Systematics of Insects
and Arachnids
Status, Problems, and Needs in North America
Carl W. Schaefer and Michael Kosztarab
S
cholars in any active field ought to pause from time to time and take stock.
What have we learned? What do we know, and how much more should we
know? Of what knowledge can we reasonably be certain, and of what ignorance
can we reasonably be sure?
Now, at the start of the not-so-gay Nineties, and after more than a century of
work, entomologists may profitably take stock of what we know, and what we
ought to know, about the North American insect and arachnid fauna. Two swelling
streams-taxonomy and the recognition of habitat loss-once separate, are beginning to flow together. Their confluence and joined strengths will influence systematic
entomology certainly through the end of this millennium and well into the next.
Taxonomy (the describing, naming, and categorizing of organisms) and especially
systematics (the study of organisms' phylogenetic relationships) (Mayr 1969, Scudder 1987) have matured in the past few decades, both conceptually and technologically. The ideas of "species," and of the means by which they originate, have
enriched biology. Cladistic theory has become the unifying concept in systematics,
and increasingly useful and sophisticated algorithms permit the application (with
increasingly available computers) of the concept to ever larger and more recalcitrant
collections of taxonomic data.
At the same time, biologists and the public in general have begun to notice the
browning and the drabbing of the earth. Human populations increase dramatically;
so do the resulting pollution and the natural habitats laid bare. Much biological
diversity has been lost and is being lost; and we do not know what of value has
been lost with it. What species useful in better understanding ecological, phylogenetic, and biogeographical relationships are gone? What species of potentially
economic value can never be utilized? To know what we are losing, and thus to
preserve what we have, we must discover what we know of our remaining flora
and fauna, and estimate what we do not yet know. We must do more than decry
the loss of diversity. We must take stock, that we may use more productively what
is left to us.
Winter 1991
211
Our ability to take stock has been enhanced by the first stream, which itself has
been swelled by the increased interest in sampling the diminishing biota (especially
in the tropics): specimens gathered from threatened regions, in the biological equivalent of salvage archeology. Increased taxonomic and systematic abilities, and an
increased awareness that we are losing diversity, combine to make urgent an assessment of our taxonomic knowledge about all regions (see also Wheeler [1990]).
Much of the interest in "salvage taxonomy" has been concentrated (although
not equally) in the tropics, at once more biologically diverse, less known, and more
threatened than the temperate regions. Yet, precisely because they are better known
and less diverse, the temperate regions are more amenable to a stock-taking. And
surely, discovering what we know about one pan of the world must aid similar
work in others. After all, "Today's studies of the tropical fauna rely upon a taxonomic base established over the centuries by systematists working mostly with
temperate fauna" (Kosztarab & Schaefer 1990, 1-4); knowledge and interest are
not regional, not parochial. Assessment and understanding of the temperate fauna
should stimulate interest in all faunas, and both deepen and enrich our knowledge
of the tropical ones. The more we learn about one fauna, the more learning we
have to apply to others.
In this spirit and belief, two symposia were held in 1988, and the results published
in 1990 (Kosztarab & Schaefer 1990). Some thiny-two authors, aided by at least
250 other Nonh American taxonomists and systematists, considered the status of
our knowledge of the eleven arachnid and the thiny-four insect orders represented
in North America north of Mexico. The most imponant questions these authors
asked, and a summary of the answers, may be seen in table 1. Much of what follows
is taken from the conclusions of the published symposia (Kosztarab & Schaefer
1990,241-247), as is table 1 itself.
These authorities estimate that, overall, about half (52 percent) the insects and
arachnids of Nonh America have been described (table 1). If one excludes Acarina
(17 percent described), then about 60-67 percent of the remainder have been
described. These undescribed species are not scattered at random across the continent. Most probably occur in particularly poorly collected regions, like the desert
and montane southwest, the Great Basin, and the Canadian prairies; and any specialist knows other regions awaiting exploration for a given group.
That only half of the entomofauna is described in a continent long settled, long
stable, and long studied, tells us at once how tiny a percentage of the fauna must
be known from any tropical region. Moreover, only one sex has been described
in about 50 percent of the known species, and the immature stages have been
described in only 1-2 percent (Kosztarab & Schaefer 1990, 241-247). These percentages must diminish for the tropical faunas proponionately as the percentage
diminishes for the tropical species described.
