committee on Systematic Biology of the American Institute of Biological Sciences" (1957) prepared at the request of the Divisional Committee for Biological and Medical Sciences of the National Science Foundation. Largely the work of the chairman, Ernst Mayr, this report states: "It should not be forgotten that the field of systematic biology continues to make important conceptual contributions to the field of biology as a whole. The great evolutionists, like Lamarck and Darwin, were practicing taxonomists and have them-selves attributed their concepts to this background. One

* This paper, one of three invitational addresses, was presented at a special symposium of the Botanical Society of America, at the meetings of the American Institute of Biological Sciences, at Indiana University, August 26, 1958. of the most important concepts in modern biology, that of the population, has grown out of the experience of practicing taxonomists. A healthy field of systematic biology is a necessity for the balanced development of biology as a whole."

Simpson (1945) summarized the situation very well, too, as follows: "Taxonomy is at the same time the most elementary and the most inclusive part of biology, most elementary because organisms cannot be discussed or treated in a scientific way until some taxonomy has been achieved, and most inclusive be-cause taxonomy in its various guises and branches gathers together, utilizes, summarizes and implements everything that is known about organisms, whether morphological, physiological, psychological, or ecological." The unifying force of systematics in the fields of botany and zoology gives it a transcendental importance as yet too little recognized. Further emphasis has been placed on the significance of plant systematics to the whole field of Botany, as well as the permanent value of good systematic work, in the excellent recent reviews by Constance (1955, 1958) and by Rollins (1958).

Like systematic botany, plant morphology has also experienced radical changes in its approaches and techniques. Eames (1958) presented an excellent resume of the remarkable progress in the field of morphology during the past five decades. He emphasizes especially the increasing importance of anatomy in the interpretation of form, in the development of theories of phylogenetic relationships, in the recognition of the polyphyletic origins of ferns and their allies, of conifers, and of flowering plants, and in many other new observations and theories that have revolutionized our understanding of the phylogeny of higher plants. The change in morphology from a rather narrow descriptive field fifty years ago to its present broad, interpretative and comparative status is clearly depicted by Eames, as follows: "The development of comparative study produced new bases for interpretation: the recognition that sound morphology must deal with the entire plant body, with vegetable as well as reproductive parts, with internal as well as external structures; the recognition that simplicity may represent reduction from complexity as well as primitiveness; that parallel and convergent evolution have played an important part in evolutionary modification; that evidence of these changes is as often hidden as obvious and must be obtained from as many fields of

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research as possible—not from morphology alone, but from taxonomy, cytology, genetics, geography, paleobotany, serology and other fields."

I have selected my quotations from Barnes, Mayr and Simpson especially carefully in order that each one might illustrate, and all might emphasize cumulatively, the only direction in which systematic and morphological botany can proceed successfully—through the use of all available data from every field of botany or biology, and through the development of broader research interests by individual investigators. To quote further from Mayr (1957) : "Much of the raw material for evolutionary studies, ecology, biogeography, and population work is supplied by systematics. Indeed, most of the modern workers are simultaneously taxonomists and workers in the stated fields. Some of the best work done in these borderline fields is done by systematists and is the result of painstaking taxonomic analyses."

Examination of the 40 papers comprising the Golden Jubilee Volume of the Botanical Society of America, "Fifty Years of Botany," will show mastery of more than one field by most authors, and the drawing upon several fields by nearly all authors. In other words, it is obvious that our better botanists, as well as our better taxonomists, must be versatile people with broad interests.

Ledyard Stebbins has reviewed the remarkable upheaval that took place recently in the classification of the grass family through new and significant data sup-plied by the microscopic anatomy of the leaf epidermis, the number and size of chromosomes, the comparative sensitivity to herbicides, the nature of the seed and its embryo, the developmental pattern of root hairs, the ecological requirements, and other characters of the plants ignored until recently. Needless to say, parallel investigations on other large and complex families will certainly result in equally revolutionary discoveries.

Edgar Anderson, in his inimitable style, has pointed out the necessity of developing logical basic procedures in those fields, such as taxonomy, where natural history, statistics and applied mathematics may come together. Through his own brilliant invention, the pictorialized scatter diagram, we have a relatively simple, precise, semi-graphical and semi-mathematical technique for dealing with multiple-sense-impression problems. The recognition of patterns and the development of techniques for handling pattern data, although essential to taxonomy, are much less related to statistics and statistical techniques than most biologists realize. In Anderson's opinion, real danger exists in using concepts based upon randomness in what he considers to be a highly non-random universe.

