Keywords: culture; biodiversity; ecology; sustainability
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The Realm Of The Living Culture involves order One might not guess it from the hurly-burly of daily personal life or current news, but the quest for order is a profound necessity. All animals become neurotic in the midst of confusion, while the 'superstitions' of primitive people serve to stabilize life by giving some kind of explanation of the otherwise unexplainable. Science, with all of its limitations, is the fruit of this quest for order in nature, providing a discipline of method and expression universal for cultural development of humankind. Most of us take short cuts to provide us with order, using stereotypes for Chinamen, roses, trees, horses or snakes. Probably because dogs are so intimately associated with us, we are less inclined to ignore differences between the breeds. Yet even here the fancier is aware of technical differences of which the average individual knows nothing. Biodiversity is a culture of order When it comes to the hundreds of thousands of kinds of plants and animals in nature, there are, and perhaps have always been, some individuals keenly sensitive to the resemblances and differences among them. But it was not until the early eighteenth century that a generally effective method of tackling this problem of classification was inaugurated. Whether one is sorting mail or potatoes, he must have a basis for the operation and pigeonholes or piles for each sort. If there are many kinds, labels are essential. In the field of natural history it was the lively, prodigious Swede, Carl von Linne or Linnaeus, who set up a practical working system which is used as the international standard.. His interest took in minerals as well as living organisms, and his was the famous aphorism 'Lapides crescunt, plantes crescunt et vivunt, animales crescunt, vivunt et sentiunt'. (Rocks grow, plants grow and live, animals grow, live and are conscious.) With a keen eye for essential characters, he combined practical sense in the matter of labels and gave us-or rather made official -a standard two-name system that we still use. The first denotes the general kind, as cat or maple, the second the specific kind, as tiger cat or red maple. And fortunately he had at his disposal the well-tempered and scholarly language of Latin, dead enough to be stable, alive enough to be civilized and known. Combined with adequate description and backed up by preserved specimens, this made possible definite international understanding. Order is the first step to usefulness On July 2 1741 Linnaeus was in the village of Gothum. His diary entry for that day was:-
In the Linnean system of classification, this small facet of applied botanical biodiversity involves distinguishing the characters of Hypericum perforatum from Anthemis tinctoria in order to disemminate this locally invented technology. As a basis for classification, Linnaeus employed the species-a form so distinctive as to be readily recognized as unique. This involves at once an element of judgment or intuition, unhappily more troublesome than the precise measurements that serve the physical scientists so well. And though we know today that the concept of species involves serious complications, we still find it essential. Faced with the fact that no two individuals are ever precisely alike and the further fact that external resemblance may hide important differences of behaviour and biochemistry, we have to get on with the business of sorting as best we can. Scientists still call the tiger Felts tigris L. and the red maple Acer rubrum L., the L. being an acknowledgment that Linnaeus himself had named them so. Useful as this device has been, the task of cataloguing the hundreds of thousands of species in the living world is far from complete, to say nothing of the differences of judgment among authorities as to the proper identity and naming of those already listed. Moreover, the species and genera must be grouped into higher echelons. The philosophy of these higher groupings was at least clarified by the doctrine of evolution which assumes, with good reason, that any classification should be based upon degrees of inherited kinship. This has to be inferred from as many kinds of evidence as possible. Not only resemblance and differences in appearance, but geographical distribution must be taken into account. More recently biochemistry and refined microscopic methods have been employed, as well as ecological experiment. For example, the proteins of any species are characteristic and the nearer the relationship of two groups, the more alike their protein component may be. A hay fever victim, sensitized to one member of the composite (ragweed and sunflower) family is generally sensitive to others, but perhaps immune to the proteins of the grass family. In fact, the behaviour of blood serum from a sensitized animal has been used to determine degrees of relationship among species to be tested. This protein incompatibility has wide applications, not only in classification, but in disease resistance and sexual reproduction. The specific properties of proteins are important ecological factors as between organisms. Again, such microscopic characters as the form of pollen grains and the detailed structure of stems may reveal useful information as to affinities. And within cells the number, form and arrangement of chromosomes, the bodies that contain the genes in which are encoded the patterns of inheritance. The comparison of DNA codes is now indispensable in untangling relationships, particularly within genera. Variety and distribution Life