What, more specifically, do these numbers tell us of our knowledge of the
entomofauna? And what is required to improve it? Some 100,000 species of insects
and arachnids have been described from North America, and about the same
number, it is estimated, remains to be described. Only one sex has been described
of some 50,000 species, and the immature stages of only a handful (table 1). Let
us assume for the purposes of calculation an average of four immature stages per
species, and assume too that none has been described. What remains to be done
can be estimated, as follows:
l
200,000 (both sexes of 100,000) new species to be described
800,000 descriptions of four immature stages per species (for 100,000 already
described and 100,000 new species)
50,000 descriptions of the other sex in half of known species
1,050,000 total new descriptions needed
Already available are 150,000 descriptions (100,000 species plus 50 percent of the
"Diversityand Dynamicsof North AmericanInsectand ArachnidFauna,I and II." Held
at the annual meeting of the EntomologicalSocietyof America,Louisville,Kentucky,December 1988.
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213
other sex), or 8 percent of the estimated total (1,200,000). Unfortunately, some of
this 8 percent includes species so poorly described as to be unidentifiable.
Thus, more than 92 percent of the descriptions we should have, we in fact lack.
"These undescribed forms conceal from us a vast amount of information vital to
a better understanding of all aspects of entomology and other disciplines. How
accurate can our ideas be-on phylogeny, biogeography, ecology, and other areas
of study-if we know so scant a proportion of the insect and arachnid forms in
North America?" (Kosztarab & Schaefer 1990, 241-247). How effectively can we
control pest arthropods and exploit beneficial ones?
"There are at present only a few hund(ed persons in the United States who are
competent specialists of some of the insect and arachnid groups, and even fewer
in Canada. However, most workers teach at universities and work only part-time
in taxonomy. The number of professional positions in taxonomy is drastically
declining in North America. The acute shortage of replacements in insect systematics is illustrated in a recent study by J. D. Lattin (1984, personal communication).
Of a sample of 82 professors of systematics at U.S. universities, only 25 (30 percent)
had graduate students in training during 1984, and about half of those had only
one student working on problems in systematics. Seventeen of these 25 were full
professors within ten years of retirement. Although the need for identification of
organisms has increased, the available individuals to do the work has decreased
drastically during the past two decades. If adequate replacements in systematics are
not trained, studies in biodiversity will soon face a grave setback.
"The U.S. Department of Agriculture Systematic Entomology Laboratory provided an average of 25,000 identifications and other taxonomic services during each
of the past three years. This included processing more than 400,000 specimens.
During these three years taxonomists associated with the Laboratory detected 33
insect species new to the United States, including many pests. The need for their
services is well documented through the Laboratory's 100-year history. Unfortunately, with the reduced financial support the Laboratory receives today, and with
the reduction of its staff to 23 research and 2 service scientists, and with the real
possibility of reduction to 15 scientists within the next 5 years, it will not be able
to keep up with the increasing demands during the biodiversity crisis" (Kosztarab
& Schaefer 1990, 241-247).
How can we improve this sad situation? Unfortunately, not easily. We estimated
(Kosztarab & Schaefer 1990,241-247) that at least 525 scientists and 525 illustrators
would require ten years to produce the necessary 1,050,000 new descriptions and
illustrations. We based this estimate on an average of two hundred work days per
year, considering one species description" and the necessary accompanying illustrations to be the average daily output of one scientist and illustrator. At an annual
salary of $40,000, completing this work will cost at least $42 million annually. We
did not include salary increases through the ten-year period.
We also need more collecting and more ecological and distributional information
about our fauna. Here we should enlist the aid of amateur entomologists, at the
local and state levels. It is unfortunate, and strange, that we have far fewer such
enthusiasts than occur in Europe or Japan. Children love all living things, including
the most abundant ones; yet somehow, in North America, their elders teach them
that insects are bad (perhaps because North America is but recently settled by a
nonindigenous population that has not yet come to terms with its environment
and therefore regards it with a subtle hostility). Local science fairs and 4-H programs
encourage children's interests, and entomological societies should as well. So should
all of us professional entomologists: how many of us take children on nature walks?
Write letters and popular articles for the local press? Urge our professional societies
to encourage young entomologists to work and even to publish field data and new
distributional records? We all should vigorously encourage and support the nonprofessional entomologists, for the increased knowledge they will provide, and for
the future development of our science.
In summary, the following recommendations were made from the two Entomological Society of America symposia (see Kosztarab & Schaefer [1990], 241247) to help remedy the present situation:
214
AMERICAN ENTOMOLOGIST
1. Let us make an all-out effort to employ in systematics research those who have
appropriate training but who are unemployed or underemployed at present, and
also to attract talented young scientists to taxonomic-systematic
work.
2. Let us provide broad enough graduate training to meet the challenges of the
twenty-first century in biosystematics, broaden the job opportunities at universities, and improve pay levels so they are attractive.
