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  • 1. Evolution, genetics and society By Ian Sanders "Organic Life beneath the shoreless waves Was born and nurs'd in Ocean's pearly caves; First forms minute, unseen by spheric glass, Move on the mud, or pierce the watery mass; These, as successive generations bloom, New powers acquire, and larger limbs assume; Whence countless groups of vegetation spring, And breathing realms of fin, and feet, and wing.” (Erasmus Darwin, The Temple of Nature) The problems posed by genetic science are philosophical as well as ethical and spiritual. The aim of this article is to explain the philosophy underlying current genetic research, and correct misconceptions held by public, media, industry and scientists. In particular I wish to consider the role of genetics in plant and animal breeding, and in human health. The origins of evolutionary theory To explore how this philosophy arose; it is necessary to go back to the beginnings of evolutionary theory. I refer throughout to evolutionary theory, rather than Darwinism, because I believe that the Theory of Evolution owes as much to Lamarck, Wallace, Lyell, Blyth (who began writing a paper entitled The Origination of Species) and Erasmus Darwin (grandfather of Charles), as it does to Charles Darwin. Similar ideas had been circulating for decades at least before the publication of The Origin of The Species. At best, Charles Darwin could be credited with discovering the mechanism of evolution (natural selection of random mutations), but even this is debatable1. Evolutionary theory arose out of a range of scientific and social theories, which were current in Victorian England. This paradigm continues to influence politicians, the media, and the biotechnology industry, even though many (possibly most) evolutionary biologists rejected it long ago. Progress and evolution One implicit assumption that was tagged on to evolutionary theory was the idea of progress. The Victorians were great believers in progress. Britain had been the first country to industrialise, and by the time of Darwin, was ruling much of the world. It was easy for certain Britons to believe that white Europeans (and especially the British) had proved their superiority over other races. The fact that the average working class Briton had a lower standard of living than the average Australian aborigine was conveniently ignored, as was the tendency of empires to rise and fall. The industrial revolution had actually caused a decline in average living standards, which was not totally reversed until the twentieth century. The medical profession had grown into a wealthy and respected industry during this time, but of all their remedies, only smallpox vaccination significantly increased life expectancy. Improved sanitation increased life expectancy in the latter half of the 19th century3, but this should not be regarded as progress, rather as the solution to a man-made problem: It was industrialisation and the consequent growth of overcrowded cities that had created the outbreaks of cholera, dysentery etc. The idea of social progress combined with the concept of “The great order of being” as proposed by Pope, in which all species have a place in a hierarchy of life, and both ideas coloured evolutionary theory. Evolution was seen as “progress up” the hierarchy of life. The ape King Louis expresses this idea in The Jungle Book: “I’ve reached the top and had to stop, and that’s what’s
  • 2. 2 botherin’ me”. The misconception is a subtle one: Evolutionary theory does not state that humans are “descended from apes”, rather that humans and apes share a common ancestor. Modern day apes are the cousins of humans, and therefore have been evolving on the earth for precisely as long as humans, whales, elephants, sharks, fungi, plants and bacteria. DNA analysis has raised the possibility that modern day chimpanzees could be descended from early humans. This does not mean that they “regressed”. The majority of organisms on earth are simple: bacteria, algae, moulds, protozoans etc. Every species of vertebrate (mammals, birds, reptiles, amphibians and fish) has at least one unique parasite. Parasites and hosts follow each others evolution. The human tapeworm has no gut, no internal organs, just a long body, adapted to living in the human gut, soaking up pre-digested food. It has been evolving as long as we have, yet remained simple. Sharks have changed little since the time of the dinosaurs, because they have not needed to. Evolution has no direction. Species can become more or less complex, more intelligent or less intelligent, faster or slower, stronger or weaker depending on the environment in which they are living at a particular time. Organisms may remain apparently unchanged for millions of years, or they may evolve in ways that are not immediately obvious to us: subtle changes in their biochemistry for instance. To paraphrase Stephen Jay Gould, life is not a ladder, it is a tree. Looked at in this light, there is no hierarchy of nature, and no such thing as a “primitive” or “advanced” organism. This obviously creates ethical problems: If humans are not “more advanced” than other organisms, how can killing animals for meat, or using animals in medical research be justified? Worse still, if vertebrates are not “more advanced” than insects, bacteria or plants, must we all adopt the extremes of the Jains, who go naked to avoid killing fleas on their skin and don’t even kill whole plants for food? The Jains are in any case attempting the impossible. Their immune systems kill microbes and parasites every day. Personally, I feel that rather than trying to cut ourselves off from