July 28, 2011 |
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The human population will top seven billion this year—more than double what it was just 50 years ago, experts say.
And these next 39 years are expected to bring about some big shifts among the biggest countries. By 2050, India will have surpassed China as the world’s largest population, growing from 1.24 billion to 1.69 billion as China shrinks from 1.35 billion to 1.3 billion. And Africa’s population will likely have more than doubled by then, with Nigeria slated to catch up to the U.S. numbers. The figures are described in a new report published in the July 29 issue of Science.
Along with sheer numbers, global life expectancy is projected to rise as well: from age 69 worldwide this year to 76 in 2050. By then, nearly a quarter of the world’s population is expected to be over 60—which is about double the proportion that it is today.
"The demographic picture is indeed complex and poses some formidable challenges," including contraception, child mortality and retirement policies, David Bloom, a professor of economics and demography at the Harvard School of Public Health, said in a prepared statement. "Those challenges are not insurmountable, but we cannot deal with them by sticking our heads in the sand."
He and others also assert that we will continue our trend of leaving rural areas for the city. Currently just over half of the world’s population lives in urban environments, but by 2050, that figure is expected to be some 69 percent of the world’s 9.3 billion people.
Some researchers think our tendency for explosive population growth and concentration helped us seize the future from the Neandertals. New analysis, described in another paper published in the same issue of Science, suggests that it was early human’s sheer numbers that pushed aside our predecessors, who had been around for some 300,000 years.
"Faced with this kind of competition, the Neandertals seem to have retreated initially into more marginal and less attractive regions of the continent and eventually—within a space of at most a few thousand years—for their populations to have declined to extinction," Sir Paul Mellars, a professor emeritus of prehistory and human evolution at Cambridge University, said in a prepared statement. He and his co-authors suggest that tools, culture and a diverse gene pool helped our early ancestors be fruitful and multiply. A changing climate might have been the final blow to our close cousins.
As unclear as these ancient dynamics might still be, the future remains even more unsure, noted Bloom and his co-authors on the worldwide population estimates. "The global outlook is greatly complicated by a slew of uncertainties involving, for example, infectious disease, war, scientific advance, political change, and our capacity for global cooperation," they wrote.
Image courtesy of iStockphoto/thehague
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The projected growth could well be mitigated by increased levels of education and birth control, not to mention state mandated family size restrictions, as China has done. Regardless, it behooves us to find more efficient and effective ways to feed all people on our planet. The horrendous famines in Africa today stand in sharp contrast to societies in the West, where obesity is almost as big a problem.
Link to thisIt is not enough to feed this huge population. The standard of living of all these people will eventually reach levels similar to those currently observed in the developped world. A competition for (scarce) resources will follow. This may lead to confrontations, possibly a new world war. Efforts should therefore be made to increase educational levels and teach family planning to curb the increase as quickly as possible.
Link to thisStudy of neandertal habitat may in the future dilute such a tentative hypothesis. Their migrations may well have to do with pursuit of familiar game as the weather fluctuates between cold and warm periods.
Very small differences in reproductive levels can doom competing species, as the authors surely know. Some interbreeding has been shown to have occurred, as well as some imitation or learning of sapiens technology by neanderthalensis.
Concerning the other theme: there is some indication that populations of sapiens may have passed a threshhold of overbloom already, and the present worldwide saturation may not hold for more than a couple more generations.
Link to thisMy comments are often far too long, so I leave you to research this and decide which present indicators or this peak are valid.
Developed countries like Netherland are close for the citizenship at last years for differnet countires. But with law level of population in those countries cause to allow provision to the different nations enter in to the Netherlands.
Link to this@ Fishin_tchr I do not dispute but one premise you based your argument upon. Obesity in the West is not due to OVER nutrition but rather to BAD nutrition. Processed foods which include grains and carbohydrates (corn additives, fructose, sugar, starches, flour, dextrin, dextrose, cane sugar, maltin, and endless others) are the reason for obesity. Humans evolved as hunter gatherers (we think) and therefore the kinds of foods to which they had access are exactly the foods which would keep us healthy (meats, fats, fruits and vegetable/legume/tuber plants) lean and old. Obesity does not stem from simply eating too much, but rather from complex interactions of our physiology with the ‘bad’ foods foisted upon us by industry, urbanization and capitalist driven, corporate controlled governments. It is likely true that obese individuals eat more than lean individuals but that is currently thought (by most) to be a result of the kinds of foods eaten, than the primary event.
Link to thisYes, we must call it BAD nutrition indeed, if 2 billion of us are either over- or underfed! We are too clever by half, having abandoned our species-specific, plant-based nutrition, in favour of virtual-reality food, such as, sugary , greasy, and/or salty concoctions passing as real food, just because our simplistic chimp’s brain registers the colourful images on the ad billboard or carton as REAL!
Even in paradise, like here in Bali, they serve synthetics in our hotel, like the neon-green juice
that passes under the name of ‘pineapple’,nicely spiced up with the help of mimicry coal-tar coloring and flavoring!
Our economy would have an even bigger decline, though, if everybody suddenly ate real food, as our gross domestic product is based on addictive,denatured,ridiculously condensed food, with sugar/caffeine- baits like Coke, and salt-laced Burgers to boot.
but if WE stop serving the holy cows of commercial food , in favor of naturally crunchy & spicy plant food and yummy curries, we all can live more happily and healthily thereafter. It’s easy as, like going for real Coconut instead of Coke. youthevity.com
Youthevity.com
Link to this