When one discusses problems concerning natural resources and threats to the global environment, one has to realize that for the first time in the history of earth, one species is capable of ordering at will the whole biosphere. But that is a reason to property of human species, when early human species into the biological arena 3 or 4 million years ago, they behaved as another fairly insignificant ecological link in the ecosystems. As early partakers, Sinanthropus, Pittecanthropus, Neanderthalensis or early Sapiens did not imply any excessive threat neither to the ecosystems nor to the environment. Since then, man has exhibited an unparalleled biological success and ecological dominance. There has been an explosive development of the human population which has resulted in a transformation of the landscape, eradication of much of the biological diversity, a global alteration of the atmosphere and deterioration of high altitude of ozone layer, acidification of large areas and the global spread of persistent chemicals like DDT, MPCB. These large scale alterations by human activities hardly ever had any counterpart in the history of the earth. Dramatic changes have occurred previously such as beyond the pretentious time, 65 million years ago, when the dinosaurs and the large number of other species died out. But such environmental disasters was not caused by one single species as the case is today. How has this single species of Homo sapiens acquired this ecological dominance? That is a theme I will try to discuss in my presentation today. When the Swedish biologist, Linneus 250 years ago, arranged all the species of plants and animals in his "systema nature," it was with some hesitation that it placed the human species under the animal kingdom. Man was an image of God, and superior to other species and, therefore, should be placed above all other species. Few people maintained this view of the human species today. Evidence for the fact that man is a product of organic evolution is provided at all levels of biological research. From paleontology to molecular biology and from that point of view, man is just like all other species of animals and plants. Nevertheless, I am afraid that if we look upon man as a species essentially comparable to other species it is grossly misleading from a biological point of view. But what constitutes the success of the human species? I think the answer is evident. The capacity of the brain which has made it possible with abstract thinking. But more important from a biological point of view is the consequence of this development of the brain. The crucial point is that the human species deviates from all other organisms in one respect, that is the cause of recent evolution. The biological evolution is based on the transfer of information from one generation to the next. All species except the human species are dependent on alterations of the genetic information through mutations for evolution. That, however, is a slow and impractical process where the vast majority of changes constitute worthless mistakes, which have to be eliminated by natural selection. The human species has been able to bypass this time-consuming system with another kind of evolution, that is the cultural evolution, which is based on the transfer of acquired information from one generation to the next. This system is infinitely more selective and efficient than the genetic evolution, which is based on random mutations. The transfer of information in the human society has undergone dramatic change in an extremely short time from an evolutionary point of view. In some 40,000 years, the human language has developed. The invention of written language and book printing implied revolutionary inventions which enabled a more permanent storage of information than through oral transmission. But perhaps the most revolutionary progress is happening today. With the development of the computer system which enables practically unlimited storage and sorting of information. The efficiency of this cultural evolution is evident when one compass the human society of today with the primitive settlement 10,000 years ago. The dramatic development of the human society during this time is the result so lely of a cultural and not a genetic evolution. The development of science is another consequence of cultural evolution. It is ironic that the replacement of genetic evolution with the cultural evolution has enabled man to get enough insight in life processes to be able to manipulate himself to the genetic information. The accumulation of scientific knowledge has led to inventions which has made it possible to bypass various biological control systems and above all, population birth control by a decrease of mortality and increase of longevity. The net effect can be observed in life expectancy of man as compared to other animals. The British Ornithologist, David Lack saw in his pioneer study of the European bird species robin, that a one year robin had on the average one year left to live, and when he was 2 years, he still had 1 year to live and so on. That means that the life expectancy of the robin in nature is largely independent of age, which means the individuals do not have time to get senile before they died. The situation for modern man is very different. Life expectancy is decreasing with age, because the large friction of the population reach the biological limit for longevity. The same curve, one finds for animals in captivity. It is interesting to note that the people in Rome 400 years after Christ saw the life expectancy which resembled very much more that of the robin than of the modern man. The decrease in human mortality has largely been due to the elimination of infectious diseases. However, with the spectacular development of genetics and molecule biology and new era has emerged in the understanding of human disorders, such as cancer infection and neurological disorders. Behind this development lies some key inventions and observations. The recognition of genes involving cancer induction has opened up the world of cellular signal systems with the identification of genes and proteins that direct the fate of the cells, if they are going to divide to rest or to die. Recent research in genetics and molecular biology have brought to light new techniques and concepts which can be expected to have a wide application for the understanding and treatment of human disorders. It has been possible to link many human diseases to specific genes which can be localized on the chromosome and the DNA and the gene product can be read off and characterized. Among recent breakthrough discoveries, one can mention investigations of the role of those 97% of DNA which does not contain any genes, sometime called junk DNA. In the last few years, at least 8 neurological disorders, some transforms and diabetes have been shown to depend on the expansion of sort repeated DNA sequences which constitute most of this non-coding junk DNA. Another area of genetic research with far reaching implications concern the dynamics instability of DNA. It has been shown that DNA can exhibit high degree of dynamics and instability under certain conditions. This is particularly obvious for cancer induction. In that context, 4 genes responsible for the repair of DNA, so-called mismatch repair have been identified and localized in the human chromosomes. The cells in our body normally repair such defects in DNA, some 10 thousand times a day. Therefore, the loss of this repair capacity results in drastic increase in mutations and the induction of cancer. These and other genetic and biochemical innovations have made it possible to identify individuals who are carrying genes which imply an increased risk for diseases. In many cases, this can be of course beneficial. People carrying genes within their repaired deficiency which particularly give rise to cancer of the large intestine, as I said, can be held to catch a beginning cancer at such an early stage that they can be cured. By this new genetic diagnosis also involve ethical problems. People who are carriers of DNA repaired deficient genes can be expected to be extra sensitive to mutagens and carcinogenic agent and they should not be employed in works when they are exposed mutagens and carcinogens, including tobacco smoke. Another ethical problem concerns the information of persons carrying a genetic defect which acts late in life and where no cure is available. Such a situation applies to Huntington's disease, which is a serious neurological disease inherited as a dominant the age between 40 and 50 years. The new tools for genetic diagnosis implies that more and more people will be able to foresee coming health problems without having any symptoms. An important problem is, who would access to this information? Only the person himself. It is easy to foresee problems for insurance policies. It seems unlikely that insurance companies will be permit their information. But that does not solve the situation. People carrying a genetic defect predisposing for early death, will take advantage of a high life insurance and the cost of life insurance in general will increase dramatically. The new techniques in molecular biology in genetics are heading for a more efficient and selective combat against diseases such as cancer. That development may appear as desirable, but at the same time, it may be emphasized that efficiency of controlling human diseases is one essential course for increasing longevity of the human and their population explosion. In that light, the human cultural evolution must be considered a global ecological disaster. It remains to be seen if the human intelligence and adaptability will be sufficient, to avoid future environmental catastrophe as a consequence of our unique cultural evolution.

Claes Ramel Chairman of the Environmental Committee of the Royal Swedish Academy of Sciences (Sweden, biologist, genetics, genetic toxicology)

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