One useful definition of conservation is ‘the carrying of the maximum
genetic diversity into the next century’. If we accept this definition,
then it follows that we should be concerned for all groups of animals and
plants, not just for a few selected groups. In practice, however, conservationists
have tended to overlook invertebrates, while generally placing more emphasis
on vertebrates and vegetation. This is unfortunate, because an understanding
of invertebrate faunas could prove a very powerful weapon in conservation.

Most people now agree that the conservation of wildlife and other natural
resources is essential for the future of the planet. And yet, however strongly
one may feel about this, there are always many valid claims for land use
other than the conservation of natural resources. Since we shall continue
to need houses, roads, airports and so on, we are faced with a situation
in which our task is to be selective. We have to decide which areas are
more worthy of conservation than others, bearing in mind other legitimate
needs for land use.

The task of deciding what is to be saved and what is not must be based
on certain criteria, of which genetic diversity must be one. For example,
say we are faced with the need for an airport in a certain part of the country.
The precise locality does not matter very much, as long as it satisfies
certain basic requirements. In the end, a number of localities will be short-listed
and a decision will have to be made as to which will become the actual site
of the airport. This is where an understanding of the invertebrate fauna
might prove useful.

In Britain, Sites of Special Scientific Interest are usually designated
as such on the basis of an evaluation of the vegetation; furthermore, the
general botanical map of the British Isles is, on the whole, very well worked
out. In our airport example we will, therefore, be comparing sites whose
botanical diversity is well described. If we find ourselves in the situation
of having to decide between two botanically similar sites, say, two oak
woods, a survey of the invertebrates of both woods should go a long way
towards helping us to make a decision regarding which of the two woods it
would be best to conserve.

Of course, if one is to apply such a criterion, one must have the basic
information at one’s disposal. In the case of invertebrates, such information
is sadly lacking.

Surveys of the invertebrate fauna must be strictly comparable, using
identical sampling techniques, carried out under similar weather conditions
and over the same period of time. Work by Henry Disney, Dennis Unwin, myself
and others has shown that different trapping methods will result in a very
different pattern of insect diversity emerging during survey work of this
kind. It is important, therefore, to use a variety of sampling methods if
one is to obtain results that are a fair reflection of the actual diversity
of the site. The data must also be quantitative and replicated, so that
they can be defended with confidence; all too often in the past such surveys
have depended on anecdotal information of limited value. The importance
of ‘hard’ data cannot be overemphasised, since conclusions based on survey
work will have to be defended before policy-making committees, and possibly
also courts of law.

An important point to bear in mind is that, of two given sites, the
one with a greater diversity of plant life may not necessarily be the richer
in terms of invertebrate species diversity. For example, a forest with much
dead wood lying in it is likely to be fairly poor in ground flora, whereas
its invertebrate fauna is likely to be very rich. Furthermore, a survey
of invertebrates may well reflect other aspects of the site indirectly.
This is because invertebrates, especially insects, exhibit a great diversity
of life habits, including parasitism, predation, leaf-mining, gall-forming
and many others that depend on the presence of specific animal or plant
hosts. It is clear that, if a parasite exists in a given locality, its known
host must also exist, but the opposite is not necessarily true.

The species diversity of invertebrates is not, of course, the only aspect
of invertebrate biology which is of conservation interest. Invertebrates
form an important food source for very many vertebrate species, and hence
the biomass of invertebrates in a given locality is a matter of great importance.
Certain habitats may not support a great diversity of insect species, but
yet may have a great productivity of one or two important food species that
are essential for the survival of a threatened vertebrate species in the
area. For example, the very saline Mono Lake in California contains only
two species of invertebrates, a species of Artemia (a small crustacean)
and the larva of an ephydrid fly, Ephydra hians, and yet the adult flies,
which emerge in vast numbers, form the basic food source of an important
waterfowl fauna in the region.