in all its physical and chemical complexity exists in a multitude of
forms, or species. Current estimates show that about 300,000 species
of green plants and fungi and about 1,300,000 species of animals have
been recognized by biologists. These figures do not include the bacteria
and yeasts, of which there are thousands of types, and undoubtedly there
are many thousands of species of other groups of organisms remaining
to be discovered. None of these forms of life is distributed haphazardly
over the surface of the world. Each species occupies only a limited
area of part of the global environment, although the size of the area
occupied varies greatly from species to species. There are very rare
species that are found in only one or two places, and others that are
very common and found almost everywhere. But even the most common species—such
as our own Homo sapiens—do not live everywhere; very few people
live in the polar regions or in desert areas. In fact, unevenness of
spatial distribution is as basic a characteristic of living organisms
as locomotion or respiration. Ecologists
seek to understand how each species has evolved so that its life processes
of physiology, growth, and behaviour function efficiently only within
a limited range of environmental conditions, and with only certain types
of food resources. This is probably a result of the pressures of competition
between species for the limited space and food resources available in
their environments. Only by ever-increasing specialization in the space
it occupies and the food it uses can a species gain some competitive
advantage over others. This process of specialization—adaptation
to particular factors or combinations of factors in the environment—is
a continuous one, and has occurred by the evolutionary process of natural
selection. It can be assumed that ,because the physical conditions of
the organism's environment— temperature, light, wetness or dryness,
and so on—and the food resources it contains are far from evenly
distributed, the distribution of organisms must also be uneven. Each
species therefore has a pattern of distribution related to that of the
physical conditions and food resources to which it is adapted. The study
of the patterns of distribution of organisms in space and time is called
biogeography. Classification, however, is to the ecologist a tool, rather than a goal. The objective is to understand the play of life, and to do so the actors must be characterised.. More important, it must be know how each fits into the plot and the part it performs. So, quite appropriately, the ecologist borrows from common speech two useful words- niche and role. Niche means opportunity, role means function. NicheLice find their niche in the feathers of birds and hair of mammals, weeds find theirs in soil that has been disturbed, North American squirrels have their niche in the oak and hickory forest. Life began in the seas, or at any rate first became abundant there. Since food had to be manufactured with the aid of sunlight, available niches-or one great niche if you prefer-were at first confined to the upper layers that light could penetrate. Light decreases rapidly with depth. Depending on the clearness of the water, food-making plants must operate in a zone not deeper than between 30 and 300 feet. Once these pastures of the sea were established, they afforded in themselves a niche suitable for the evolution of animal life, and the wastes of both plants and animals afforded a further niche for the organisms of decay. As animal life increased in individual size, complexity and power, it found niches open at greater depths. Here it could feed upon organic material sifting down from the lighted zone- a niche for the less active-or make forays upward to dine upon the small plants and animals in the lighted zone-a niche for the strong and vigorous. In other words, the increasing variety and abundance of life itself vastly multiplied the number of niches. And the process of evolution, made possible by the unceasing tendency of organisms to vary and increase in numbers, provided plenty of pressure upon any niche that might be opened up. In the long course of time, the seas thus became populated and their life patterned. But not uniformly. Differences in temperature, day length and chemistry, demanded a range of qualifications among their prospective tenants. Where upwelling currents brought to the surface an abundance of nutrient minerals from below, life itself became more abundant, as the great fishing grounds of the modern world demonstrate. Ocean voyagers crossing the Gulf Stream note the presence of flying fish and other warmth-loving organisms absent from the colder waters through which this noble current makes its way to the northeast. On land the same great principle has operated. The ceaseless experimentation and exploration of living forms has been an unending course of filling available niches as they opened up and by that very fact creating new ones for others to occupy. The result is a web of makers and users, eaters and eaten, collaborators and competitors. Tracing the skein of these intricate relationships is the profession of the ecologist, which deals with problems whose complexity and delicacy can challenge the utmost resources of modern science. Many of them must be turned over to the geneticist, biochemist