Other and perhaps more familiar examples of the inter-relationships between morphology, taxonomy, and physiology are easy to find. The differences between populations—whether varieties, subspecies, or species—of all plants and animals are important not only in taxonomic terms, but also in the most fundamental biological terms. These differences are expressed by every single aspect of the organism, by its metabolism as well as by its structure. Physiological and biochemical differences are well illustrated by closely related poisonous and edible species of mushrooms in the same genus, by the different aromas and flavors of fruits of closely related species and cultivars of higher plants, and by the difference in color of flowers, not rarely con-trolled by genetic inheritance of some factor that deter-mines the pH of cell sap. A fuller knowledge of the comparative biochemistry of alkaloids, saponines, volatile oils, carbohydrates, latexes, anthocyanins, flavones, and other common plant compounds will eventually be of the utmost importance to taxonomists, especially within closely-knit families and genera. It was no accident, for example, that systematic botanists were selected during 'World War II for the search for new and old sources of quinine, rubber and other strategically important plant products, in South America.

As a result of the ubiquitous and sometimes remark-ably obvious physiological and biochemical differences between closely related species, the correct identification of experimental materials becomes all the more urgently important.

In the past, we have derived very considerable insight into phylogeny and evolutionary steps through rare and accidental abnormalities. A new approach now may be through artificially induced teratology, which can well open a whole new field of experimental taxonomy. The use of gibberellins to promote growth in plants that are genetically inhibited, and the use of herbicides to inhibit growth in plants that normally produce lush growth might very well expose hitherto hidden pathways of evolution.

As an administrator for many years in universities, in governmental agencies, and now in a botanical institution, I have become almost unduly sensitive on one question—What is the future of botany? Like all questions, this one has two sides: What is the future of botany, as such, and What is the future of botany in relation to—and in competition with—other sci-

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ences? With this background I would like to discuss briefly a few of the major problems of Botany—and yet without the intention of sounding unduly critical or pessimistic.

I have heard some talk of botanists' "traditional and almost pathological distrust of zoologists." This unfortunate and unnecessary attitude, combined with the trend toward greater and greater specialization in each field, could very well result in the dissolution of biology as a field. Fortunately, several antidotes exist. The American Institute of Biological Sciences exerts a strong positive force for the identification and maintenance of Biology as a united field, in competition with the physical sciences. The National Science Foundation, likewise, supports Biology rather than botany, zoology, microbiology, or other biological fields. We must cancel all the long-standing feuds between the experimental and the descriptive biologists, between the physiologists and the taxonomists, between the botanists and the zoologists, and establish ourselves as biologists, or at least as plant scientists who are willing to work diligently and sincerely with the zoologists to build firm foundations under the flag of Biology, at the moment an amorphous and almost defenseless area. The great present strength of the two major fields of physical sciences, chemistry and physics, stems directly from their homogeneity, their integrity, and their avoidance of the suicidal fragmentation into special fields that may well destroy botany and zoology. No matter what area he works in, a chemist or a physicist is still a chemist or a physicist—whether he be in industry, in government, in business, in teaching, or in pure research. Already we have seen the declaration of higher salaries for government employees in the fields of chemistry and physics, at the expense of the biological scientists, because of the unity and identification with a common cause of the physical scientists. How many of us, on the other hand, consider ourselves botanists—or better, from a strategic standpoint, as biologists? Contrariwise, how many of us prefer to declare ourselves as physiologists, biochemists, anatomists, morphologists, taxonomists, ecologists, etc., ad infinitum? As a crytogamic botanist, I must confess that the specialists in lower plants are the worst of all in the scatteration and fractionation of botany, so that we have a plethora of societies and journals in this country and abroad dedicated to algae, fungi, bryophytes, or ferns, all of which develop a more general orientation toward Botany. The now defunct journal Hedwigia, published in Germany for more than a half century, served to bring together papers in all areas of crytogamic botany. Among its other casualties, World War II unfortunately brought about the demise of Hedwigia—but further and less conspicuous reasons may have been present, since an American journal of cryptogamic botany, Harvard's Farlowia, has also disappeared from the botanical scene.

