When I started this weekly feature a month ago I was worried about finding enough new material each week. Instead I find myself deluged with enough news stories and journal articles to do an entire years worth of news updates. If theres any topic relating to overpopulation on which youd like to hear about the latest research, email me and let me know.
The 20th century has seen numerous improvements in health and the result is a much larger population. But exactly how much larger is the population because of these changes in health? In an article in the September 1996 Population and Development Review, Kevin M. White and Samuel H. Preston underscore just how significant the change has been by looking at what the population of the United States would be if death rates in 1900 had remained stable.
White and Preston offer four scenarios of population size in 2000. The actual estimated population in the U.S. in 2000 is 276 million persons. If, on the other hand, death rates at all ages had been fixed at 1900 levels, the population in 2000 would only have been 139 million people.
Most of the difference is accounted for by reducing childhood death. When death rates for 0-14 are fixed at 1900 levels but death rates for other age groups vary at actual rates, the population jumps to 186 million.
When death rates for ages 15-49 are fixed at 1900 levels, the population jumps to 225 million, and when death rates for ages 50+ are fixed at 1900 levels the population jumps to 258 million.
Although decreasing infant mortality and early childhood death have been of overwhelming importance, the population would still be only half of what it is today had it not been in improvements in mortality rates for those aged 15 and over.
Sticking to food production for the moment, one of the refrains I hear constantly from people skeptical of claims of increasing food production is that current farming techniques are unsustainable because they rely on manmade pesticides and fertilizers. I happen to think that claim is spurious, but it is also largely irrelevant.
Almost every week a new major discovery is reported in efforts to create more effective farming technologies which often turn out to be far more “environmentally friendly” than current methods. In July, for example, it was announced that Colorado State entomologist Louis Bjostad has made significant progress in developing a natural way to rid corn of the Western corn rootworm, responsible for up to $1 billion in annual crop losses.
Bjostad discovered the rootworm eats corn because of carbon dioxide given off by corn roots. He and his researchers are working on pellets and granules of yeast, baking soda and other materials which could be placed in corn fields which would confuse the rootworms by giving off carbon dioxide. If it works, Bjostads discovery would not only be safer but far cheaper than using conventional pesticides.
Bjostad plans to do two more years of field tests to identify which compounds and mixtures are most effective in dealing with the rootworm.
One of the major limiting factors of population size is food. Although his predictions of impending doom have so far proven wrong, Paul Ehrlich is right that if human population outstrips food production, the result would be a disaster. The question becomes, how likely is that disaster to occur? Not likely according to John Bongaarts.
Bongaarts is the author of “Population Pressure and Food Supply,” published in the September 1996 issue of Population and Development Review. Bongaarts analyzes trends in world food production from 1962 to 1989 using Food and Agricultural Organization data.
After a lengthy analysis of the any facets of the change in food production over that period and reasonable expectations about future changes in food production, Bongaarts concludes,
Although any projection to the middle of the next century must be regarded as speculative, on the whole the above illustrative scenario for 2050 appears achievable. Recent short-term projections to 2010 or 2020 based on econometric models by the World Bank (Mitchell and Ingco 1995), FAO (Alexandratos 1995), and the International Food Policy Research Institute (Agcaoili and Rosegrant 1995) also foresee no major obstacles to continued expansion of the food supply. It is therefore likely that serious and persistent global food shortages can be avoided, provided governments vigorously pursue efforts to improve economic policies and facilitate the dissemination of new technology and investment in research and human resource (Bongaarts 499).
Although Africas collective problems are still enormous (witness recent events in Rwanda, Burundi and Zaire), but there are indications that at least parts of Africa may be turning the tide. MSNBC recently ran a multi-part series examining the state of Africa. Aside from South Africa, the continents bright spot is East Africa.
Specifically democracy appears to be blooming East African states. Uganda and Malawai have embraced democracy and 10 percent economic growth in 1996. Scott Moore, MSNBC reporter, notes that Tanzania and Eritrea appear to be remaining stable after years of civil war and other problems.
And Kenya appears to be on the road to democratization as well. Strongman president Daniel arap Moi facing serious economic problems is lifting long-standing policies of harsh repression of pro-democracy demonstrators and will be meeting with opposition leaders to discuss political reform.
According to Moore, both Tanzanian and Uganda have benefited by dumping socialist command economies and central planning and embracing the free market. In Uganda Yoweri Museveni abolished monopolies and launched a privatization program which has increased both industrial and agricultural production. Tanzania has gone so far as to create a stock exchange.
Bottom line — freedom works.
With the proliferation of the Internet, most of the data and other information regarding population are now conveniently found on the web. So now when someone emails me, as often happens, that my population numbers are a crock, I can point them to the US Census Bureaus on-line estimate of world population through 2050.
There are two interesting things to note about these figures. The first, of course, is that the mid-year population projection for 2050 is 9.3 billion people — far lower than some of the irresponsibly high numbers which are often tossed around as if they are inevitable.
Second, the actual world population total could be far lower. Consider, for example, that from 1986 to 1996, the average annual growth rate declined by .28 percent — close to a .03 percent decline per year. In fact since 1970 the world has experienced an average .255 percent decline each year. But for its projections, the Census Bureau assumes only a .02 percent drop each year.
Of course, on the other hand even small decreases in this rate could drive the population in 2050 far higher, but so far all of the available evidence is consistent with a continuing fall in worldwide fertility rates and thus population growth rates.