or biophysicist, just as at the start of a studies, the aid of namers and classifiers must be sought. But the division of labours is by no means hard and fast. Many ecologists are versatile, and many specialists are able to take their own cues from natural situations. Before problems arising in the field are ready for transfer to the experimental laboratory, however, there is still work to be done. Once the organisms in a community and their visible means of support-that is, their respective niches-are known, the stability of the system has to be accounted for. Even where succession is taking place and where the condition of a steady state has not been reached, the approach towards it is ordinarily a matter of development rather than revolution. It is reasonable to suppose then that the members of the community, and not solely some outside influence, contribute towards regulating conditions. Certainly each organism has some effect on the situation. Not only does it have a footing, but it plays a part. That part we call its role. Common sense, as well as a good deal of evidence, leads us to believe that the interaction of these many roles tends to balance the system or, at worst, not to disrupt it. Any component that is completely disruptive would, in the long course of time, tend to become self-destroying. The more we know about great natural areas of plants and animals, the more we marvel at their resilience, their capacity to heal themselves from disasters of nature such as flood, fire, hurricane and drought. Even when industrialism tips the scales against them, they struggle to recover. Any abandoned field or road shows that clearly enough. We come, then, to think of the plants and animals of any living community not as mere occupants but as members of the household, and are at once reminded of the difference between a boardinghouse and a home. A house shakes down into a home by virtue of being lived in and takes on character thereby. And the word 'household' takes us back to the original meaning of ecology - from oikos, household and logos, the wisdom or system Role Survival demands vigour and fitness. The very balance of the system demands that each species come to terms with limitations. The immense reproductive capacity means high mortality to hold numbers in check, as we shall see. Yet this very elimination tends to favour the quality of those that survive. And the roles of these survivors are varied beyond belief. Take the North American squirrel as an example. The hollows of dead trees- killed by fungous disease and excavated by woodpeckers-afford him a home. Acorns and other nuts he stores there against winter. Others he buries in the ground, to be kept moist and dug up on bright warm days in winter and early spring. Some of these he may not use, whether from death, surplus elsewhere or sheer absent-mindedness. Thus conveniently planted, they often survive to germinate and begin life as seedlings. Emerging from his winter inactivity (low temperatures render him sluggish or put him to sleep) he scampers through the branches of the forest, cutting off and dropping twigs that are in his way and eating succulent buds, rich in reserve food. In this way he probably does a great deal to eliminate surplus stems which, if allowed to develop, would certainly compete with each other for light in the interior of the tree crown. Just how valuable this pruning activity is to the balance of the woodland itself, is not known. But there is no doubt that his habit of burying nuts is as valuable to oak and hickory as the food they furnish is to the squirrel that buries them. This by no means completely describes his role. He dodges snakes, hawks, owls and foxes, but if caught, he nourishes them, and they in turn prevent his numbers from becoming excessive. He defends his nesting and feeding territory, keeping others of his kind distributed at distances favourable to all concerned. His droppings enrich the forest floor, while his body, inside and out, may nourish a variety of parasites. To say that squirrels are lousy is simple truth and no disparagement. Values and choices From the lofty trees which dominate the forest, giving it its characteristic structure, to the smallest invertebrates, bacteria and molds that rework the wastes of the system, each organism survives thanks to the existence of the niche into which it fits. Each in turn plays some role that, by and large, tends to keep the system in working order. There is, in this system, much still to learn and perhaps more for us to understand. Not only is it difficult to reduce what we see to the nice exactness of mathematics, which is the aim of science, or at least its ideal, but we are limited by our human habits of thought. To us, for example, disease and death are wholly evil. Even if we concede the necessity of death that others may follow us and enjoy, as we have, the privilege of being alive, it is hard to justify the existence of organisms that cause disease and suffering. Being eaters ourselves, we can perhaps become reconciled to the endless cycle of eater and eaten, but the idea of ourselves and fellow creatures having to cope with invisible bacteria and viruses seems strangely wrong. Leaving aside our frequent prejudice against other humans, it is even difficult for us to concede any ethical obligation to preserve other forms of life that do not immediately serve our purposes. Some are inconveniences, others nuisances or worse- from our viewpoint. Ever since