Just in order to maintain their existence and to make any forward progress as a group, botanists are going to have to make an agonizing reappraisal of their attitudes, their loyalties, and their aims. Too many of our present attitudes are based on weakness rather than on strength—on insecurities, jealousies and on defense mechanisms—so that the enemy is within rather than without. Let's assume positive rather than negative attitudes, as difficult as this may be. I will make the prediction now that botantists will learn to pull together, through need if not desire, in order to protect the status and the prestige of their discipline.

Equal in importance to the selection of the problem is the nature of the written report that presents the results of the research. To some degree, morphologists and systematists are their own worst enemies. The charge leveled against them by workers in other areas, that their writings tend to be dull and prosaic, has more than a modicum of truth, most unfortunately. How many authors plunge into the description of a new species, a listing of well-known ones, or a minutely detailed analysis of a shoot apex without consideration for colleagues in other fields. A brief statement out-lining the need for the study, its relationship to other work and to other fields, or the underlying idea or principle, can make a paper intelligible to a reader whose specialty lies elsewhere, and can thereby stimulate latent interest instead of destroying it. Without doubt, the present-day high costs of publication and the consequent page limitations enforced by most botanical journals constitute one factor in the production of a near neurosis in many authors who have developed a cold, sterile, telegraphic style that keeps the reader at arms length, if not farther. During my years as editor of the American Journal of Botany, and as dean of a graduate school, I was shocked by the rarity of manuscripts or dissertations that I could read with pleasure or even with sustained interest. I take this as a golden opportunity to point out to the younger botanists that no author should feel apologetic for the occasional use of "I," and that without being either verbose or chatty, and still more important, without reducing accuracy, an author can by the subtle introduction of his own personality into his writing establish rapport with the reader and thereby stimulate his interest. Clear and emphatic writing will become increasingly necessary in a not distant future in which all papers reporting original research and ideas will be abstracted into electronic "memories." On receipt of the proper code or other stimulus, these devices will be able to "recall" and to retrieve all available information on any topic that has been fed into them. Consequently, the sharp and clear identification of topics and ideas, although helpful now, will eventually become essential.

That the teaching of botany in high schools and colleges requires some reforms is certainly an understatement. The basic problems seems to be that Botany is too generally taught as if every student were preparing himself to enter the professional field of plant science. Instead of giving general students the basic information on what plants are and how they function, too many

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teachers and texts submerge them in a welter of details and of terminology that serves to alienate the student instead of fascinating him. The man-hours spent in defining and clarifying the problem in the annual meetings of the Teaching Section of the Botanical Society of America have by no means solved it. The eloquent and forthright articles by Cox and Behnke, by Fuller, by Peattie and by Hylander in "Fifty Years of Botany," and by these and other botanists elsewhere may eventually lead to greater awareness of the desperate need to stress plants in the teaching of botany, as absurdly obvious as this may seem. Botanists have been increasingly active and increasingly articulate about course content and curriculum, both at the high-school and the college level. The Committee on Educational Policies of the Biology Council of the National Academy of Sciences—National Research Council, and the National Committee and Program for the Study of the Curriculum in Biological Sciences furnish excellent evidence of the national awareness of this problem.t

The modern trend toward more and more collaboration between fields, and the success of research in those areas where different fields come together have produced a concomitant need for broader training for under-graduate and graduate students in botany, even for those planning to enter the more traditional areas. If I may interject a personal note, my plan on entering college to prepare myself as a biochemist (or physiological chemist, in those far-off days), my eventual graduation as a plant physiologist, and my doctoral work in cytology, have combined to give me an extremely helpful background for subsequent research in plant geography, ecology and systematics. Taxonomists and ecologists of tomorrow will need, more and more, the quantitative tools derived from statistics, applied mathematics, and the use of computers as so clearly set forth by Edgar Anderson.

With the astonishingly rapid development of electronic devices for the storage and transmission of information, I predict that within a relatively short time much of the drudgery and housekeeping work of systematic botanists will be relegated to electronic computers. With a technical assistant to feed information into a machine, the routine identification of materials submitted for identification will be enormously simplified, as the machine will either furnish one or several possibilities, of which the correct one may then be determined by comparison with specimens or illustrations, or the specimen in question can be televised over a closed system to a national identification service, where skilled technicians can give the correct answer. Unfortunately, much of the routine and time-consuming labor of botany has been confused with research.

