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Biodiversity and Capitalism
Origins of agriculture
The development of diversity
Importance of diversity

Biodiversity and Capitalism
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For anyone who can pluck up the courage to read the newspapers - apart from just flicking through the crime headlines and sports pages - they are bound to feel rather uneasy when bombarded with all the daily reports of impending catastrophes of various types. Certainly the bourgeoisie would prefer it if the newspapers kept quiet about all the various problems that arise in the course of its frantic pursuit of profits, but, as everyone knows, so-called globalisation has made sure that anything that happens in one part of the world is of interest everywhere else: and that, combined with the fact that the sale of news is itself a business, means that plenty of news still gets out; even if usually it is a bit late in the day and the facts are inevitably distorted. Since it is in the bourgeoisie's interests to play everything down, we can safely assume that whatever bad news is reported about the environment, in reality, with few exceptions, it is a lot worse.

One of the most longstanding worries of our present epoch has been fear of a nuclear catastrophe, whether through war or an accident; another more recent concern is about global warming and the greenhouse effect radically transforming our planet. However, if you really turn your mind to it, it isn't difficult to find plenty of other things to worry about; such as cheap fuel coming to an end, the population explosion, lack of water, AIDs, cancer, chemical and bacteriological war, and so on and so forth.

Not many people know what biodiversity means exactly, and even fewer grasp its significance as a potential source of calamity for the human race: a calamity as serious as it is unfortunately inevitable unless the necessary steps are taken to avoid it. The loss of biodiversity in agriculture is a time bomb that is slowly ticking away towards ecological and alimentary disaster; and when it finally explodes it will probably be too late. We are on the brink of an abyss.

Maize rust disease was first recorded in the Philippines in 1961; soon afterwards it was reported in Mexico. The first signs that it had got into the United States appeared in 1968. In the Spring of 1970 it hit the maize crop in Florida (although this wasn't known until August... because of price rises on the Chicago stock exchange!). In the end, 15% of the harvest was lost, an enormous disaster.

The winter of 1972-72 in the Ukraine was particularly cold, and there wasn't enough snow. In the following Spring it didn't rain. More than 40 million hectares had been sown with a variety of high yield wheat which was susceptible to drought (Besostaja). It isn't known for certain the full extent of the drought but it was serious; so much so that in July the Russians purchased 27 million tons of wheat, a fact entirely without precedent. However, it wasn't so much the Russians who lost out as the poorer countries who depended on wheat imports: with cereal prices rising by 50% on the international markets, the cost of satisfying the hunger of Russian cattle meant starvation for millions of human beings.

In both cases it was genetic uniformity which was to blame. The most popular varieties, the proud product of modern genetic improvements, are potentially vulnerable to any number of environmental factors, and when they do become so affected, disaster inevitably follows because it is generally one, identical variety which is planted over vast areas.

In the period following the 2nd World War, research into the so-called High Yield Varieties (HYVs) led to the so-called 'Green Revolution'. This resulted in a steady impoverishment of the genetic pool needed to ensure healthy crops and the extinction of a larger number of old varieties.

In the early 70s, this problem prompted a reawakening of interest within the big seed companies of the North in the genetic resources of the South: the South, rich in climates and micro-climates, and never having been affected by the glaciations which in the North reduced the process of diversification, was able to develop an exceptional variety of forms of life. Thus a new phenomenon has developed, that of research into new genes and genotypes, an enormous business ripe for exploitation and one of the new frontiers of profit that has now acquired international political importance. But not even this new focus, rich in potential successes and discoveries though it may be, can hope to find a permanent solution to the problem.

To see how we arrived at this present state of affairs, it might help to get our bearings if we retrace our steps back to when biodiversity existed in its natural state, that is, before human beings got their hands on it.

Origins of agriculture
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Humanity has always lived from hunting an gathering, or rather, almost always. Only in the last few thousand years has humanity gradually passed over to agriculture, and even then, not entirely. Only a few centuries ago a large part of the world's population lived entirely from hunting and gathering. Even today, in a few inaccessible places, difficult to reach by jeep or helicopter, there still exist a few embattled ethnic groups immune to TV, Coca-Cola and double-entry book-keeping, in short: immune to civilisation.