Other criteria on which conservation policy decisions should be based
include rarity of species and ‘naturalness’, that is, the extent to which
the area has been left undisturbed by man. Invertebrates may be of use when
assessments are being made on the basis of these criteria, although with
our present limited knowledge of what constitutes a rare invertebrate, the
criterion of rarity is difficult to apply. However, there are a number of
successful cases on record where the criterion of naturalness has been successfully
applied on the basis of knowledge of the insects of ancient woodlands. The
naturalness of the history of sites has also been evaluated on the basis
of the remains of molluscs and some groups of insects preserved in soils.

The evaluation of sites of potential conservation interest by means
of invertebrate surveys is of great practical use. The cost involved is
low, the returns are quick, and yet are highly rigorous, since invertebrates
can be collected easily and in large, statistically significant numbers.
And yet one important impediment remains; our limited systematic knowledge
of many of the invertebrate groups involved. Despite heightened awareness
of the threats to the biodiversity of the planet, the scientific study of
that diversity, both for its own sake and for the sake of saving it from
extinction, remains a minority task which appears not to be recognised or
supported by the leading biological fund-awarding bodies. It is to be hoped
that this problem will be recognised before it is too late.

Zakaria Erzinclioglu works in the department of zoology at the University
of Cambridge.

By ‘zoology’, we mean such disciplines as herpetology, entomology, mammalogy,
taxonomy, ichthyology, palaeontology, ornithology, malacology and whole-animal
physiology, where the central emphasis is on the animal and its relationships
with other species and with the physical environment. For want of a better
term, we shall refer to research in such areas as ‘special zoology’, to
distinguish it from the work in ‘general zoology’ with which more and more
biologists are concerning themselves.

Thus, special zoology lies at the opposite pole of the biological spectrum
from general zoology, where the objective is to elucidate principles that
could be applied to any animal species, or to living things as a whole.
For example, biologists working on the function of chloride channels in
cells are not primarily concerned with the intrinsic interest of the species
they use as an experimental animal. They select their experimental animal
to satisfy certain pragmatic criteria, such as the ease with which it can
be grown in the laboratory, the ease with which it can be dissected, the
cost of maintenance, whether or not it expresses the phenomenon under investigation
in such a way as to make it easier to study, and so on. Such biologists
are not really concerned whether the animal is an axolotl or a lammergeier,
so long as it satisfies certain basic criteria. Thus, the fruit fly, Drosophila
melanogaster, became such an important tool in genetic research not because
geneticists found it intrinsically interesting, but because it was a ‘convenient’
organism to work with.

Special zoologists, on the other hand, are interested in their animal
regardless of whether it satisfies various practical criteria; they are
interested in a particular animal species, group of species, or even an
individual specimen, because of its intrinsic interest or applied importance
(for example, in relation to its role as a pest or vector). Where the focus
of attention is of intrinsic interest alone, the zoologist ignores the fact
that the subject might be inconvenient to study. Thus, palaeontologists
studying dinosaurs disregard the fact that they are rare, incomplete and
difficult to excavate; they study them because they find them intrinsically
interesting, while all the time believing that they might also reveal something
of widespread relevance in biology.

So how has the decline in special zoology come about? The reduction
in funding has, of course, coincided with the revolution in molecular biology
during the past 25 years or so. In terms of aims fulfilled, molecular biology
must rank as one of the most successful endeavours of modern science, but
the fruits of this aspect of general biology have had the unfortunate effect
of eclipsing work in other, more familiar, fields – a situation which we
believe to have resulted directly in the decline of funding for these areas
of biology.

The reason for this seems clear enough. The rise of molecular biology
has, without doubt, brought biology to the forefront of scientific research,
a position akin to that held by physics during the first half of this century.
It was inevitable that it should come to be seen as being the core of biology,
because it was clearly the discipline that advanced theories that could
be most widely applied. It became fashionable in biology to deride fields
that did not have as their aim the generation of fundamental theories along
the lines of theories in physics. In short, biologists became more interested
in the similarities between living things than in the differences between
them, despite the fact that many people who become biologists do so because
of their fascination with the diversity of life, not its homogeneity. It
could even be argued that this approach may reflect the increasingly homogeneous
nature of human culture today.

