The Last Human Standing: What If We Still Shared the Earth with Other Humans?
We tend to place quite a wide gap between us Homo sapiens and the rest of the animals. Alone in our complexity, culture, inventions, and contemplation. However, we were not always alone, we are merely the last humans to survive.
For most of our history, other human species lived alongside us— primarily Neanderthals and Denisovans, as well as Homo floresiensis, Home naledi, and possibly other branches of humanity. I can’t help but feel a sense of loneliness and sadness for the shared human experience that could have been.
https://theconversation.com/our-homo-sapiens-ancestors-shared-the-world-with-neanderthals-denisovans-and-other-types-of-humans-whose-dna-lives-on-in-our-genes-191913
I also wonder if our hopeful search for intelligent extraterrestrial life partially stems from this isolating feeling of being the single “conscious” (let’s not have that discussion here) species on the planet.
Neanderthals and Denisovans were not mere “cavemen”, but sophisticated beings with their own tools, art, and social structures. The fact that Homo sapiens are the only human species to have survived to the present day is a remarkable and perplexing outcome. What if it had turned out differently? What if Neanderthals and Denisovans had survived, or if other human species had evolved in parallel with us? What would the world look like today, and how would our understanding of humanity change?
“If any of these species had survived into contemporary times, we would be faced with an ethical question which is novel: negotiating our stance toward a species that is not quite human, but too close to be regarded as simply animal…” - Professor Neil Levy, Professor in Philosophy at Macquarie University.
https://blog.practicalethics.ox.ac.uk/2015/10/living-with-other-hominids/
Neanderthals: Our Closest Relatives
The Neanderthals, the closest relatives of Homo sapiens, lived in Europe and parts of Asia for around 300,000 years before mysteriously disappearing about 40,000 years ago. Often depicted as brutish, Neanderthals were in fact highly intelligent and resourceful. They developed tools, controlled fire, and made clothing and jewellery, suggesting a genuinely complex culture. Recent studies even suggest that Neanderthals had a rudimentary form of language, art, and spiritual beliefs.
Neanderthals were physically stronger than Homo sapiens, with larger brains and adaptations to cold environments. However, they were also capable of modifying their environment, using tools to hunt large animals and processing plants for medicinal purposes. Their extinction remains a topic of intense debate. Was it due to competition with Homo sapiens, disease, or environmental changes? Or did the Neanderthals assimilate into Homo sapiens populations through interbreeding? Genetic evidence shows that many non-African humans today carry traces of Neanderthal DNA, a genetic signature of our intermingling.
Denisovans: The Mysterious Humans of the East
Less known but equally significant are the Denisovans, an ancient human species identified through DNA extracted from a finger bone and teeth found in the Denisova Cave in Siberia. Unlike Neanderthals, we have very little fossil evidence of Denisovans, making them one of the most enigmatic human species. They lived in Asia and interbred with both Neanderthals and Homo sapiens, leaving genetic legacies in modern humans—especially in populations in Southeast Asia and Oceania.
Denisovans, like Neanderthals, were well-adapted to their environments. Genetic evidence suggests that they may have been uniquely adapted to living at high altitudes, with some populations possibly contributing to the gene pool of modern Tibetans, who have genetic adaptations to thrive in low-oxygen environments.
If Neanderthals and Denisovans had survived, what would our relationship have been like? Would we have regarded them as equals, or would they have been relegated to the role of "the other"? Would we have formed communities, or would competition for resources have driven us apart? These questions challenge us to reconsider how we view other cultures, and perhaps how we might have treated these closest of relatives.
Interbreeding: The Blurred Lines of Humanity
One of the most intriguing aspects of human evolution is the evidence of interbreeding between Homo sapiens, Neanderthals, and Denisovans. Through genomic studies, scientists have discovered that all non-African humans carry small amounts of Neanderthal DNA, and in some populations, traces of Denisovan DNA as well. This suggests that, far from being an entirely separate species, Neanderthals and Denisovans were part of a complex web of human evolution.
