janw@inmet.UUCP (09/06/86)
>[carnes@gargoyle.UUCP ] >[Jan Wasilewsky] >>All these were widely predicted in the 60's for the 70's and the >>80's [and did not come to pass]. >Again I would ask Jan to cite chapter and verse, explain what was >predicted and what actually happened, and explain why some mistaken >predictions invalidate all such predictions. O.K. : "The battle to feed all of humanity is over. In the 1970's the world will undergo famines - hundreds of millions of people are going to starve to death in spite of any crash programme embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate" Dr. Paul H. Ehrlich in *The Population Bomb*, quoted (with approval) in "The Hunger to Come" by John Laffin, Abelard-Schuman, London, New York, Toronto, 1971, p.20. The seventies have come and gone. There have been famines - local ones, like in Cambodia, due precisely to "crash programs" launched by some governments. Hundreds of millions have *not* died, and the world as a whole was fed *better* than before. And the world death rate kept *falling*. The foolish prediction was not long-term, it was made on the very threshold of the 70's. Nor was Ehrlich a maverick. You ask why this should invalidate newer predictions. Suppose you drank from a pool and were poisoned. Before drinking again from the same pool, you would require a drastic cleaning and *test- ing*. Same with the predictions of Dr. Ehrlich and the whole academic pool of soft-core sciences he represents. These sciences have yet to earn their spurs in prediction-making. Meteorologists can only predict a few days ahead, and that without certainty - but they don't *claim* more. Ehrlich & Co., unfortunately, do. The problem is not that people make mistakes in predictions. The problem is that the same people, and their disciples, don't even wipe the mud off their faces, but continue making similar pred- ictions, using similar methods, and wrapping themselves in the mantle of "science". As *science fiction* this would be unobjectionable. Science fic- tion scenarios of the future are useful thought experiments. But before one *acts* on the basis of these scenarios, one should consider other, equally unscientific, but equally possible, maps of the future. >>The above is full of "potential", "could" and "would". One could >>just as easily draw a scenario in which too *few* people would >>prove perilous. E.g., a new virus killing off everyone but >>bearers of a rare immunity trait. The more people, the more >>chance that a viable remnant survives. >But the more people, the greater the chance of a virulent pandemic in >the first place. The high population density, unsanitary conditions, >malnutrition (which reduces resistance to disease), and ecosystem >degradation associated with overpopulation provide a fertile medium >for the spread of infectious diseases. The more people, the greater chance of infection - true as far as it goes - i.e., other things being equal. But they aren't, and they far outweigh mere numbers. The Black Death killed off a third of European population in the middle of the 14th Century, and recurring epidemics of the next 100 years decreased population by half again. Nothing like that has happened since, in spite (or because) of enormous increase in density: tenfold compared to the pre- plague times, thirty or more times compared to the 15th century. As for the other negatives like antisanitary conditions and mal- nutrition - making them a monotonic function of population begs the question. Again, Europe is more sanitary now than in the 13th Century; and it was *less* sanitary in the 15th century - after a drastic fall in density - than it was in the populous 13th. Had Europe controlled its population in the great growth period of 9th to 13th centuries, it would not have mollified the plague - but it would have left post-plague Europe depopulated to the extent that its civilization might have been unable to rebound. As for the ecosystem: yes, wolves and bears don't roam the suburbs of London as they undoubtedly did once. Even the deer of Sherwood forest are gone, through the exploits of Robin Hood and his successors. This does not seem to "provide a fertile medium for infectious diseases". Ecosystems *change*. Fewer deer, more horses; fewer horses, more ponies, canaries and guinea pigs. There is no reason whatever to think that human-caused changes are somehow less legitimate or more harmful than others. Change works *against* many infections, as the infectious agent may fail to adapt to the new environment. The ecosystem of Europe may be the poorer by the loss of the Ano- pheles mosquito; but people don't get malaria. In areas where the 60 cute species of this valuable genus are not endangered, 100 million people catch malaria every year, 1 million die of it. >Our ancestors survived for millions of years (which saw extreme >climatic changes) at population levels far lower than the present >5 billion (probably much less than 1 million, if memory serves). Our ancestors survived by diversity and competition: individual groups died out from diseases, but others were not affected by this. Since the emergence of the global civilization with intensive contacts between all its parts, the emergence of a virus or germ that could wipe out most of us is a real possibility. It may or may not be *probable*: I don't have data to estimate it, and I doubt anyone has. But neither is there data to appraise the perils of high population: these are equally imaginary scenarios. >I don't know if there has been any species whose extinction was >primarily due to infectious disease. Nor do you (or anyone) know there aren't. But species *do* get extinct when their numbers are sufficiently depleted; and it is safe to say infections contribute to that. >The genetic variability of the human population is much less >important in the modern control of infectious disease than the >genetic library found in other species. Yes, but I was speaking of our insurance against disaster, not day-to-day disease control. Science has not licked AIDS yet; meanwhile we are lucky that it is not more infectious than it is *and* that some people are immune to it. This last *is* a matter of genetic variablility, and may one day be our last-ditch defence. >Many medicines have been developed from other species, some exam- >ples being quinine, penicillin, streptomycin, tetracycline, and >cytarabine. We have barely begun to tap the potential of other >species to provide medical benefits -- a strong argument in favor >of species and ecosystem preservation (especially in tropical >forests), which in turn is a strong argument in favor of human >population control. We do reduce the number of species and ought to preserve them. That much is granted. But: (1) The reduction depends on the current technology much more than on the population numbers. E.g., space-based industries wouldn't disturb any species. (2) Species (or their genetic material) may be preserved artificially in lab conditions. (3)Assuming that the chances to derive new medicines from other species are proportional to the number of species, they are only reduced negligibly by the loss of a few thousand of them. (4) The biotech industry is starting to produce artificial genetic variations that should diminish our dependence on those naturally occurring. (5) These useful drugs are developed *from* other species *by* Homo Sapiens. They are a product of two factors. If "the fewer species the fewer drugs" is true (in the abstract) then it is quite as true that the more people the more drugs. Since popula- tion growth is greater, by many orders of magnitude, than species depletion, we gain by the process. Not all people make these discoveries, to be sure, - we have "just started to tap their potential". Jan Wasilewsky