nature for “moral reasons”; we should be more aware of our position within the food chain and try not to upset the rest of the chain. The concept of progress is misleading for another reason: Technological change (which may or may not be “progress”) is happening far more rapidly than human evolution could possibly occur. Evolution by natural selection requires generations for the smallest change to occur. Only a handful of evolutionary changes can be shown to have occurred since the dawn of civilisation, e.g. the ability of some races to tolerate raw milk and alcohol. In contrast, major social and technological changes can happen within a few years. Richard Dawkins has invented the concept of “memes”: units of social inheritance such as ideas etc. that are reproduced and spread by word of mouth, books, and telecommunications4. Memes, he suggests evolve like genes, only much faster. Ironically, by this logic, the meme concept is itself a meme, albeit a rather unsuccessful one! The meme is an elegant attempt to link evolution and social change, but there are still clear differences between the two: evolution creates new forms from old ones. The human hand has evolved from the same limb that gave rise to the bat’s wing and the dolphin’s flipper. New aircraft are not built from pieces of old aircraft, and the designs are often radically different from anything that has come before. Stephen Jay Gould, suggested that the best analogy for evolution in human technology is the widespread third-world practice of making sandals out of old car tyres! Another example is the canoe, the basic design of which is found all over the world, whether made from a hollow log, from birch bark, or from animal hide on a wooden frame. This could be seen as analogous to convergent evolution, the process by which unrelated species in similar environmental conditions evolve to closely resemble one another, e.g. the wolf and the thylacine, or Tasmanian wolf. Car-tyre sandals and birch bark canoes are rarely cited as examples of human progress!5 6 Charles Darwin was heavily influenced by Lyell’s idea of gradual change over millions of years (gradualism), and he rejected notions that evolution might occur in sudden leaps (punctuated equilibrium). Prior to Lyell geologists had believed that fossils of extinct animals were creatures which had died in the great flood, or in a series of catastrophic floods, of which Noah’s flood was only the most recent (a belief known as catastrophism). Many scientists and clergy doubted the literal truth of Genesis long before Darwin. Ironically in recent years, the idea of punctuated
  • 3. 3 equilibrium in evolution has gained a lot of support. Recent geological research has shown that numerous times, life on earth has been nearly eradicated by catastrophic events, such as meteorite impacts. Gould suggests that there is a considerable element of chance in evolution: When a large meteorite hits earth, whole classes of organisms can be wiped out, leaving a few survivors to diversify and fill the available niches. If events had been even slightly different, the dominant animal life on earth might have resembled giant woodlice! Ironically the catastrophists are being vindicated. Darwin also coined the term “survival of the fittest” which has proved very misleading. By “fittest”, Darwin meant “best suited to survive”. Survival of the fittest means therefore “survival of the survivors”, a tautology. Physical fitness is a result of lifestyle rather than of genes, and is therefore not inherited. If evolution is seen as a process of diversification, rather than a “race to the top” the idea of constant, desperate life and death struggle becomes less valid. It is the idea of evolution by blind chance that appears to conflict most strongly with Christian teaching, as it seems to rule out the need for a creator. However, creation can be viewed as a continuous process, from the creation of the universe until now. Those on the extremes of the debate (insisting either that the world was created in 6 days or that everything in the universe is the outcome of blind chance), seem to have a very narrow concept of what “creation” and “God” are. One side insists that life is the inevitable result of a particular set of conditions, and natural laws, without questioning how those conditions and laws came to be the way they are.The other side clings rigidly to a set of metaphors from another era: the thunder god, who creates man from clay. Darwinism and Genetics Modern genetics is said to begin with the research by the Austrian monk Gregor Mendel into breeding of sweet peas, which concluded that there were “units of inheritance” for traits like plant height and flower colour. Mendel’s “units of inheritance” are what we would call genes. Darwin had read Mendel’s work, but failed to see its significance. Mendel’s work was rediscovered in the early twentieth century, but since then, even with the discovery of DNA structure in 1953, genetics has not made any great improvements to our lives. Mendelian genetics in medicine Mendelian genetics has made it possible to examine family trees, identify certain hereditary diseases and then advise couples whether or not to have children if there is a risk of those children inheriting the disease. This only works if the disease has been identified as hereditary, and the couple is aware of the risks. This approach is unlikely to be useful in preventing most hereditary diseases, simply because there are so many hereditary diseases in the world. The average person is a carrier for about 6 (usually rare) fatal recessive genetic diseases. These diseases will never be expressed unless two people