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Looking at the chart above (where the circle series shows data from year 1975-2004), we see the fetrtility rate in most countries are dropping, except for USA and Russia. Russian income and fertility rate both took a turn around 1996-7, very likely a result of the economic/political transition after USSR collapsed. A few hypothesis regarding Malthus
- There is a clear trend of fertility rate decline over time since 1970s. Is this a result of income growth? or "pressure" (population density/career pressure)
- A noted example is HK, with fertility rate below 1. It is an extremely densely populated urban environment, where there is very little living space (per capita living area is probably lower than 100 sq ft/10 sq m!), working hour is extremely long (many work from 9am to 8pm, for 5/25 days/week). The result may be both psychological and physiological
- This seems to be very strong evidence for Sean Meade's assertion of "Malthus not happening". But I think it is simpler (or more complex) than that. This only shows the self-correcting course of nature. There is a limit for the total number of people our earth can support, given the techonology human being can command at the particular era. When such limit is approached, self-correcting mechanism is "switched on". Such mechanism include famine, war, and gradual correction by natural decrease in fertility, or forced decrease in fertility (China). The only difference between what Malthus predicts and what we have observed. Malthus is still correct. China is able to avoid the Malthus calamity precisely because it took preventative action after warned by Malthus, and got an early lesson in 1959-1961 when policy mistake brought about the calamity earlier than it would have occurred naturally. Had it not been the long period of peace aftger WWII (all wars were local and in relatively small scale. The only areas of major decrease in population due to war is perhaps Indo-China and Korea. So the psychologically/physiologically induced self-correction kicked in because war did not.
- US is a special case, it probably has to do with lower population density (higher space/capita), pro-child environment/culture, secondary effect of the 1950-60 baby-boom cycle, or perhaps hispanic immigration?
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