Scientists Say We Once Shared the Planet With at Least 8 Other Human Species — And Now We’re the Only Ones Left

Did you know that a long time ago, at one point, modern humans were not the only human species walking around the planet? Scientists have estimated that there are at least 8 other human species living on Earth at the same time we did.

They all lived across Africa, Europe, and Asia with varying sizes and body types. Homo Sapiens, the modern humans, are actually not the strongest nor the biggest, but we are now the only surviving hominin. Let’s find out who these other human species are and why we are the only ones left.

A Planet Packed With Diverse Humans

Home Sapiens evolved about 300,000 years ago, but during that time, at least eight other human species were walking the Earth alongside us and other animals. These close relatives included Neanderthals, Denisovans, Homo erectus, Homo floresiensis, Homo naledi, Homo rudolfensis, Homo heidelbergensis, and Homo antecessor.

Just like we did back then, they lived in parts of Africa as almost everyone was theorized to have originated from this land, or at least the modern humans did, then they migrated to Europe and Asia. However, there are actually fewer and limited fossil records observed from other species in Africa. Additionally, the other species like Homo heidelbergensis has more fossil evidence prevalent in Europe than Africa.

This does not contradict the out of Africa theory directly, rather it is more about the preservation of their fossils being harder as most other human species existed long before Homo Sapiens.

Read more: Big Think

We Met, and Sometimes Mated

Why Are We The Only Humans Left?

Our evolutionary timeline and existence overlap with other human species for about tens of thousands of years. That means our ancestors shared landscapes, climate, and even some of their DNA with our relatives. Some evidence is also present stating that Neanderthal and Denisovan DNA shows that modern humans also interbred with them.

Scientists have also estimated that humans today outside of Africa can have 1 to 4% Neanderthal DNA. This means that they are not just neighbors, they actually have become a part of our long line of genetic tree. They leave their footprints in our very own genetic makeup, affecting our metabolism, immune systems, skin, hair, and sleeping patterns.

Why They Disappeared

Neanderthals are often cited to possess stronger physical strength compared to Homo Sapiens. However, they are extinct now, which highlights that it is not always the strongest that gets to survive, and that nature is much trickier than that.

So, what happened to them and our other cousins? Studies are still being conducted and no definitive answer is present but the leading theories suggest that they might have been absorbed into Homo sapiens through breeding.

We still do not know the complete story; it could also be because of climate shifts and the presence of competition. Us being more witty and smarter could also play a role, maybe outlasting them in this game of survival. Either way, the thing we know is that by about 40,000 years ago, we were the only human species left.

Read more: The Guardian

What It Means for Us Today

This ancient diversity reminds us that we got here because our ancestors adapted and survived, even with the presence of other human species as competitors. This will help us reshape our understanding of what it means to be a human.

Because of our culture, tradition, intelligence, and desire to survive were traits not only unique to us but also across many kinds of humans. Our legacy as modern humans is a reflection of the many different kinds of paths and timelines that merged and converged into who we are today.

We're the Last Humans Left

Author's Final Thoughts

We once lived on a planet that contained many other different kinds of humans, and this diversity might have helped us more than we ever realized. The fact that we also share DNA with some of them means our lineage has come with a lot of influences. Today, only modern humans are the surviving species, but our history includes many now-extinct relatives and their stories with it.

Read more: Genetic Analysis Confirms That Blue Eyes Came First Before Light Skin

References & Further Reading

Détroit, F., et al. (2019). A new species of Homo from the Late Pleistocene of the Philippines. Nature. https://doi.org/10.1038/s41586-019-1067-9

Brown, P., et al. (2004). A new small-bodied hominin from the Late Pleistocene of Flores, Indonesia. Nature. https://doi.org/10.1038/nature02999

Berger, L. R., et al. (2015). Homo naledi, a new species of the genus Homo from the Dinaledi Chamber, South Africa. eLife. https://doi.org/10.7554/eLife.09560

Reich, D., et al. (2010). Genetic history of an archaic hominin group from Denisova Cave in Siberia. Nature. https://doi.org/10.1038/nature09710

Rizal, Y., et al. (2020). Last appearance of Homo erectus at Ngandong, Java, 117,000–108,000 years ago. Nature. https://doi.org/10.1038/s41586-019-1863-2