carrying the same disease have children together. Even if everybody kept detailed family trees, and consulted a geneticist before having children, it is unlikely that this would prevent many children from being born disabled, as so many diseases would remain undetected. Adultery would of course create further complications. The best advice any geneticist could give would be not to marry anyone who is known to be a relative. Ironically Charles Darwin married his cousin, Emma Wedgewood! Eugenics To these small benefits of Mendelian genetics should be added the problems created by eugenics. Eugenics was invented by Francis Galton, another cousin of Charles Darwin. Galton was an eccentric who attempted to apply contemporary evolutionary theory to human beings. For example he noted that couples who were romantically linked, tended to lean towards one another, whereas couples who were not leaned apart. By placing pressure sensors under the legs of dining
  • 4. 4 chairs, he hoped to measure the physical attraction between guests at his dinner parties! Galton suggested that human beings should be “bred” for desirable characteristics such as intelligence, physical fitness and good looks. The premise of eugenics is that humans have been progressing as a result of natural selection and that this process needs help if it is to continue. His ideas became increasingly popular during the early part of the twentieth century, and were enthusiastically adopted by the Nazis (but did not end with them). One popular idea was that people with “low intelligence” had more children and therefore, (assuming that “intelligence” was genetically based) the world would soon be overrun with stupid people. Sterilisation of the “mentally ill and retarded” was one consequence of eugenic thought, and this continued in Sweden until comparatively recently. The other side of eugenics was “positive eugenics” the idea that as an alternative to sterilising or murdering the “genetically inferior”, people with “good genes” could be encouraged to have more children. Margaret Thatcher supported this policy with tax breaks and benefits for academics to encourage them to have more children. The problem here has still not been resolved. Eugenics has largely gone out of fashion, except among extreme far-right groups, but the problem remains: Do humans obey the same natural laws of genetics as animals and plants? If so, then eugenics is essentially correct, and serves the greater good, however abhorrent it appears. If humans do not obey these rules, then why not? Why should humans be shaped solely by nurture, while other organisms are shaped by nature? The environments in which humans live have changed massively in the last few thousand years (a very short time in evolutionary terms). New evolutionary pressures present themselves to humans every generation: new environments, new diseases, new diets, new lifestyles, new types of social interaction etc., and so humans will have difficulty adapting. Who knows what abilities we will need in 10,000 years time? If a gene slightly increases the likelihood of a twenty-first century human being mentally ill, alcoholic or having a low IQ, can we say with any certainty that this gene does not and cannot provide any benefit to humans under any circumstances, now or in the future? It should be remembered that such genes increase the likelihood of people developing a trait such as alcoholism, that only a tiny minority of (say) alcoholics will have this gene, and it is probably misleading to view it as a gene “for” alcoholism at all. Very few cases of “genetically determined alcoholism” are likely to be observed in strict Muslim countries. There is no reason to believe that genes for personality traits conflict with ideas of free will. What relevance would the ability to score highly on IQ tests have had to our stone-age ancestors? Research has shown that Australian Aborigines have better spatial memory skills than Europeans. Until recently, the aboriginal lifestyle required them to navigate for miles, find sources of food and water etc. in what appears to us to be a featureless landscape. Given many generations, humans could evolve who were perfectly suited to modern urban life. Currently this environment seems better suited to rats and pigeons than humans. Darwin’s concept of “fitness” means nothing by itself, unless reference is made to the environment in which the organism lives. Organisms have adapted to live in virtually every environment on earth. The nature/nurture debate is based on an artificial distinction. Many genetic disorders can be cured by conventional medical techniques (gene therapy has been largely unsuccessful so far). The hereditary disease phenoketylnuria can be cured if children with the disorder keep to a diet low in the amino acid phenylalanine. Congenital deformities can be corrected by surgery, hormone imbalances with hormone therapy etc. There is no reason why a person with a gene “for” alcoholism should feel that they must drink themselves into the grave, or a person whose particular gene/environment combination have predisposed him to violence, cannot chose or be helped to avoid committing violent acts. Rather than attributing undesirable behaviour to genes, or the environment (and thereby seemingly excusing it), all that can really be said is that human behaviour is unpredictable and everyone has a different personality. Christians have traditionally stressed the importance of teaching and religious instruction to guide people away from sin, but have never denied that different personality types exist or that different people are exposed (and predisposed) to different temptations.
