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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TWO
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-
PAGE
THREE
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
PAGE
FOUR
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.
PAGE
FIVE
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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SIX
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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SEVEN
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
PAGE
EIGHT
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
-
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.
-
Nigrelli, R. F. ed. 19-57. Modern ideas on spontaneous generation. Ann.
N. Y. Acad. Sci. 69: 255-376.
-
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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