More modern guesses are hardly more scientific, ranging from one billion to one trillion. Norton, As it is, the world produces enough food to feed everyone alive today—and more. Globally, farms produce enough calories to support a population of roughly 11 billion people fed 2, calories per day.
That's because human ingenuity—such as the modern breeding of staple crops, such as wheat, for higher yields, known as the Green Revolution—has outpaced, so far, environmental limits. Yet, there are still more than a billion hungry people on the planet today.
Twelve years later one of the 78 million children born this year is the seven billionth person. It may take 14 years to reach eight billion and it may take even longer to reach nine billion. But we're still not past "peak people," which could top out at After all, in the s, U. As it stands, the people of the planet seem to be leaning toward a peak in population followed by a gradual decline—a 21st-century world of the aged, which can be seen today in Japan or parts of Europe—but there is still a good chance of continued growth in our numbers.
The U. If the choices we make are a little different, there could be as many as 16 billion of us by the end of this century—and that number may prove more than the planet can bear if our lifestyles don't keep pace with our numbers.
David Biello is a contributing editor at Scientific American. Follow David Biello on Twitter. Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue. See Subscription Options. Go Paperless with Digital. Read more from this special report: 7 Billion People and Counting. Norton, As it is, the world produces enough food to feed everyone alive today—and more.
What's that, U. Census Bureau? The 7 billionth baby won't be born until April? What the heck is going on here? Will the real 7 billionth baby please stand up? Or at least give us a little baby fist pump? Turns out no one has any freaking idea who the 7 billionth human on the planet is. The celebrations in the Philippines and India today are merely symbolic—demographers don't know who actually deserves the crown. The 7 billionth human might have been born in August, or might still be in the womb.
The problem is that so many developing countries have poor demographic records. United Nations population estimates chief Gerhard Heilig says it's "nonsense" to imagine anyone could actually pinpoint who the 7 billionth baby because estimates come with a 1 to 2 percent margin of error. When you're talking about 7 billion that comes out to about 56 million people, and he says the birth in question could have happened six months ago or might be six months from now.
So the U. Also based on projections, the U. On or around Oct. Even more staggering is that of the 7 billion people on Earth, about 1. About Yes, population has risen very quickly over the last century.
Demographers do expect a decline in the population growth rate, but absolute numbers will continue to rise, likely hitting 9 billion by Meanwhile, we look back at history's past population milestones, asking: "How has the world changed? The world's first billion-person milestone was a long time coming. Estimates of historical populations can be rough, but the U. Census Bureau pegs the global population at a paltry 5 million people in B. Certainly, humans remained scarce until the development of agriculture some 10, years ago.
Even after our kind began farming, it was a slow climb to the million-person mark around B. From there, population growth gets a bit more exciting. Somewhere around A. By about , the population had doubled to between million and million. Plagues and wars took a toll on the global human population before the s, but the numbers then started a steady tick upward.
The birth year of the world's billionth baby will never be certain, but it's likely he or she came into the world around Beethoven was big that year, and already going deaf. Lewis and Clark made it to the Pacific Ocean. Napoleon was on a roll in Europe, 10 years from his defeat in the Battle of Waterloo. With the exception of a few coastal outposts, most of Africa was a complete mystery to Europeans.
In China, the Qing Dynasty had just put down the White Lotus Rebellion, a tax protest that ultimately killed about 16 million people — a reminder that mass death and population growth don't necessarily cancel one another out. It had taken thousands of years for the population to reach 1 billion, but 2 billion was barely more than a century away.
The 2 billionth baby was likely born in the late s, perhaps ; the U. This sudden takeoff of population makes sense in the context of a phenomenon called the demographic transition. In the transition, a population goes from one with high birth rates and high death rates imagine farming families having seven or eight kids in hopes of a few reaching adulthood to one with low birth rates and low death rates where parents usually have one or two kids and expect them to grow up.
In the midst of this transition is a period when death rates are declining but people have yet to alter their behavior: They still have lots of kids. Even if those kids decide to have only a few children of their own, population will remain high, because there are so many potential parents. The agricultural and industrial revolutions led to gradually declining death rates in the Western world starting in the s, while birth rates remained fairly high for generations.
As developed countries began to see falling birth rates, developing countries entered the transition period of declining death rates and high birth rates. Some countries in sub-Saharan Africa are just entering the demographic transition today.
But back to If the 2 billionth baby was indeed born in this year, he or she came into being the same year that the first trans-Atlantic telephone call was made from New York City to London.
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