As has been pointed out by so many biologists during the past decade, systematic biology is an extremely complex field that ranges all the way from the initial inventory of plants or animals of a little-known area, with emphasis on new species, to the extremely sophisticated experimental study of the structure and origin of species. Pioneer work in new regions is urgently important, of course, because plant species are being destroyed in large numbers through the inroads of agriculture, fire, and the depredations of goats, rabbits, and man. Hundreds of species of plants have disappeared from the face of the earth without leaving a trace be-hind, just since the turn of the century, when modern collecting methods were already well established. Fortunately, in some remote areas, for example the Philip-pine Islands, dedicated workers, as E. D. Merrill, whom Frans Verdoorn termed the "New Linnaeus," were hard at work, and the spirit of exploratory botany still burns brightly in a few institutions. The modern and certainly the future trend in systematic botany is toward the so-called biosystematic approach to plant taxonomy. One of the real pioneers in this field was Harvey M. Hall, who brought his work to a spectacularly successful beginning at the Carnegie Institution of Washington's Biological Laboratory on the Stanford University Campus, with the aid of an outstanding team consisting of Jens Clausen, David D. Keck, and William M. Hiesey. The death of Hall, the move of Keck to The New York Botanical Garden, and the recent retirement of Clausen have combined to slow up the brilliant biosystematic work of a gifted team. However, it is very safe to predict that this sort of work, comprehending ecological, morphological, genetical and cytological data, is certain to continue on an increasing scale.

The somewhat too completely accidental nature of the choice of central interest of any given taxonomist in any institution is an accepted American tradition. Al-though we assume that, in a democratic culture, every systematist has the privilege of choosing his own area of specialization, we do run the very real danger that some or many groups of plants, purely by chance, will not be elected for active research. As a consequence of our democratic system, many groups of plants remain relatively unknown and cannot be identified with any certainty. In the event of a sudden rise to economic or strategic importance of any of these numerous unstudied groups, we might find ourselves confronted with a national emergency. Consequently, a somewhat more regimented approach may have to be taken—the National Science Foundation, the United States National Museum, or some other national agency may have to put a premium on the study of little known groups of plants in order that we may have not only specialists but, much more important, positions covering all groups of plants. It is possible that we may eventually develop a National Identification Service.

I predict that taxonomists will gain much insight into evolution and genetic fluctuations through the effects of controlled and accidental radiation. Taxonomists will certainly be called upon to identify plants

t Subcommittee on College Education of the Committee on Education Policies. 1957. Improving College Biology Teaching. Biology Council, National Academy of Sciences—National Research Council Publication 505. 70 pages. Washington, D.C.

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that seem to indicate uranium-bearing rocks or soils—in fact geobotany is already a well-established field. However, the recognition of plants that are unsually sensitive or unusually resistant to excessive radiation is still in the future. It will not be long before we will need to know which plants may serve as indicators of accumulating fall-out dusts and particles.

Our best approach to the manning of all our research strength may perhaps appear to be somewhat bureaucratic, and yet can be accomplished without real regimentation. The establishment of research professor-ships or research curatorships is certain to attract strong and dedicated workers. In a thoughtful address before the AAAS, Dr. Glen T. Seaborg stressed the enormous importance of science in the present and future development of America. Among many significant suggestions and recommendations, he said, "I believe we need to establish more research professorships so that outstanding research scientists who may not be needed or suited for formal teaching are able to assist in the training of graduate students." In addition to their training function, research professorships also serve the very important and obvious purpose of increasing the rate and productivity in basic research. One of the most significant steps to be taken in this direction is the establishment by the American Heart Association of lifetime grants to medical scientists for the rest of their productive life, covering salary at a generous level, travel, technical assistance, and other necessities of professional productivity. Called "Career Investigator-ships," these grants are "intended to foster unrestricted research of a basic sort by relieving scientists of the strain of teaching, the distractions of administration, and the time-consuming and often vain pursuit of short-term aid." I cite this magnificent example at some length as an ideal for systematic botanists to strive for, and for our eventual achievement of a full coverage nationally of all taxonomic groups.