  • 5. 5 Plant and animal breeding with the aid of Mendelian genetics It is a widely held view that modern genetics has allowed scientists to improve crop plants and domestic animals, and thus help to feed the world. This idea needs to be scrutinised carefully. To begin with it is not clear how much modern plant and animal breeding owes to Mendel and Darwin. Since the dawn of agriculture, farmers have been using their healthiest animals for breeding and their healthiest crops for seed. In addition a lot of “breeding” would have occurred unintentionally: animals and plants which were genetically unsuited to the conditions in which they were grown, would naturally remove themselves from the gene pool, by dying before they reached maturity. Admittedly the precise processes by which traits were inherited was not understood. Farmers in the seventeenth century would mate cattle in front of a white wall if they wanted white calves. The story of Jacob, Laban and the speckled goats describes a similar belief. It is likely that this belief arose because many farm animals do not breed true for coat colour. White goats can be carriers for a gene that causes a speckled coat. By the time of the agricultural revolution, however, most of the techniques of modern plant and animal breeding were already in use in some form. Farmers were crossing different breeds of livestock to obtain hybrid vigour in the offspring. Prize bulls and racehorses were being intensively inbred to produce “thoroughbred” animals. After WW2, modern genetics was applied to crop breeding. Fertilisers, insecticides, fungicides and herbicides had become available. The resulting changes in agriculture became known as the green revolution. New varieties of cereals and other crops were produced. It was firmly believed that through the application of Mendelian genetics, crops could be improved and made higher yielding. Results seemed promising at first. Crop yields rose, but the new crop varieties were only high yielding under certain conditions. Many of the cereal varieties had been bred into dwarf forms, the logic being that dwarf cereals would transfer more of their energy into producing grain and less into producing a long stalk. This meant that they were unable to smother weeds effectively, and so herbicides were required. In a similar way, they needed high inputs of fertilisers, and pesticides, because the new varieties lacked the ability to grow in soil without high levels of readily soluble nutrients. Also, the crops had been bred in the presence of pesticides and fungicides, and consequently the crops lacked natural disease and pest resistance. The use of herbicides that killed broad-leafed plants ensured that the new cereal varies needed to be grown as monocultures. In many parts of the world, cereals were traditionally grown as intercrops. For example, rows of cereal were alternated with rows of beans. The result is that yields of the individual crops are slightly reduced, but the total yield of both crops is high. Attempts were made to breed disease resistant crop varieties. The approach was to identify plants with genes for pest and disease resistance. Mendelian techniques were then used to see how the resistance genes were inherited, and a strain was bred with these genes. It was not possible at that time to know the precise DNA sequences involved, but the Mendelian techniques allowed inferences to be made about the genes involved. Production of F1 hybrids was increased. These are the first generation resulting from a cross between two inbred varieties, for example, a high yielding variety with poor disease resistance and a low yielding, hardy variety with good disease resistance. The resulting crop is highly uniform and has the best characteristics of both parents: disease resistance, and high yield. Seed can’t be saved from F1 hybrid crops, because the resulting plants do not breed true, much like Laban’s goats, they would be a mixture of genetic types, many of which would have one or both of the undesirable traits (low yield, low disease resistance) of their grandparents. It was believed that if all farmers were pursuaded to grow these “improved” crop varieties, then the pests and diseases could be eradicated. The problem was that the disease resistance didn’t last. Within a few years, the new crop varieties succumbed to new strains of disease and to pests. It is now suspected that some plant diseases are in competition with one another, and that many diseases may be living on our crops, but their effects are barely noticable because they are
  • 6. 6 suppressed by other diseases. When one disease is temporarily eradicated, another takes its place. The plant breeders’ response to this has been to produce more “improved” crop varieties, but the new resistance rarely lasts long. Governments and the EU produce lists of “approved” crop varieties, which must have been through an expensive trials period to test their yield and performance. Growing unapproved crop varieties is discouraged or forbidden. The long term effect has been a massive reduction in the genetic diversity of the worlds crops, as farmers who have traditionally saved their own seed, switch to green revolution “improved” crop varieties. Around 40% of the crop varieties in existence in 1945 are now extinct. Despite all of the effort into improving crops and improving farming methods, farmers now lose a higher percentage of their crops to pests and disease than they did in 