3. Systematists have to obtain more research grants for field work, faunal surveys,
and biosystematic revisions, as part of doctoral and postdoctoral research and
training, to be able to handle the backlog and to be able to reach the same
level of knowledge on insects and arachnids as their peers have already achieved
with the birds, mammals, and flowering plants in North America. The National
Science Foundation (NSF) and the Natural Sciences and Engineering Research
Council of Canada need to increase support for systematic work drastically.
Based on the grant list for taxonomic-systematic
projects of NSF, during 1987,
from the sixty-one awards for zoology, only fifteen (24 percent) were for insect
projects, including two for tropical studies. The proportion was not much better
in 1988, when of forty-five awards in zoology, only twelve (26.6 percent) were
for projects on insects, including two projects for tropical work and one for an
Australian survey. We did not consider one study that was funded basically for
molecular genetics, and one dissertation research grant.
Although insects and arachnids make up about 83 percent (100,349) of the
known animal species (120,955) in North America, they made up only about
25 percent of the zoology projects funded by the NSF Systematic Biology
Program in 1987 and 1988. This support share is even lower when we consider
the high percentage (48 percent) of undescribed species of insects and arachnids
in comparison with all other animals.
4. There is a need to collect, process, and curate the needed additional population
samples for a better understanding of biodiversity losses in North America.
Vacant museum or other curatorial positions should be refilled with taxonomists
to process the already accumulated and the incoming new population samples.
5. Systematists should strive to computerize present inventories of collections, and
make the records available to other users through an international entomology
collections network, to avoid duplication of efforts and materials and to save
on expenses.
6. We need to initiate more joint cooperative projects in biosystematics by
(a) contributing to the continent-wide projects of the Biosystematics Research
Centre of Agriculture Canada, initiated by L. Masner and his associates in
1987;
(b) coordinating state biological and natural history surveys and local experts
through a Biodiversity Center as suggested in the bill (HR 1268) last year,
and coordinating too with the Biological Survey of Canada (Terrestrial Arthropods) to expand into a continent-wide
biological survey;
(c) initiating more interdisciplinary efforts with ecologists, other biologists, and
systematists.
None of this is easy and some of it differs little from what those in other disciplines
seek: more workers, more resources. Taxonomists-systematists
need to make more
clear why and how their work is necessary to other biologists, conservationists,
land-planners, and all those concerned with local and global biotic diversity. Taxonomists-systematists
must make clear that their work is essential, not only in
providing identifications but (far more important) in providing the phylogenetic
bases-the
predictive bases-for
other biological work. And those bases rest upon
a deeper fundament: a knowledge and an understanding of biological diversity.
We urge further discussion of how our recommendations
might be made more
concrete and implemented. We urge professional organizations and societies to
discuss these recommendations
(and others) formally, in symposia and workshops.
And we insist that an effort to take stock and learn more about the North American
entomofauna
need not detract or distract from similar efforts elsewhere in the
world.
0
Winter 1991
215
Acknowledgment
We are very grateful to the Virginia Agricultural Experiment Station, Virginia Polytechnic
Institute and State University, and to G. L. Jubb, Jr., for permission to quote extensively
from "Systematics of North American Insects and Arachnids: Status and Needs" and to
reprint table 1 (with some minor modifications).
References
Kosztarab, M. & C. W. Schaefer [eds.]. 1990. Systematics of North American insects and
arachnids: status and needs. Virginia Polytechnic Institute and State University, Virginia
Agricultural Experiment Station Information Series 90-1, Blacksburg.
Mayr, E. 1969. Principles of systematic zoology. McGraw-Hill, New York.
Scudder, G.G.E. 1987. The next 35 years: invertebrate systematics. Can. J. Zoo\. 65: 786793.
Wheeler, Q. D. 1990. Insect diversity and cladistic constraints. Ann. Entomo\. Soc. Am.
Cited
83: 1031-1047.
Carl W. Schaefer received his bachelor of arts degree from Oberlin College and
his doctorate from the University of Connecticut. He studies the comparative
morphology and biology, and the phylogenetic relationships, of the land bugs
(Hemiptera-Heteroptera),
and is co-editor of Annals of the Entomological
Society
of America. He is professor of biology at the University of Connecticut, U-43,
Storrs, Connecticut 06269-3043. Michael Kosztarab received his bachelor of science degree from the Hungarian University of Agricultural Sciences and his doctorate from Ohio State University. His professional career focuses on the classification and biology of the scale insects. He currently is professor of systematic
entomology and founding director of the Museum of Natural History at Virginia
Polytechnic Institute and State University, Blacksburg, Virginia 24061-0319.
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