I predict that privately and publicly supported botanical institutions will gain increasing momentum in basic systematic research. The immense prestige and influence of the Buitenzorg (now Bogor) Botanical Garden in Java for nearly a century as a source of morphological and taxonomic research materials is obvious from even a casual reference of the literature. The increased emphasis on botanic gardens in the last decade is encouraging, as through these institutions a broader base of public support of botany can be obtained. The brilliant success of the Los Angeles State and County Arboretum is a direct result of the guiding genius of Frits Went, for whom I can predict a still greater success at the St. Louis Botanical Garden. George Avery has made a great public relations success for botany at the Brooklyn Botanic Garden, that reflects much to his personal credit. The Boyce-Thompson Institute, The New York Botanical Garden, the Chicago Natural History Museum, the California Academy of Science, the great botanical gardens in London, Berlin, Paris, Copenhagen, Stockholm, Leningrad, and elsewhere in Europe, in Singapore, Borneo, Trinidad, Rio de Janeiro, Jamaica, West Africa, and elsewhere in the tropics, are all important as primary loci for basic research or as sources for research material.

I predict the development of even larger and more accurately planned phytotrons, after the pioneer developments of Frits Went. With these facilities that may duplicate all the climates of the world, experimental ecologists, taxonomists, morphologists and physiologists can test the innate variability and nature of plant materials.

I predict that paleobotany, through the development of more refined techniques and the exploration of new and rich deposits will reveal plant materials perfectly fascinating to morphologists, systematists and geologists. The field of micropaleontology is in especial need of expansion by botanists.

Although exploited and unfortunately somewhat discredited more than forty years ago, the field of serum diagnosis, for determining the degree of relationship of organisms and groups of organisms, is entering a new phase, in which the results are more important than the justification of the techniques. Through varied biochemical and biophysical techniques, ranging from chromatography to electrophoresis, the proteins and sera of plants and animals are being studied and compared at an ever increasing rate. I predict positive and enlightening results from these techniques that can be almost immediately applied to the solution of some of our numerous and perplexing problems of plant phylogeny.

Although almost a stepchild of botany a generation ago, ecology has come of age and is now a welcome and important member of the family. Among the most significant contributions of ecology, in my estimation, was Chaney's application of the philosophy of associations to paleobotany and thereby clarifying the identification of many previously unknown members of several geological horizons. The detailed studies of plant associations in the Brazilian rain-forest by Cain and his co-workers, in "Fifty Years of Botany," will long remain a classic of its kind, we may be very sure.

I foresee that many relatively or totally new phenomena will receive study by botanists. Carbon-14 is a magnificent indicator of the past, and through its determination, accurate estimates can be made of plant migrations and post-Pleistocene plant history. The ecological and phytogeographic significance of this technique has hardly been touched.

Permafrost, or permanently frozen ground, is a little known, little recognized, phenomenon of arctic regions, little studied by botanists, yet has a pervasive influence on the distribution of plants and animals. I predict a much greater emphasis in botanical research on the implications of permafrost, especially in view of our uneasy but inevitable preoccupation with north-ern regions.

One of the bright spots in the future of the various areas of systematic botany, plant morphology, phytogeography, ecology, paleobotany, is the valiant effort

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of the National Science Foundation to support basic research. While plant physiology, biochemistry and genetics derive support from a dozen or more private and governmental agencies, the so-called "descriptive" areas remain without adequate support, illustrating too well the fact that even within the boundaries of science one may find "have" and "have-not" fields. The prospect of ever increasing financial support for research of a basic nature in our "have-not" areas is encouraging indeed.

One of the concomitant features of greater support of the at-the-moment less glamorous areas of botany is an increase in prestige of these areas and the easier recruitment of graduate students in them. At present, too many of our abler graduate students are attracted by more spectacular and more remunerative fields of botany, and even more, of course, by the physical sciences and engineering.

In spite of the pessimism of some of my remarks. I conclude that the future of Botany is very bright in-deed. If you think I say this in any offhand or casual manner, I must remind you that I have recently dedicated the remainder of my professional life to what I consider to be the best interests of botany, and with the intention of devoting my full energies to this field. Only history will supply a brief foot-note on the wisdom of my decision?

Some Questions About "One Teacher's Questions About Textbooks"
JOHN A. BEHNKE, The Ronald Press Company

Much of what "One Teacher" (P.S.B. Vol. 4, No. 4) says many publishers would agree with. Textbooks could and should be better—and so should students and teachers. Aren't the textbooks products of the courses taught and the people who teach them?

Some of the comments made by Dr. Creighton would not apply to the great majority of cases, and some of them are of minor importance. Anyone who has seen the students trudge to the second-hand book dealer's stand at the end of the year has noted that the great bulk of the volumes they are carrying are not pristine new but have had hard use. Nor are all of these students loaded with misinformation from the books they have read. Haven't the best of the authors done at least as thorough a job of checking and thinking through the material presented as the average teacher?

