What do we do with 10 billion people?
Apparently we are going to add three billion people to the global population by the end of this century. Given the fact that the world just hit 7 billion people, it will mean providing for 10 billion by the year 2100 and still growing. The first billion took from the beginning of man to the 1800's. A second billion took 120 years, Two more billion in 55 years by 1975. Six in 23 years by 1998 and now seven after 13 more years in 2011. Can we do it? Can the world feed, house, and care for all these people? The answer is a qualified yes.
The question centers on the availability of resources. In the early 1800s, Thomas Robert Malthus suggested that population increase is limited by the means of subsistence. It hasn't worked so far, largely because of scientific advances in agricultureand mechanization that have opened new areas for farming andmassively increased the productivity of our farmers.
We humans seem to be able to survive on ever decreasing plots of land while making them ever more productive. From 1950 to 2000 in the US the average amount of milk produced per cow increased from 5,314 pounds to 18,201 pounds per year (+242%), the average yield of corn rose from 39 bushels to 153 bushels per acre (+292%), and each farmer in 2000 produced on average 12 times as much farm output per hour worked as a farmer did in 1950.(http://www.ers.usda.gov/publications/EB9/eb9.pdf) Presumably that performance can be replicated in other parts of the world.
As the yields have increased the need for labor has decreased. The US farm population is less that 3 million and it sustains a food industry employing more than 20 million. But the number of farms is declining. A new generation of computer driven robots will soon replace many of today's farm workers. Robots with artificial intelligence are being developed to plough and seed fields, and feed cows.
The Israelis are working on a robotic mellon picker that can tell if the mellon is ripe. "Watermelon is grown in 90 countries with worldwide production exceeding 50 billion pounds per year. The United States is the world's fourth largest producer. According to the Department of Agriculture 70% of American households buy watermelon. The essential 'robotic' blending of intelligent sensing with mechanical actuation can be found in vision-guided tractors, product grading systems, planters and harvesters, applicators for fertilizers and pest control. Robot manipulators can divide plant material for micropropagation in sterile conditions; others can skin fruit for canning." http://ishitech.co.il/0903ar3.htm
Robots with artificial intelligence are being developed to plough and seed fields, and feed cows. Indoor production of plants is increasing and gene splicing is allowing researchers to produce commercial volumes of vanilla in labs eliminating the soil the cultivation, the harvest and the farmer (http://www.converge.org.nz/pirm/nutech.htm) A fully automated farm is likely possible in the next 25 years.
There will no doubt be problems as we try to accommodate to a more crowded world. Technology, invention, investment and equitable distribution can solve most of them. The problem does not depend so much on numbers of babies born as it does on their productivity. And productivity has been steadily increasing for over a century (source). If you use the output of the average worker in 1950 working a 40 hour week as your base, average worker today would need only 11 hours to produce the same quantity and at a much higher level of quality.
Much of the world is facing unemployment and underemployment even in areas enjoying 9% growth per year. China has been growing at 10.3% and yet in 2009 still had 4.3% unemployment. Egypt, before the revolution was growing at 5.1% with an unemployment rate of 9.7%. And these figures do not include the underemployed. Think about the future of clerical workers, for example, in the US. In 2004 there were 31 million general office clerks, 1.5 milliion office administrative supervisors and 4.1 million secretaries. Their salaries ranged from $23,000 to $41,030. And many have been replaced by machines. But how many secretaries are left? And how many will be left in 10 more years?
Retail sales personnel numbered about 4.5 million jobs. Medium hourly wage was $9.89in 2008. But as companies look for ways to maximize profits, they also look for ways to reduce their most expensive input - labor with its increasingly expensive benefits. The manufacturing and service sectors are continuously embracing new technology that can replace people at a lower price. Even old technology is stunning in its efficiency. "A human teller can handle up to 200 transactions a day, works 30 hours a week, gets a salary anywhere from $8,000 to $20,000 a year plus fringe benefits, gets coffee breaks, a vacation and sick time... In contrast, an automated teller can handle 2,000 transactions a day, works 168 hours a week, costs about $22,000 a year to run, and doesn't take coffee breaks or vacations" (source). Nor does it need health insurance.
It is easy to visualize a world in the not so distant future, where many jobs and entire sectors of employment will be replaced by more efficient, reliable and cheaper machines and artificial intelligence. So what are we going to do with the redundant people? The greatest problem we may face in the future is not what we need to do to accommodate the basic needs of more people, but how we keep them productively occupied. Work has been our means of keeping score, whether it is by virtue of income or status or both. If we do not have productive work, how in today's terms, do we validate our lives. There are just so many holes of golf that a person can play. This is the most challenging problem of the next half century.