What kind of life did these hunter-gatherers lead? Thanks to archaeology and the study of still undisturbed descendants of the hunter-gatherers in the last century, all are by now agreed that life wasn't all that bad - they had culture (rituals attended the burial of the dead, they had a perfect knowledge of their immediate environment, they had a fund of techniques developed around the processing of food, and hunting, they had means of communicating this complex knowledge) and they had developed a social life.

Food was abundant and there was enough wild game and plant material to provide for the small population that dwelt in its midst (even the bushmen of south-West Africa spend on average only 9-12 hours per head, per week, providing themselves with food; and the same can be said for the Amazon Indians: the inventors of the hammock). Moreover, not much time needed to be spent on other essential tasks either.

The diet was extremely healthy and varied, and was derived from an extremely wide choice of plant species (3000-5000 in North America alone).

Famine didn't occur (unless caused by the intervention of other human groups). Although this sounds incredible it was the case. The eco-systems which sustained them were stable, and the sources of food so numerous that it wasn't possible to eradicate them all at once. Famines are an invention of agricultural societies, as indeed are most 'natural disasters'.

There was therefore little incentive to change this style of life, and this can be seen in the ethnic groups that have recently entered into contact with civilisation.

Why and how then did agriculture arise? The old hypothesis that one day, 10-12,000 years ago, somebody suddenly decided they were fed up with their varied but casual diet and invented agriculture is now discredited because agriculture seems to have arisen almost contemporaneously in widely separated parts of the world. What is far more likely is that a very gradual transition took place (with pauses, steps backward, and blind alleys) from hunting and gathering to stock-farming/cultivation.

What could have caused this transition? One might think it was something to do with hunger; since agriculture is much more productive per area unit, maybe it forced our ancestors to cultivate the land to feed an increasing population? This explanation doesn't hold up, however, if one takes into account that a time of hunger isn't conducive to initiating a lengthy process like cultivation, much less inventing it, especially so if it isn't yet known that agriculture would be any more productive. Rather the tendency would be to eat all supplies, stock and seeds included.

Probably the first plants to be cultivated were ones which were especially precious or rare (medicinal, ritual, dyes, poisons) which were difficult to find, and necessary in small quantities. Later on, particular circumstances (like a reduction in game as a result of climatic change or over-population) might have caused an increased dependence on any plants cultivated around the village. And it was women who were probably the first cultivators. Eventually, a time arrived when the tribe instead of migrating in search of new, richer territories (maybe none existed in the vicinity, or they were surrounded by hostile tribes) stayed where it was and became more dependant on agriculture.

As sedentariness increased, so also did the population. Men no longer set off for long hunting expeditions, and more people were able to work the land and exploit its resources; men could also dedicate their energies to agriculture. Gradually, as well as bringing about an increase in the amount of land utilised, there was a corresponding improvement in technology. This in its turn meant a further increase in production and further demographic growth; a phenomenon that one can still see today.

The plants that exist today are not the same as the ones cultivated in those faraway times, and in fact they hardly resemble them at all. Today's plants are domesticated, that is: transformed to suit man's requirements.

Domestication principally consisted in making choices about which seeds would be sown, and therefore which plants were worth perpetuating. Thus it is that so-called 'selection' takes place: a selection which has now become directed rather than natural. Domestication is therefore a form of evolution directed by man. What are the characteristics which governed mankind's choice of useful species? The first species to be domesticated possessed traits which were highly important for the new alimentary technology: the seeds were easily preserved and stored; there was a high level of starch in the cereal seeds and a high protein content in the seeds of pulses. There were also other characteristics:
non-dispersing seeds: if the seeds are easily detachable from the spikelet (ear), it means the amount of grain that can be harvested by man is reduced, even if this quality is advantageous to the plant in its wild state.
contemporaneity of maturation: another feature which is negative for the species in its wild state but advantageous in terms of agricultural yield.
contemporaneity of germination: the same as for the previous point.
Other important factors include indehiscent pods (beans etc), that is, pods which don't open naturally (increasing the yield), as well as loss of defensive properties (spines, toxicity).

The more plants became modified, the more people devoted themselves to an increasingly productive agriculture. In consequence, they increasingly began to lose their hunting and gathering habits (never entirely abandoned however). As a result of this change, so the ecosystem within which these peoples worked changed.