1945, and expenditure on pesticides has increased accordingly. A similar approach has been applied to the breeding of animals. Mendelian genetics was used to breed faster growing animals, producing more meat, milk and eggs. Animals are now rated for “genetic merit” a measure of their growth rate, productivity and disease resistance, and their breeding is described as “genetic progress”. Hybrid animals are commonly produced, and artificial insemination means that one male animal can fertilise thousands of females. Increased international trade and subsidies has allowed farmers to buy in high protein feed such as soybeans to feed to animals. Intensive animal production units have replaced traditional mixed farms. Previously animals had been valued for their ability to produce something of value (i.e. meat, milk, eggs, wool, etc) from something of no direct use to humans (i.e. grass or waste food), while producing manure. Now they are increasingly seen as a source of a single product. One consequence of this approach is that animals have been bred with a requirement for a rich diet. Dairy cows fall victim to mastitis, lameness and a host of other illnesses if their diet isn’t adequate. Some dairy cows now convert over a 1/3 of their body protein into milk protein every day. The principle result of dairy cow breeding programs has been extremely large cows with huge appetites. Veterinary bills, use of antibiotics etc. have all increased. The genetic basis of pest and disease resistance In the long term, these attempts to improve crop and animal disease resistance using modern genetics have been largely unsuccessful. Paradoxically this is because the plant breeders have failed to grasp the implications of modern evolutionary genetics. Pest and disease resistance in plants and animals can be seen as a low-level war between a pest or disease and the plant or animal. The plant or animal evolves a genetic defence against the pest or disease. Often this is a chemical that kills the pest or disease. This creates a situation in which there is strong evolutionary pressure on the pest or disease organism: Only a tiny minority of the pests or diseases will be able to attack the plant or animal, but these will quickly spread as soon as the necessary evolutionary jump has been made. The plant or animal will then be under similar evolutionary pressure to evolve new defences. This raised a question for evolutionary genetics: Insects can be born, grow up and reproduce in a few days. Bacteria can go through many generations in a single day? How then do oak trees, humans and other long-lived species evolve fast enough to keep up with the diseases and pests? One possible answer was the Red Queen hypothesis, formulated by Leigh Van Valen10. According to the Red Queen hypothesis, long-lived organisms are “running just to stand still” (like the Red Queen in Alice through the Looking Glass). Any defence against pests and disease which the animal or plant is born with will be obsolete by the time the organism reaches maturity, as the pests and diseases will have developed a counter mechanism. Sexual reproduction ensures that the genes coding for various aspects of the defence mechanism are swapped around every generation, creating radically new and different defences, by mixing old ones. Long-lived, multicellular organisms are more likely to reproduce sexually than short lived and unicellular organisms. Crop plants, which are produced, asexually, e.g. potatoes, often suffer from serious disease problems.
  • 7. 7 By analogy, imagine a village plagued by burglars. All of the houses are kept locked at night, but every year some of the houses still get burgled because ingenious burglars found a way to pick or break the lock. Some locks are stronger or less easy to pick than others, and there are many types of lock: padlocks, combination locks and electronic locks for instance. Now imagine that the local police visited the village, observed that this year, houses with a particular type of padlock were less likely to be burgled. The police tell everyone in the village to get this type of padlock on their doors. The following year the burglary rate drops dramatically, but the year after, one of the burglars returns with an improvised lockpick and manages to burgle most of the houses in the village, defeated only by a few of the locks. The police conclude that everyone in the village should obtain locks that are precise replicas of those on the few secure houses. Two years later, virtually every house in the village gets burgled. The most important thing about locks is that they are all different. The villagers should have used as many different types of lock as possible and change them every year. Returning to animal and crop defences against disease, the best strategy for plant breeding is to encourage as much diversity as possible, so that new crop or animal diseases or pests won’t suddenly spread around the world in a single growing season. Breeding programs should be decentralised and farmers should be actively encouraged to save seed. Research has shown that planting a mixture of genetically-diverse rice varieties increases yields by 89% and reduces disease by 98%13 There is another reason for encouraging diversity: every farm has a different soil, different climate, different pests and different farming methods. Centralised plant and animal breeding programs cannot hope to produce varieties suited to all these different conditions. The