But let's look at the more important issues. The critical point of the remarks on textbooks is the question of the impression of finality and completeness most texts convey. Again, is it the textbook alone that develops this theme or is it characteristic of most of the teaching? Each teacher likes to think he is teaching the scientific process (not, we hope, the non-existent "scientific method") , but is he doing it in practice? Would he use a book that raised controversial issues or developed in some detail the unsolved problems of his subject? The reception afforded the few books that have attempted this would not be very encouraging to the most public-spirited publisher.

Some of us hope that this situation will change. But to achieve substantial success would require the beginning of this teaching approach at a much earlier level than college. It could begin in the grade schools. When and if it becomes an integral part of the educational process, we can certainly expect textbooks to reflect it.

Perhaps the best answer to other points raised will be through a look at the four basic purposes the textbook may serve: 1) the imparting of factual information; 2) the development of principles and concepts; 3) the creating of interest and stimulation; and 4) the synthesis of a coherent whole.

The first purpose should be served in all textbooks, but often the amount of factual information included has been overwhelming. The reference type text is best suited to advanced courses where the student wants to know and should be expected to master detailed information of the field in question. The danger here is that the text may take the place of learning to use the original literature. Isn't it preferable to have the text serve as a launching pad to take off into the work of the experimental scientists as they have reported the facts them-selves? The elementary student is more likely to be bewildered and lost and ultimately repelled if he must merely memorize mountains of facts without real depth of understanding. The trend away from this approach would seem to be justified. On the other hand, a hard core of factual information is acquired more accurately and more efficiently from reading than from lectures. The information of the text should free the teacher to lecture on the significance, the interpretation and the conceptual framework of the facts.

However, to turn to point two, the facts presented in the text will have more meaning and will be better understood if related to a framework of principles. Nor need this theoretical structure rob the teacher of the opportunity of elaboration and elucidation of these unifying concepts.

Dr. Creighton fears that a lively stimulating approach will sabotage the efforts of the teacher to be lively and stimulating. Has any text ever presented all the interesting and challenging possibilities of its subject? If so, that field must have a paucity indeed. Fortunate is the student with at least an interesting textbook if he has a dull teacher. How much more blessed the student with an interesting text and a sparkling teacher. The latter is not unknown.

And lastly, but far from least, there is the coherence that can be achieved in most, if not all, subjects. Both text and lectures should strive to put the material together. But again, to see it and study it on the printed page can be more effective than listening to lectures and trying to piece the subject together from a set of notes.

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The place of illustrations in furthering these ends has been covered in the A.I.B.S. Bulletin, Vol. 7, No. 5, pp. 26-28, Nov. 1957. (Also available in reprint form from the Division of Biology and Agriculture, National Research Council, 2101 Constitution Ave., Washington 25, D.C.) .

In conclusion, I must agree with this "one teacher" that many texts fail to reach the ideal that has been out-lined here. However, there are many that come close. And when properly used by the effective teacher, they can contribute much to a good course. I have even known some textbooks that were seldom carried to the second-hand dealer because the students found them interesting enough and valuable enough to be added to a permanent library.

Evolution in Beginning Botany Courses - The Mid Twentieth - Century Dodo Bird?
EMANUEL D. RUDOLPH, Wellesley College

The centenary year of the publication of The Origin of Species seems a good time to take stock of the influence of evolutionary thinking on the way we teach elementary botany. If one judges from the treatments of evolution in the current beginning botany texts, it appears that the applications of evolutionary thought to botany are very limited, and although botanists believe in evolution few of them are really working on problems connected directly with plant evolution. Perhaps, it is that in the plant kingdom, unlike the animal kingdom, we do not find clear relationships among the larger divisions from the morphological and paleontological data. Perhaps, it is also the disillusionment with the "alternation of generations" key to the understanding of plant evolution which seems to unlock fewer and fewer doors as we learn more and more about cytogenetics and developmental morphology. Then too, we now place justifiably greater emphasis upon physiology and biochemistry in our botany teaching than did teachers fifty years ago. Do these reasons warrant the strong deemphasis given to careful consideration of evolution in general botany teaching? Are there ways in which evolution can be made a vital part of the beginning botany course?