Thus it came about that less and less plants came to make up man's diet because the ones which had been improved were more productive, and therefore less wild plants were gathered. Today, in place of the many thousands of species which made up the diet of the gatherers, only around 130 species are cultivated, and out of these, 85% of food is derived from only 8 species - and out of these, rice, wheat and maize provide us with 50% of our food.

It must be emphasised, let's be clear about it, that this domestication of around 200-250 species over the last 10,000 years was an enormously important conquest. Nowadays though we are losing a major part of the results of this achievement, whilst wild foods are now virtually non-existent in our diet.

The development of diversity
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Thus, with domestication, Man drove forward the evolution of cultivated plants; a difficult to define process with many twists and turns. There is a well-known story about a famous geneticist who asked an African farmer why he selected crooked sorghum plants for the following season's planting; the answer came that if all the plants had been crooked it would have been easier to hang them on the roof of his hut. Aims have therefore been many and various, with some more important than others depending on the epoch. Plenty of other examples of this domestication exist. The coloured maizes of South America were important because the colours indicated other characteristics then considered useful; the cucurbits also served as musical instruments, as containers for liquids, feather holders, as well as for food. Sorghum in Africa was used to make brooms, to make molasses, for chewing, for making bread and beer, for construction, as a colorant etc, etc. In Peru there were different coloured varieties of cotton so it wasn't necessary to dye it.

With the development of each food crop there came a parallel reduction in the impulse to domesticate other species. Nature's diversity wasn't lost, but it wasn't made use of any more, and in time the knowledge of how to use it was forgotten. There was however a huge increase of diversity within the domesticated species; two villages separated by a mountain could develop two distinct types of bean, either because the habitats were different, or because tastes in food differed. Up to not so long ago, certain vegetables were produced only in certain places. Diversity was favoured by environments which were morphologically irregular, like hills and mountains.

Over the course of thousands of years of domestication, most crops therefore had to adapt themselves to the most varied conditions producing very varied genotypes. This is why many species are found in the most diverse situations. The apricot, for example, is found throughout the hot environment of the Mediterranean, but it is also to be found on the slopes of the Himalayas. Sorghum can be found typically in both the humid tropics and semi-arid zones. Rice is found in India at sea-level and up to 2000 metres above. The potato though possesses the greatest adaptability and can be found from below sea-level up to 3000 metres above, ranging from the Arctic circle to Africa.

These genotypes are all varieties, or cultivars, of the same species, and they differ the one from the other usually only in regard to a very limited number of characteristics. In general, there are two main factors at work behind this diversification: mutation (the casual appearance of new characteristics in an individual, followed by selection by man) and introgression (the appearance of new combinations of already existing genes, either as casuals or guided by man through hybridisation).

The 'oddities' which interested Man were plants with new and useful features with regard to resistance to disease and insect pests, adaptation to extreme environments, quality and quantity of production, etc.

In order to gain genetic improvements through introgression, it is necessary to have present in a population of plants a wide genetic variability in order to obtain a large number of genetic variations from which to choose. For any given species this variability is highest in surroundings where it has existed for a long time, because it has had greater possibilities to produce new forms. These surroundings are obviously those in which the species originated.

At this point we have to talk of the biologist and geneticist Nikolai Ivanovich Vavilov, a genius little understood outside geneticist circles, who travelled the world from 1916 to 1940, observing and collecting plant specimens. Respected during his lifetime, and still respected today, it took the stupidity of Stalinism to put him in a prison camp, where he died of hunger in 1943.

His most important discovery was that genetic variation, the diversity created by millions of years of natural evolution and thousands of years of agriculture, wasn't equally distributed throughout the world. Vavilov drew up a map of the distribution of the diversity of each of the cultivated species which he had studied. He also hypothesised that the level of diversity was indicative of how long a species had been cultivated in a particular area: the longer the time there, the higher the level of diversity one could expect to encounter; the greater the number of uses a plant had, the more varieties and forms there would be. For example, there are different types of maize for pop-corn, for ceremonial and medicinal uses, and for roasting. The same goes for a species' defences against insects, pathogens etc. Vavilov thought that by identifying the geographical centre of genetic diversity of a cultivated species, it would also be possible to identify the area where it originated - which in its turn, had to be in the zone where cultivation had had the time and opportunity to develop a large number of variants. Vavilov located eight such geographical centres, and in general, these were mountainous zones, or at any rate, areas containing a variety of habitats. Mountainous regions provided the ideal conditions for variation, in that there existed topographical variety with a range of climates and soil types. Mountains also formed excellent natural barriers against external incursions, and blocked the exchange of genes even at a local level.