the beginnings of agriculture, trees have been our rivals for space. Only the fact that they furnish usable material and protection from the sun has been convincing enough to preserve as much of forest as we have. Their contribution to the beauty of the landscape has been regarded as a luxury which, like costly tapestry, is to be maintained at the expense of those who can afford if. From the air, one has only to look down at the barren, bulldozed housing 'developments' that dot our landscape from coast to coast, for all the world like measles from that vantage, to realize what price beauty. Beyond this, do we question the morality of ruthlessly destroying a beautifully organized pattern of life that was operating long before our advent and indeed helped make the earth habitable for us? Only as we learn to see and appreciate for ourselves these systems of living communities will we begin to respect and cherish them and share the landscape with them in a generous fashion. Nor dare we forget that, if we ourselves survive into the distant future, we, like the plants and animals which preceded us, will eventually have to come to terms with environment. We may do so by clearing away everything except concrete and asphalt, living in masonry cells and finding nourishment through elaborate systems of glass, plastic and metal, housing intricate chemical operations. But whatever system we choose to survive by, it must be based on the essential dynamics of natural communities as systems, where a species and as individuals must find our niche and perform our role. Never before in earth history has a single species become the worldwide dominant that man is today. Without changing our bodily form, we have been able, by fashioning the materials about him into tools, shelter and clothing, and by using the energy stored in wood, coal and oil by plant life, to transcend the barriers of climate. Drawing still further upon fossil energy stored overf millions of past years and devising machines to be run by it, we have displaced the very pattern of use and reuse which had provided us with the means of survival. For food and fibre we have become dependent upon domesticated plants, many of which would not survive without our nurture of them. Systems thinking In producing crops we rarely follow the balanced model that exists in nature. Instead, we take the factory and the bacteriological laboratory as our model, sterilizing the soil of plant and animal life and substituting pure cultures of what we want, and drawing upon fossilized sunlight to help produce it. The wastes of our vast numbers are only in small measure converted for reuse. Instead they are discharged, often in harmful form, to river and air. Having freed ourselves, for the time being, from those restraints that operate in nature upon other organisms, our numbers continue to increase geometrically. These things we have done by making use of systematic knowledge of biodiversity. But in employing that knowledge for immediate ends, we have become so absorbed in the technicalities of production to the point of forgetting that the highest function of science is to give us an understanding of consequences. It
is not enough to understand a landscape's forms and cover. The environment
must be seen as a manifestation of the flows of materials and energy.
The laws of the conservation of energy apply to a culture as truly as
to the design of its engines, the general transport and use of itspower.
The health of a cultural ecosystem, that is, its capacity to sustain
human life, is measured by the efficiency with which we think of cultures
as managed systems where survival is a matter of controlling the fossilised
and current solar inputs of energy between reception and its inevitable
dissipation. A truly healthy ecosystem is the rule rather than the exception
in nature. Like a well-run industrial plant, it tends towards a combination
of maximum production and optimum maintenance. It represents what the
physicist calls an open steady state, a condition of equilibrium that
continues to receive energy, do work and at the same time keep itself
in working condition. In such an environment we find the proper model
to sustain our industrial cultures, and apply conservation management
to their green spaces. Prescientific
people of simple ways have been known to follow this model intuitively,
often safeguarding the stability of their hunting grounds, fields and
water sources by religious belief and taboo. In this spiritual sense
there can be no argument that such greenery is sacred. So it is that
hill people protect their terraced fields with wedges of forest and
believe that the destruction of those forests will call down the wrath
of their ancestors. Scientific cultures have often ignored this model
of nature and paid the penalty of a disrupted and depleted environment. So
long as we strive for ever expanding consumption of goods and services
in a finite environment, and remain a species whose capacity for increase
follows the law of compound interest, our wealth which inheres in the
environment will eventually give out.. To assume that, finite as it
is, it can continue to endure ignorant and unlimited pressure, whether
from numbers or abuse, is to ignore simple mathematical truth. And respect
for truth comes close to being the basis of all morality. Adapted
from the words of Paul B Sears; 'The Biology of the Living Landscape';
George Allen & Unwin (1962)
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