environment also varies spatially, and wild plants often form genetically distinct subpopulations adapted to local conditions11. When an “improved” crop variety performs poorly, this is usually attributed to a shortage of the right nutrients in the soil, or to the farmer’s failure to use the right pesticide. In other words, the environment must be modified to suit the “improved” crop. One effect of the green revolution that is not often mentioned is micronutrient malnutrition. As has been mentioned, the green revolution caused many people in the third world to switch to a diet consisting almost entirely of cereals. In addition to this, many of the green revolution crops are now known to be low in trace elements such as iron and zinc. The massive problem of zinc, iron and vitamin A deficiency in the third world is almost entirely due to green revolution crops and farming methods7 8. Common, tropical edible weeds such as mustard and bathua used to provide many small farmers in the third world with their vitamin A requirements, but herbicide use has led to their eradication. When the total yield of animal products, annual crops, fruit, edible weeds etc. is considered, many traditional third world farms yielded 20 tonnes of food per hectare, and in addition, the wide variety of crops grown provided security in the event of one crop failing. The most intensive cereal monoculture struggles to produce 10 tonnes of grain per hectare8. The problems that the plant and animal breeders set out to solve have, by and large, got worse. Yields have improved, but it is not known how much of this can be attributed to the breeders. As I have tried to show plant and animal breeding has not actually taken much notice of recent developments in evolutionary genetics, and in any case, the basic philosophy of modern plant and animal breeding was in operation before Darwin, Mendel, Watson and Crick. Plant and animal breeding has changed over the last century, but generally this change has been a move towards greater centralisation, fewer crop and animal varieties, and greater use of hybridisation. None of which can really be attributed to any of the aforementioned scientists. Plant and animal breeders still act as though they believe that a perfect plant or animal could be produced if all of the “inferior” genes could be removed from the gene pool, and replaced by “superior” ones. This “superiority” is meaningless if the environment in which the species are bred is not considered. The result has been inbred plants and animals bred for farming systems, which have in turn been modified and homogenised to suit the crops and animals. These farming systems are often
  • 8. 8 expensive, polluting and unsustainable (meaning, by definition, that they will have to change in future), but the loss of diversity makes future breeding of crop plants more difficult. Genetic engineering and cloning Press releases about new genetically modified crops or cloned animals, usually say something to the effect that “Scientists believe that genetic technology/animal cloning will result in new crop/animal varieties which will feed the world, resist all known diseases, cope with drought/saline soil/pollution etc.” “Scientists” in this context invariably means molecular geneticists, or more likely public relations or marketing executives interpreting the latest discoveries in molecular genetics. Often this is simply a high tech version of the old Mendelian methods: identifying genes for high yield, disease resistance etc. using molecular techniques (DNA sequencing etc.) and then breeding them into new animal and plant varieties. The basic philosophy remains the same, but the technology is more sophisticated. More recently has been the promise that genes from a wide range of organisms can be artificially introduced into crop plants and animals, in order to “improve” them, the so called genetically modified or genetically engineered (GE) varieties. Molecular genetics is hailed as the solution to agricultural problems, to medical problems, and to political and social problems such as world hunger. However, the molecular geneticists often seem remarkably naïve about these issues. Golden rice (so called because of its yellow tinge) is a GE strain of rice containing genes from daffodils. Golden rice contains additional vitamin A, iron and zinc, and has been hailed as a solution to the micronutrient malnutrition problems of the third world, by the Rockerfeller Foundation. Much has been made of the problem of blindness caused by lack of vitamin A. What has not been mentioned often is that this is a man made problem (as explained earlier). Ironically, the Rockerfeller Foundation played a large part in creating these problems during the green revolution! Golden rice doesn’t actually contain much available vitamin A. An adult eating a balanced diet (so as not to get other forms of malnutrition) could reasonably hope to get about 5% of the recommended daily dose of vitamin A from golden rice. In this respect, “golden rice” is a fairly poor source of vitamin A, compared to green vegetables9. It should also be remembered that the object of the genetic engineering was to put extra vitamins and minerals into white (polished) rice. Brown (wholegrain) rice already contains vitamin A, along with a wide range of other vitamins and minerals, but these are removed when the rice is processed into white rice. Genetic engineers believe that they can overcome natural limits to