The process of interbreeding would have blurred the lines between species, challenging the traditional notion of what it means to be a separate species. If we had lived alongside Neanderthals and Denisovans, it is likely that our relationships with them would not have been simple. Would we have embraced these “others” as equals, or would we have viewed them as inferior beings, much as societies have done with those perceived as different throughout history?
The Fragility of "Us"
Homo sapiens have come to see ourselves as the pinnacle of evolution. We’ve mapped the stars, unlocked the secrets of DNA, and even turned our own creations—artificial intelligence—into something that might one day surpass us. We have evolved not just biologically, but culturally, creating systems of belief, governance, and law that bind us together. Yet, it is critical to remember that we are not the only humans to have walked this Earth. Once, there were other branches of humanity—others who might have been our equals or even our superiors in ways we can only speculate about.
Consider, then, how fragile our ascendancy truly is. The Neanderthals, for instance, were no lesser beings. Their brains were, in some cases, larger than ours, and they lived in harsh, ice-age conditions, mastering the challenges of their environment with tools and techniques that remain remarkable, even by today's standards. Had they survived—had they learned to live alongside us developing their own languages, arts, and technologies —what might they have contributed to our shared history?
The Lurking Fear of "Otherness"
In the absence of Neanderthals and Denisovans, we have become accustomed to the idea that we are the only intelligent species, the only humans on Earth. But what happens when we face the reality of having to share the world with others who are like us, but not quite like us? There is an existential question here: how do we reconcile the existence of another human species with the foundational belief in our own exceptionalism?
Our relationship with the “other” has always been fraught with tension, from the fear of the stranger in ancient times to the division between races, nations, ideologies, and sports teams today. But the presence of another species, closely related to us in evolutionary terms, would amplify these tensions to an unimaginable degree. How would we respond to their differences? Would we, in the end, do what we always do—look for ways to separate, to elevate ourselves above them? Or would we find a way to unite, to forge a common bond out of the shared understanding of what it means to be human?
On an Earth where Neanderthals or Denisovans survived, we would have faced an unprecedented moral dilemma: could we justify subjugating or driving out another species that was, in many ways, our equal? And if we didn’t, if we lived side by side, could we have created a society with mutual respect, empathy, and cooperation? Would we have learned to embrace difference in ways we have not yet fully achieved, or would the same historical forces of division, fear, and competition have dominated?
What Does It Mean to Share the World?
Let’s entertain a thought: what if we weren’t the only ones who had the ability to ponder such questions? What if the Neanderthals, with their powerful bodies and complex brains, also spent their nights gazing at the stars, wondering about their place in the universe? Could their philosophies have mirrored ours, touching on the same existential questions that we ask today about the meaning of life, the nature of suffering, and the pursuit of happiness?
The very existence of another human species forces us to confront our own assumptions. If we had shared the Earth with other humans, our societies might have been shaped by a far more nuanced understanding of what it means to be human. Perhaps the constant presence of "the other" would have pushed us to refine our empathy, to build more inclusive systems that recognised the inherent value of all human beings. Perhaps the interplay between Neanderthal and Homo sapiens, for example, would have led to a richer, more diverse cultural heritage, where arts, language, and technology were constantly evolving in dialogue.
Alternatively, it’s possible that the pressure of coexisting with another intelligent species could have pushed us into a darker, more competitive path—one driven by the primal fear of losing our place in the world. What would it have meant for us, as a species, to share a planet with others who could just as easily have been our competitors as our companions?
There is something haunting about the thought that, at some point in the not-so-distant past, we were just one of several species of humans. In another timeline, Homo sapiens might not have been the survivors at all. Neanderthals, with their close-knit communities and incredible survival skills, might have outlasted us. Or perhaps Denisovans, whose genetic contributions still live on in us today, might have led humanity into a new era.
A Counterfactual Thought Experiment: A World Shared by Humans
What would a world shared by humans—plural—look like today?
1. The Geography of Humanity
In our current timeline, the Earth’s geography has been carved out by a history of colonialism, imperialism, and modern political struggles. Borders are often defined by the legacies of conflict and conquest. But in a world where different human species coexisted, would those borders even look the same?
