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Although they comprise only 37 % of the world' s total land area, Europe and Asia make up 79% of the population. This implies a much greater population density on the whole. For countries on these two continents than for others, Antarctica, for example, contributes 9% to the total land area, but 0% to world population. Similarly q the continents of North & South America, Africa, and the regions labelled Oceania, each support much lower populations than might be expected if land area is the sole factor controlling distribution. obviously, there must be other critera which influence human distributions.
Not all of the land' s surface is amenable to development and settlement by mankind. The world' s mountain ranges, for example are too hostile to allow major population centers to develop. While it is not impossible to live there, they can only support a limited number of people. Another inhospitable type of surface would be desert. Once again, due to adverse conditions, it is hard for people to live in large numbers in the desert.
Climate is a factor which should not be neglected in the analysis of this problem. It was alluded to in deserts, as they are, in part, climate-induced. However, there are large areas which, even if they did not count -as desert (or arid), would be uninhabitable. I refer, of course, to Greenaland and Antarctica. Both of these are in the strictest sense, deserts; neither receives much precipitation in the course of a year. However, the stronger influence in these areas is temperature. They are each too cold to support the complex array of plant and animals, mankind needs in order to flourish.
Food supply, and some raw materials, are also linked both to climate and to human population density. Where conditions favor the development of abundant nutritional sources and raw materials such as wood, man is likely to be found, and in great numbers. In areas where these commodities are scarce, man will not be so evident.
While these are not the only parameters which control the distribution of human populations accessibility. Climate, and availability of the basic necessities of life are important considerations. On continents where these combine favorably, man has settled in great numbers. Where these are not as well developed, mankind tends to be more thinly distributed. Europe and Asia seem to have the closest to optimum combination, while Antarctica appears to be uninhabitable.
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