evolution, (which almost certainly exist) by “redesigning” plants and animals with new genes. This is theoretically possible, but there is little evidence that it can be achieved in practice. The most widely successful application of genetic has been herbicide resistant crops. Here a plant is being bred for an environment with large amounts of herbicide in it. GE crops are sometimes presented as a solution to declining crop diversity, but traditional crop varieties are becoming extinct far faster than the new, untested GE varieties can be developed. GE crops are often common varieties with one new gene added, so the increase in diversity is not great. Another problem is the trend towards patenting of genes, which has gone hand in hand with GE technology. This makes seed saving illegal. The biotechnology companies have even developed technology to ensure that seeds from GE crops will be sterile, or won’t grow effectively without a patented agrochemical12 Cloning farm animals, we are told will sort out disease problems “once and for all”. The logic seems to be that sex is a problem in animal breeding because the “good genes” of one animal have to be contaminated with the “inferior genes” of its mate. It is also claimed that cloning can save endangered species. Cloning of animals is no quicker than natural reproduction and does not address the main reason for present day extinctions, which is habitat destruction. The same problems apply to the new genetic technology, as to the Mendelian techniques: it is assumed that genes can be found which will provide high yields in all conditions, and disease
  • 9. 9 resistance now and in the future. The basic philosophy remains the same, but the technology is more sophisticated. Conclusions The theory of evolution by natural selection states that all organisms have different sets of genes that code for physical traits. Every generation, some individuals of a species reproduce more than others, because their genes give them an advantage in their natural role and environmental conditions (known as the ecological niche). Over time this ensures that organisms change and diversify to fill the range of niches. Natural selection requires inherited variation and selection by the environment (the physical environment and the other species with which the species in question interacts). As we have seen, the selection pressures exerted by short-lived species (insects, bacteria, fungi etc.) on long-lived species (multicellular animals and plants) are continually changing. The concepts of “good genes” and “bad genes”, “high genetic merit”, “Evolutionary progress” etc. are therefore not very useful, as genes are only good or bad for a particular environment, and no organism is evolving “towards” anything. Eugenics, Mendelian plant and animal breeding, genetic engineering and cloning all tend to follow a model of evolution that emphasises “progress” but not diversity. All assume that evolution will work better if it is guided by human intellect. It is clear that this is not “value free” science, and the public are perfectly entitled to question the values of the scientists. When GE technology is used to attempt to solve man-made problems, it is right to ask why the root causes of the problem are not being addressed. When an agrochemical corporation engineers a soyabean for use with the corporation’s own herbicide, we should ask if this is in our best interests. When anyone is labelled as “genetically inferior”, and their genes treated as a burden to future generations, we should ask who is doing the labelling, and what kind of society, they regard as “normal” for humans to live in. When plants, animals and genes are patented, merely because a scientist has “read” their DNA, the Christian view that all living things are God’s creation makes a lot of sense. There is nothing wrong with seeking the truth through science, as long as it is understood that the truth is never totally obtainable. Scientific theories begin as heresy and end as myth. Leaping to conclusions from a young science like genetics is not wise. Technology depends on the questions asked by the scientists, and the reliability of their conclusions. If the questioning is biased, then the technology will not serve everyone. If the conclusions are wrong, then the technology will not work. The job of scientists is to question the conclusions. The job of religion and philosophy is to question the questions. 1 Charles Darwin, The Truth 2 Desmond King-Hele. Doctor of revolution Faber (1977) 3 T. McKeown & R.G.Brown Medical evidence related to English population changes in the eighteenth century Population studies ix (1955) 4 Richard Dawkins The Selfish Gene 5 Stephen Jay Gould Hens Teeth and Horses Toes 6 Stephen Jay Gould The Panda’s Thumb and other Essays 7 Hungry for a new revolution New Scientist 17th October 1997 8 Vandana Shiva Monocultures of the Mind 9 Vandana Shiva Address to International Forum of Organic Agriculture Movements, Basel 2000 10 Van Valen L. "A New Evolutionary Law", Evolutionary Theory 1, p. 1-30. 11 Mithen, R, Raybould, AF, Giamoustaris, A Divergent selection for secondary metabolites between wild populations of Brassica oleracea and its implications for plant-herbivore interactions. Heredity 75 472-484 12 US patents US 5,777,200; US 5,847,258; US 5,767,369; US 5,689,044; US 5,654,414; US 5,789,214; US 5,614,395; US 5,650,505 and US 5.804,693 13 New Scientist, 'Triumph for Diversity', 19 August 2000, p.21.