Above: Image © pagadesign, iStockphoto

I love a good sci-fi story! Especially when it’s about the future of our species. Have you ever wondered what will become of humans?

Evolution by natural selection

Like all living things, humans are the result of evolution by natural selection. Living things share the same natural world and often compete with each other in the struggle to survive and reproduce. Some win, some lose. Those that win pass down their genes to the next generation. Over thousands of years, as beneficial genes accumulate in its gene pool, a species adapts to its environment.

But our species’ capacity to adapt is unlike any other. The tools and technologies humans invent have had a powerful effect on our environment and on how we have evolved. For example, the discovery of fire and cooking were major evolutionary milestones. Cooked meals gave early humans access to food energy that would have otherwise been left unused. And this surplus energy helped fuel the development of the human brain.

Did you know? Our species—Homo sapiens—first appeared in Africa about 200,000 years ago. But we are related to earlier human species that lived millions of years ago.

More recent inventions, like antibiotics and vaccines, have forced the microbes that live all around us (and in us!) to evolve. And since we live in symbiosis with these microbes, they cause our bodies to evolve, too. It almost seems as if “playing god” is part of human nature. But how will new technologies affect human evolution in the future?

Reaching reproductive age

Up until the Industrial Revolution, which began around 1760, there were often severe restrictions on people’s life expectancy. Limited access to food and shelter, as well as widespread infectious disease, meant that significant numbers of people never reached reproductive age.

Today, life expectancy still varies greatly around the world. But many modern humans don’t struggle with the same basic needs anymore, or at least not in the same way. Thanks to better living conditions and advances in public health, humans live, on average, longer and healthier lives than they used to. As a result, they have a much better chance to reproduce and raise a family.

Complex technologies and killer microbes

Human life is also becoming increasingly dependent on ever more complex technologies. Ironically, adapting to the fast rate of technological change is one of our biggest challenges.

In nature, when the pace of change is too fast and there is no time to adapt, species can go extinct. But in this case, the pressure comes from us. If technology replaces biology as driving force of human evolution, will natural laws still apply? It’s hard to tell. But there are some things that are sure to impact the future of our species.

One of them is the sheer size of the human population: there are over 7 billion of us—and counting! And thanks to new transportation technologies, modern humans can move around the planet fairly easily. Together, these two factors mean a large gene pool and extensive crossbreeding.

Some scientists think it’s unlikely that our species will change much. Something very drastic would need to happen to push the human biology over the edge. It would take a disaster to kill a lot of humans quickly, or a big change in living conditions to select for significantly different traits.

This brings up another important player: the microbe. Deadly infectious diseases caused by new viruses could decimate humans. They could also change the future of the species. Viruses and other microbes are the most abundant and versatile creatures on the planet. Their ability to multiply and adapt is the best.

Genetic engineering and intelligent machines

But let’s assume technology like vaccines and antibiotics will help humans stay one step ahead of deadly microbes. What else could affect our future as a species? Many researchers predict it will be assisted reproduction and genetic engineering.

In vitro fertilization (IVF) and freezing eggs and sperm for later use has opened new possibilities for reproduction. With the advent of “test-tube babies” in the 1970s, humans overcame many natural limitations on fertility, timing of conception, and family size. Embryos can be made using egg or sperm from donors. They can also be screened for disorders and carried by a surrogate instead of the natural mother.

Soon it may even be possible to modify an embryo’s genes before implantation. This would help to prevent disease and fix defects. But since people don’t all agree on what constitutes a defect, it also raises big ethical questions.

Enhancing human intelligence, as well as other traits, may prove hard to resist. Will we become the designers of our own evolution? Will humans evolve themselves into a species of supermen? The closer we get to this possibility, the more intense the debate will get. The challenge for us a society and a global community is to find a safe and fair way forward.

Did you know? The term “artificial intelligence” (AI) was coined by the computer scientist John McCarthy in 1956. The goal of AI is to create intelligent machines.

But what if we have to compete with robots? Intelligent machines, even ones that can learn and adapt, exist already. And they are getting better than humans at many things, including chess! Will humans stay in control? Maybe our descendants will learn to collaborate with robots. Or will the emergence of rogue robots become inevitable? From Star Trek to Doctor Who, science fiction has provided plenty of examples of both friendly and killer robots.

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At this point, the future of the human species seems wide open. What’s the best that could happen? What’s the worst?

Learn more!

News and magazine articles on how tools and technology have shaped human evolution:

From Homo sapiens to Homo technologicus (2015)
Mindy Perkins, The Stanford Daily

Why fire makes us human (2013)
Jerry Adler, Smithsonian Magazine

Sorry, vegans: Eating meat and cooking food made us humans (2012)
Christopher Wanjek, NBC News Science

News articles, magazine articles, and commentaries on the future of human evolution:

Chinese scientists genetically modify human embryos (2015)
D. Cyranoski & S. Reardon, Nature

Humans could be in the middle of a huge evolutionary transition (2014)
Christina Sterbenz, Business Insider

Where is human evolution taking us? (2014)
Scientific American

Unnatural selection: Is evolving reproductive technology ushering in a new age of eugenics? (2012)
Carolyn Abraham, The Globe and Mail

Future Humans: Four ways we may, or may not, evolve (2009)
James Owen, National Geographic News

Magdalena Pop

Magda Popp

I am a biochemist and educator working to increase students’ motivation for learning science. I earned my PhD at the Max Planck Institute for Biophysical Chemistry in Göttingen (Germany), where I did research on human viral infections, primarily HIV/AIDS. In 2001 I started teaching high-school science in Canada, and in 2013 I became a mentor for Alberta's high school teams participating in the international Genetically Engineered Machines (iGEM) competition. Writing articles for CurioCity is one of the ways in which I follow my passion for sparking genuine excitement and curiosity about science. Check out my blog - School Sense - here.


En tant que biochimiste et éducatrice, je travaille afin de susciter l’intérêt des élèves pour les sciences. J’ai obtenu mon doctorat de l’Institut Max Planck de chimie biophysique à Göttingen, en Allemagne. C’est là que j’ai fait des recherches sur les infections virales humaines, principalement le VIH/SIDA. En 2001, j’ai commencé à enseigner les sciences aux élèves du secondaire au Canada. En 2013, j’ai été un mentor pour les équipes albertaines participant à l’iGEM, une compétition internationale de machines génétiquement modifiées. La rédaction d’articles pour CurioCité est une des façons dont j’essaie de susciter un véritable enthousiasme pour les sciences. On peut visiter mon blogue, « School Sense », en cliquant ici.



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