No one would question the statement that evolutionary thinking is one of the most significant contributions of science to our cultural heritage or that it is one of the few important general unifying concepts in the biological sciences. Thus, does it not behoove us as teachers of botany to present, especially in our elementary courses, specific and up-to-date information about how evolutionary theory relates to plants? The problem then is, how can we present the available in-formation to the beginning student in a stimulating way and what types of modern information are there that are suited for presentation at this level of instruction?

The areas of botany which come to mind, and I am sure that you can think of some others, that are concerned with evolution are: paleobotany, morphology, cytogenetics, and systematics; plant geography; origin of cultivated plants; and origin of metabolic systems. It would seem from the textbooks that only through paleobotany have we and are we learning about plant evolution. Even in that area, where do we find consideration of such examples as the work of Florin (1951) on the evolution in the cordaites and conifers, or the work of Mamay and Andrews (1950) on the evolution of the fern leaf, or even the important telome theory of Zimmermann (1930, 1949; Wilson 1953) and its applications? It is perhaps true that these series are not as complete or as generally known or as striking as the Eohippus-horse series of the zoologists, but, with good illustrations, they could be as useable for teaching the principles of plant evolution as are the horses for teaching animal evolution. In the area of morphology, cytogenetics, and systematics, the Chlamydomonas-Volvox series in the algae is sometimes considered, but where is the abundant information of evolution in the flowering plants used for beginning students? Such work is summarized in the books of Stebbins (1950) and Good (1956) and some excellent and well illustrated examples are presented in the recent papers of Bailey (1944, 1953), Lewis (1953), Stebbins (1956) , and Iltis (1957). In the area of plant geography, fine illustrative material for a consideration of evolution by recent as well as fossil plant distributions can be found in the summary of Cain (1944) or in such papers as those of Marie-Victorin (1938), Du Rietz (1940), Li (1952), and Axelrod (1958). Cultivated plants, which after all were used by Darwin as one of the key evidences for evolution, offer some fine material for considerations of evolution; particularly the grains (Vavilov 1949-50, Schiemann 1932, Anderson 1952, and Mangelsdorf 1953, 1958).

The genetic origin and evolution of metabolic systems offer worthy exposition for the teacher with an evolutionary point of view. The induced changes of the enzyme systems in Neurospora (Beadle 1945, Horowitz 1950) and in bacteria (Lederberg 1956, Zinder 1958) as well as the problems of the evolution of these systems in the earliest forms of life (Oparin 1957, Nigrelli 1957) are fascinating subjects that could be used in teaching. These few examples can I am sure be multiplied by each of you with a little thought. There is ample evidence in recent botanical studies, some of which have been cited here, for an interest in evolution and its mode of action. Is it not our duty to present this current evolutionary thinking to the beginning students, most of whom will not be exposed to formal science teaching again?

As teachers, all that we really need is an evolutionary point of view that will induce us to search out and utilize the already available illustrated material in various botanical publications, be it only for a few species, a genus, or a group of plants. It should not really trouble

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us that we do not have completely documented information about the broader relationships in the plant kingdom. The value to the students of information about plant evolution, even if it is very incomplete—a prodding indication that botanists are still actively interested in and actively working on evolutionary problems—should be well worth the effort on our parts.

REFERENCES

  1. Anderson, E. 1952. Plants, Man and Life. Boston. 245 p.

2. Axelrod, D. I. 1958. Evolution of the Madro-Tertiary geoflora. Bot. Rev. 24: 433-509.

3. Bailey, I. W. 1944. The development of vessels in Angiosperms and its significance in morphological research. Amer. Jour. Bot. 31: 421-428.

4. 1953. Evolution of the tracheary tissue of land plants. ibid. 40: 4-8.

5. Beadle, G. W. 1945. Biochemical genetics. Chem. Rev. 37: 15-96.

6. Cain, S. 1944. Foundations of Plant Geography. New York. 556 p.

7. Du Rietz, G. E. 1940. Problems of bipolar plant distribution. Acta Phytogeog. Suecica 13: 215-282.

8. Florin, R. 1951. Evolution in Cordaites and conifers. Acta Horti Bergiani 15: 285-388.

9. Good, R. 1956. Features of Evolution in the Flowering Plants. London. 405 p.

10. Horowitz, N. H. 1950. Biochemical genetics of Neurospora. Advances in Genetics. 3: 33-71.

11. Iltis, H. H. 1957. Studies in the Capparidaceae III. Evolution and phylogeny of the western North American Cleomoideae. Ann. Mo. Bot. Gard. 44: 77-119.

