What Would Happen to Humanity’s Survival If We Stopped Having Children?

[Un article de The Conversation écrit par Michael A. Little – Professeur émérite distingué d”anthropologie, Université de Binghamton, Université d’État de New York]

Very few people live beyond a century. Thus, if no one had any children, there would probably no longer remain humans on earth in 100 years. But before that, the population would begin to decrease, as the elderly die without any new birth coming to replace them. Even if all births suddenly ceased, this decline would initially be progressive.

A collapse of societies

But little by little, there would no longer be enough young people to ensure essential tasks, which would cause a rapid collapse of societies around the world. Some of these upheavals would undermine our ability to produce food, provide health care and accomplish everything on our daily lives. Food would be rare, even if there were fewer mouths to feed.

As a teacher of anthropology who devoted my career to the study of human behavior, biology and cultures, I readily recognize that this scenario would have nothing delighted. Ultimately, civilization would collapse. It is likely that there would be no longer many people within 70 or 80 years, rather than 100, due to the shortage of food, drinking water, drugs and everything that is easily accessible and essential to survival today.

The trigger: a global disaster

It must be recognized that a brutal stop of births is highly improbable, except in the case of a global disaster. A possible scenario, explored by the writer Kurt Vonnegut in his novel Galápagoswould be that of a highly contagious disease making infertile all people of childbearing age.

Another scenario: a nuclear war that no one would come out alive – a theme treated in many frightening films and books. Many of these science fiction works stage travel in space. Others try to imagine a less fanciful future, where reproduction becomes difficult, resulting in collective despair and loss of freedom for those still capable of having children.

Two of my favorite books on this theme are The scarlet servant From the Canadian author Margaret Atwood, and the sons of the man of the British writer PD James. These are dystopian stories marked by human suffering and disorder. Both were adapted in television series or films.

In the 1960s and 1970s, many worried about global overpopulation, synonymous with other types of disasters. These fears have also fed many dystopian works, in the cinema as in literature.

An example: the American series “The Last Man On Earth”, a postapocalyptic comedy that imagines what could happen after a deadly virus has decimated most of humanity.

%iframe_0%

On the way to 10 billion inhabitants

The world's population resolutely continues to grow, even if the pace of this growth has slowed down. Experts who study demographic dynamics believe that the total number of inhabitants will reach a 10 billion peak in the 2080s, compared to 8 billion today and 4 billion in 1974.

The United States population is currently 342 million, around 200 million more than at the time of my birth in the 1930s. It is a large population, but these figures could gradually decrease, in the United States as elsewhere, if the number of deaths exceeds that of births.

In 2024, around 3.6 million babies were born in the United States, against 4.1 million in 2004. At the same time, around 3.3 million people died in 2022, compared to 2.4 million twenty years earlier.

As these trends evolve, one of the essential issues will be to maintain a viable balance between young people and the elderly. Indeed, it is often young people who run society: they implement new ideas and produce the goods on which we depend.

In addition, many elderly people need help for everyday gestures, such as preparing to eat or dressing. And a large number of jobs remain more suitable for under 65 than those who have reached the usual retirement age (later in the United States).

%iframe_1%

Down birth rate

In many countries, women today have fewer children during their fertile life than in the past. This drop is particularly marked in some countries such as India or South Korea.

The decline in births observed currently is largely explained by the choice of many people to have no children, or to have less than their parents. This type of demographic decline can remain manageable thanks to immigration from other countries, but cultural and political concerns often slow down this solution.

At the same time, more and more men encounter fertility problems, which makes their ability to have more uncertain children. If this trend worsens, it could strongly accelerate the decline of the population.

%iframe_2%

The disappearance of Neanderthals

Our species, Homo Sapiens, has existed for at least 200,000 years. It is a very long period, but like all living beings on earth, we are exposed to the risk of extinction.

Take the example of Neanderthals, close relatives of Homo Sapiens. They appeared at least 400,000 years ago. Our modern human ancestors cohabited a time with them, but the Neanderthals gradually declined until disappearing about 40,000 years ago.

Some research suggests that modern humans have been more effective than Neanderthals to ensure their subsistence and reproduce. Homo sapiens would have had more children, which favored its survival.

If our species were to disappear, this could open the way to other animals to prosper on earth. But it would also be a huge loss, because all the richness of human achievements – in the arts, sciences, culture – would be destroyed.

In my opinion, we must take certain measures to ensure our future on this planet. This involves the fight against climate change, the prevention of armed conflicts, but also through an awareness of the importance of preserving the diversity of animal and plant species, which is essential to the balance of life on earth, including for our own survival.