Home > Malthusian catastrophe
A Malthusian catastrophe, sometimes known as a Malthusian check, is a return to subsistence-level conditions as a result of agricultural (or, in later formulations, economic) production being eventually outstripped by growth in population. Theories of Malthusian catastrophe are very similar to the subsistence theory of wages. The main difference is that the Malthusian theories predict over several generations or centuries whereas the subsistence theory of wages predicts over years and decades.1 Traditional views
In 1761, Robert Wallace published Various Prospects of Mankind in which he argued that progress would eventually undo itself by overstocking the world with people. Thirty-seven years later, Thomas Malthus published his now famous Essay on the Principle of Population. In it, he predicted that population growth would eventually outrun food supply. This prediction was based on the idea that population, if unchecked, increases at a geometric rate, whereas the food supply could only grow at an arithmetic rate. Mathematically, any increasing geometric sequence (e.g. 1, 3, 9, 27, 81) will eventually overtake all arithmetic sequences (e.g. 10, 20, 30, 40, 50). The resulting decrease in food per person will eventually lead to subsistence-level conditions. According to Malthus, the catastrophe can only be prevented by self-restraint or vice—which for him included contraception and abortion.
Malthus did not give a time frame for his catastrophe. Thus far, population growth has been essentially geometric as Malthus predicted. The Malthusian catastrophe, however, has not occurred, principally because food supply growth has also been roughly geometric, not arithmetic. Furthermore, the widespread use of contraception and abortion (Malthusian vices) have, as Malthus said they could, restrained population growth significantly. In fact currently food supply per person is several times higher than when Malthus wrote his essay.
2 Neo-Malthusian theory
Neo-Malthusian theory argues that unless at or below subsistence level, a population's fertility will tend to move upwards. Assume for example that a country has 10 breeding groups. Over time this country's fertility will approach that of its fastest growing group in the same way that
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will eventually come to resemble
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regardless of how large the constant a is or how small the constant b is. Under subsistence conditions the fastest growing group is likely to be that group progressing most rapidly in agricultural technology. However, in above-subsistence conditions the fastest growing group is likely to be the one with the highest fertility. Therefore the fertility of the country will approach that of its most fertile group. This, however, is only part of the problem.
In any group some individuals will be more pro-fertility in their beliefs and practices than others. According to neo-Malthusian theory, these pro-fertility individuals will not only have more children, but also pass their pro-fertility on to their children, meaning a constant selection for pro-fertility similar to the constant evolutionThis article is about biological evolution. For other possible meanings, see Evolution (disambiguation). Evolution generally refers to any process of change over time. However, in the context of the life sciences, evolution is a change in the genetic makeary selectionIn the context of evolution, certain traits or alleles of a species may be subject to selection. Under selection, individuals with advantageous or "adaptive" traits tend to be more successful than their peers reproductively--meaning they contribute more o for beneficial geneDNA and to a chromosome (right). Introns are regions often found in eukaryote genes which are removed in the splicing process: only the exons encode the protein. This diagram labels a region of only 40 or so bases as a gene. In reality many genes are muchs (except much faster because of greater diversity). According to neo-Malthusians, this increase in fertility will lead to hyperexponential population growth that will eventually outstrip growth in economic production. Neo-Malthusians argue that although adult immigrants (who, at the very least, arrive with human capitalHuman capital is a way of defining and categorizing peoples' skills and abilities as used in employment and otherwise contribute to the economy. Many early economic theories refer to it simply as labour, one of three factors of production, and consider it) contribute to economic production, there is little or no increase in economic production from increased natural growth and fertility. Neo-Malthusians argue that hyperexponential population growth has begun or will begin soon in developed countries.