As we see it, there are three main reasons why special zoology must
survive. First, among the most pressing problems of the world today are
those concerned with the harm that people are inflicting on the environment.
Everyone is familiar with the facts of the destruction of the tropical rainforests:
last year saw the destruction of an area of rainforest the size of Belgium
in Brazil alone. We are all familiar with stories of endangered species
disappearing from vast parts of their range, or, indeed, from the face of
the Earth. The disappearance of many of these species is often a direct
consequence of our ignorance of their biology, in other words, their needs
for survival. It is only by studying elephants as elephants, or parrots
as parrots, or crocodiles as crocodiles, that we will be able to save these
animals from extinction.

General theories of molecular biology or ecology or ethology or physiology
will not answer such questions as: How many eggs per clutch does a blue-and-yellow
macaw lay? What is the geographical range of the crab-eating macaque? What
are the natural enemies of the South American paradoxical frog? Yet these
are often desperately important matters for conservation biologists. Such
questions are no less important than questions about the cells and molecules
of life; indeed, they are arguably more important for us to answer now,
because time is running out.

By concentrating research on molecular and cell biology (for medical
reasons) are we not acting in a rather short-sighted fashion? One might
question the value of medical research if the world as a whole is threatened.
Is it better to be 100-per-cent fit on a sinking ship, or to be somewhat
less fit on a ship that stays afloat? While we would not wish to argue against
medical research, we do feel that a balance must be struck. For this reason
alone funding for special zoology (and, indeed, special botany) should be
substantially increased.

The second point concerns the problem of animal identification. The
decline in numbers of special zoologists in recent years has meant that
fewer and fewer university departments contain staff capable of identifying
animals reliably, and the situation is getting worse. (Contrary to popular
belief, animal identification is not a routine matter. A specialist in a
particular group often has to work for many years before acquiring the necessary
expertise.) The practical need to identify pests and vectors of disease
in the medical, veterinary, agricultural and parasitological fields is vitally
important, but is becoming increasingly difficult to satisfy. Similarly,
biological surveys relating to the environment require a broad knowledge
of taxonomy. It is now well accepted among taxonomists that certain groups
of animals can no longer be reliably identified to species in Britain. The
best available estimates indicate that only about 10 per cent of the animal
species in the world have been described and named by taxonomists, rendering
the task of identification by non-specialists virtually impossible.

Thirdly, it must not be forgotten that it is the special zoologist who
supplies the general zoologist with problems to work on. Only by studying
the diversity of life will diverse problems come to light, and hence become
available for investigation.

The study of a particular animal species, or group of species, is often
derided in scientific circles these days. To focus attention on a group
of animals, rather than on an interesting and important problem, is seen
as shallow and unimaginative; a mere fact-collecting exercise – indeed,
stamp-collecting at its worst. It is very difficult to understand this attitude,
because equivalent approaches are regarded as being quite respectable in
the rest of science. A cell biologist studying a group of cell types with
a view to understanding their role in the body is seen as doing a worthwhile
job, but a systematist studying a group of animal species, with a view to
understanding their role in the ecosystem, is judged to be wasting his time.
Why? We have yet to hear a valid answer to this question.

In Britain, the science of zoology as originally defined and understood
(that is, the study of animals and their diversity) is disappearing. This,
despite the fact that it continues to be of interest to millions of people,
as the popularity of natural history programmes on television makes clear.

Few things can be as fascinating as the study of the diversity of life.
Yet the prevailing paradigm in modern science is that differences between
living things are superficial and uninteresting phenomena: only the deep,
underlying, equalising similarities are seen as being interesting and important.
We submit that this is a grey view of life – a view that will result in
the impoverishment, not only of the natural environment, but of human culture
and the human spirit.

The authors work in the Department of Zoology at the University of Cambridge.