Since the centres of origin weren't just centres of one, but of numerous, species, Vavilov theorized that all cultivated species had originated in the eight centres of diversity he had identified.

Nowadays the centres of diversity are not identified with the centres of origin. For a centre of origin to be considered as such, the wild progenitors of the cultivated species must also be present, as well as a certain level of variation. According to this interpretation, Harlan identified only three centres of origin, which were also recognised as centres of early agriculture. The other five centres which Vavilov had identified became seen as secondary centres of diversity to which agriculture had spread later on, and where the process of domestication continued. With changes of habitat, the cultivated species had to undergo processes of adaptation still more drastic than before. Thus has diversity travelled on the great journey of agriculture which went on to conquer the world.

Importance of diversity
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In ancient times, when agriculture was still proving its worth and expanding out of its original centres, an equilibrium came to be established between plants, insect pests and diseases; this was possible because the rate at which the species, and the eco-system of which they were a part, changed was extremely slow, and there was therefore plenty of time for a co-evolution to take place.

The primitive varieties were characterised by a marked genetic variability insects and diseases did indeed cause damage, but the damage was restricted by the diversity of genotypes, many of which possessed effective defences. Also fields were dispersed and often separated by forests, and therefore it was difficult for infestation to spread: cultivations might be damaged, but not devastated.

This situation would change with the spread of agriculture, and later on with the concentration of a few genotypes (sometimes only one) over vast areas.

A typical case is of what happened to the potato in Europe: although it was widespread in South America, it was only introduced to England and Spain in the 16th century. Slowly it spread, but still on the basis of those two initial introductions, and therefore on a genetically very restricted foundation. In Ireland it became the principal food. The arrival of Phytophtora infesters (potato blight) meant the destruction of the entire crop, and a famine which resulted in millions of dead and millions more emigrating to America. Genes of resistance existed but they were to be found in the Andes, and if not for them the potato would be unknown to us today.

Despite this, and many other similar lessons, the development of modern agriculture has followed other paths. The presence of different traits in the traditional varieties has helped to create new varieties adapted to particular situations, but obviously not to all situations. With the development of genetics which followed Mendel's discoveries, and with the development of agricultural technology, it became possible to create ever more productive varieties adopting the technique of the 'pure line' in seeding species, and 'clones' in trees. In both cases, crops consisted of genetically identical individuals. Thus the fields would increasingly present a picture of genetic homogeneity (in place of what has been defined as «harmonious disorder»), planted with varieties which responded positively to input of fertilizers, cultivation and irrigation, and with biotic enemies held at bay with low cost treatments produced by the new chemical industries.

But all this was not enough to prevent further disasters: in 1870 the coffee plantations in Sri Lanka, India and East Africa were completely devastated by rust disease (turning England into a nation of tea drinkers). In the decades which followed further disastrous pathological events hit cotton, wheat (USA), rice (India), oats (USA), maize (USA) and wheat (USSR).

Every time, what was needed was resistance, and every time resistant varieties had to be tracked down in the centres of diversity; amongst the traditional varieties which had survived, or amongst the wild ancestors of the stricken crops. This resistance will always be needed to deal with the problem, because over time insects and diseases mutate and evolve resistances to pesticides.

In this century alone, examples of crops saved by traits derived from wild varieties are too numerous to mention. The diversity of the wild varieties has rendered them capable of surviving without assistance from man. If their resistance hadn't allowed them to survive, they would have been extinct a long time ago. Therefore, as a source of resistance, the wild varieties represent an invaluable resource. In the words of Harlan: «the wild relatives stand between mankind and starvation».

And that's the issue: the wild relatives of our crop plants, as well as the old varieties, will always be needed. Therefore, the habitats in which they still continue to grow and evolve are also needed. In thislies the perennial importance of the diversity of plants: agriculture won't survive without diversity.

Source: «Communist Left», n. 14, 2000

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