Do you know how many we are on planet earth at the moment? Over 7.7 billion and the number tends to increase at the rate of about 75 thousand human beings every day, as a balance between newborn and dead.

World population, a race that does not stop

As if to say that by the end of the year there will be 82 million mouths to feed more than there were at the last New Year. The two most populated countries in the world are China (over 1.43 billion according to the latest estimates) and India (climbed above 1.36 billion).

More detached are the following: the United States (over 329 million inhabitants), Indonesia (almost 271 million), Pakistan (213 million) and Brazil (211 million).

Comparing the trend of the world population in history, from the birth of agriculture, about 8 thousand years before the birth of Christ (when it is estimated that 5 million human beings lived on earth) up to 1,800 AD, when the world population has reached one billion, growth has been imperceptible.

But already in 1930, the figure had already doubled, while the third billion was reached in 1960, the fourth in 1974, the fifth in 1987, the sixth in 1999 and the seventh in 2011. Now, fortunately, the growth is slowing down and if in 1970 there was about half of the current population, now it would take another 200 years for it to double again if it ever happens.

Water and land prevent a further doubling of the world's population

According to Harvard University sociobiologist, Edward Wilson, in fact, we will not reach the last doubling because of a series of limits. In addition to the limited availability of drinking water, it must be considered that even the land destined for the cultivation of foodstuffs is limited.

Even if we all became vegetarians and therefore consumed entirely agricultural crops, rather than turning them partly into animal feed, today there are no more than 1.4 billion hectares of arable land in the world, which could produce at most 2 billion tons of wheat per year.

Enough to feed 10 billion vegetarians or 2.5 billion omnivores following an "American diet". Other scientists like the biologist Joel Cohen of Columbia University report further limits such as the atmospheric concentration of coal, the nitrogen cycle or the available amount of phosphorus.

So if the 8 billion could already be reached 2023, only between 2037 and 2057 we should touch respectively 9 and 10 billion of living human beings, then the race of the human race could have almost reached the end of the line.

To grow again you will have to look at space

Unless you can get started large-scale colonization of space (in 2030 the United States would like to send a first human expedition to Mars) or, more concretely, that the birth rate falls, as in part is already happening.

Germany, for example, has stopped growing for a decade , Italy only grows through immigration ( and despite the rhetoric of some populist parties starting from 2025 this too should start to decline ), while China will begin to decline from 2035 .

By that date, China will have been overtaken by India which, although slowing down, will continue to grow at least until 2050, when over 1.6 billion Indians will exist on the planet.