12. Lederberg, J. 1956. Genetic transduction. Amer. Scientist. 44: 246-280.

13. Lewis, H. 1953. The mechanism of evolution in the genus Clarkia. Evolution 7: 1-20.

14. Li, H. -L. 1952. Floristic relationships between Eastern Asia and Eastern North America. Trans. Amer. Philos. Soc. 42: 371-429.

15. Mamay, S. H. Y3 H. N. Andrews 1950. A contribution to our knowledge of the anatomy of Botryopteris. Bull. Torr. Bot. Club 77: 462-494.

16. Mangelsdorf, P. C. 1953. Wheat. Sci. Amer. 189: 50-59.

17. 1958. Ancestor of corn. Science 128: 1313-1320.

18. Marie-Victoria, F. 1938. Phytogeographical problems of Eastern Canada. Amer. Midland Naturalist 19: 489-558.

  1. Nigrelli, R. F. ed. 19-57. Modern ideas on spontaneous generation. Ann. N. Y. Acad. Sci. 69: 255-376.

  1. Oparin, A. I. 1957. The Origin of Life on the Earth. 3 ed. New York. 495 p.

21. Schiemann, E. 1932. Entstehung der Kulturpflanzen. Handb. Vererbungswissensch. 3. Berlin. 377 p.

22. Stebbins, G. L. 1950. Variation and Evolution in Plants. New York. 643 p.

23. 1956. Cytogenetics and evolution of the grass family. Amer. Jour. Bot. 43: 890-905.

24. Vavilov, N. I. 1949-50. The Origin, Variation, Immunity and Breeding of Cultivated Plants. Chronica Botanica 13: 1-364.

25. Wilson, C. L. 1953. The telome theory. Bot. Rev. 19: 417-437.

26. Zimmermann, W. 1930. Die Phylogenie der Pflanzen. Jena. 452 p.

27. 1949. Geschichte der Pflanzen. Jena. 11 p.

28. Zinder, N. D. 1958. Transduction in Bacteria. Sci. Amer. 199: 38-44.

BRIGHTER BOTANY CORNER

Report on the promotion of growth of palm seedlings by an oil spray reminds us of the man who claimed he could always get action by greasing some palms.

Society Sponsored Summer Institutes

Most summer institutes for high school and college teachers, financed by the National Science Foundation are planned by a college or university. The staff in one or more departments, often joining with the department or school of Education make their plans, write up their application and submit it to the NSF. Most of the institutes have been for high school teachers because every-one, including Congress which makes the appropriations to the NSF, realized that there were many ambitious high school teachers who wanted to learn more about the subjects they teach, fill in gaps in their own under-graduate training, and bring themselves nearer up to date on facts and thinking. The National Science Foundation has always asked for funds to help to improve the teaching of the sciences in colleges, and Congress has appropriated some funds for this purpose.

The Botanical Society was one of the first societies to sponsor an Institute for college teachers, backing up an offer of Harlan P. Banks at Cornell to organize one for us. The germ of the idea came from the address in Gainesville of Retiring President Ralph Wetmore. For two summers the botany staff at Cornell did a service above and beyond the call of duty to put on Institutes which all who attended felt were of great value. There were more applicants than could be accommodated, leaving aside the awarding of stipends. Many who came once wanted to come again. One reason, but not the only one, was that the speakers who came for a week or two were excellent people and gave unstintingly of their time, energy and experience. And undoubtedly one reason these botanists came and did their best was that the project was sponsored by the Botanical Society. After two Institutes the department at Cornell quite rightly felt that they could not devote any more of their energy and time to Institutes and no other university offered to plan one, nor was there any obvious way for the Society to go about finding a university which could and would.

We should all be grateful that Indiana University's Botany Department under the leadership of Ralph Cleland is picking up the idea for this summer. We can hope that having learned the ropes they will be willing to help the Society again another year, and as long as they feel that they can. But sooner or later those individuals will feel that they must go back to their usual summer research, or other duties. It is none too soon for people at other universities to begin to see whether they would like to offer their facilities to the Society some summer. It looks as if the need for programs to help keep college botany teachers alerted to advances in research and changes in points of view will continue, in fact may increase. As long as there is a real, expressed need Congress will undoubtedly provide the money for NSF support. The Botanical Society, which was among the first of the biological societies to act, will want to continue to do its part in strengthening the teaching of botany for college students.

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