Would Neanderthals have developed their own territories, perhaps in the harshest, least hospitable environments that Homo sapiens could not dominate? In contrast, would Homo sapiens have focused on areas with more temperate climates, more suited to agriculture and dense population centres? The Denisovans, with their adaptations to high altitudes and cold environments, might have claimed the mountains and plateaus, from the Tibetan Plateau to the Andes. The survival of multiple species would likely have led to a complex network of territories—each species with its own ecological niche, but also with the inevitable overlap and competition for resources.
The maps of the world would be a patchwork of different territories—borders drawn not only by political power but also by ecological necessity and cultural divisions. What would the relationship be like between, say, a Neanderthal-majority population in the European highlands and Homo sapiens living along the Mediterranean coasts? Would these regions have developed entirely different cultural identities, languages, and ways of life?
2. Social Structures and Governance
Governance in such a world would be radically different. In a purely Homo sapiens world, we have come to accept the idea of nation-states—autonomous political units often defined by the lines on a map. In this counterfactual world, however, the existence of multiple human species would have likely complicated that model of governance.
In some regions, the coexistence of multiple human species might have fostered cooperation and cohabitation. Perhaps shared councils or federations of human groups would have formed, where each species had its own voice and influence. These governing bodies could have become a reflection of the diversity of the human experience—at times cooperative, at others conflict-ridden, depending on the capacity for empathy and respect.
Would tensions between Homo sapiens and Neanderthals have led to the creation of segregated nation-states? In our world, division and separation often occur along ethnic or racial lines, but in this scenario, the very existence of different human species could have meant that political entities were defined by biological and cultural differences. Would certain species have been relegated to subjugation, much as indigenous peoples have historically been treated in our own world? Or would political systems have been structured around the idea of equality, fostering a shared humanity that transcended species boundaries?
The potential for cultural and political alliances or deep divisions between species would have reshaped the development of global governance. Perhaps the United Nations would not be a human-centric body at all, but a broader federation representing all human species—each with its own distinct needs and rights. If we were to share the Earth with other humans, could we create a world where all species had equal rights, representation, and opportunities?
3. Relationships and Reproduction
One of the most fascinating—and perhaps uncomfortable—questions raised by the idea of multiple human species is how relationships between them would work. In our world, intergroup relations have always been complex. The divide between different ethnicities, races, and cultural groups often leads to tension, but also to fusion and integration. But how would that play out if Homo sapiens were not the only humans?
Would romantic relationships, marriages, or even families be common between the species? The genetic legacy we see in modern humans—our Neanderthal DNA—suggests that, at some point, interbreeding did occur. Would interbreeding have become commonplace, or would it be discouraged, even taboo? Would societies frown upon such unions, creating divisions that echoed the divisions between nations or ethnic groups in our own world?
Alternatively, it’s possible that human species would find common ground through interbreeding, leading to a population where genetic diversity expanded beyond the already broad scope of Homo sapiens. What would it mean to grow up in a family with Neanderthal parents, or to have a child born of a mixed-species union?
4. The Cultural Fabric: Art, Language, and Technology
The presence of multiple human species would have dramatically influenced the cultural development of the planet. Imagine the explosion of languages that might have arisen—Neanderthal languages, Denisovan dialects, and Homo sapiens’ own rich tapestry of languages. How might languages from these species have influenced one another? Could Neanderthal art, with its heavy use of symbolism, have influenced the earliest Homo sapiens cave paintings? Would Denisovan architecture, which we can only speculate about, have given rise to new ways of building and living?
Competition and cooperation between species may have led to even more fascinating developments. It’s possible that Neanderthals, with their well-developed tools, could have developed their own unique technological innovations—perhaps focusing on materials we never thought to use or processes we overlooked. Would their tools and systems have merged with Homo sapiens’ more elaborate technologies, leading to an entirely different technological revolution? What would a world look like where multiple intelligent species constantly exchanged ideas, refined methods, and created hybrid technologies?
In this speculative world, our approach to science, philosophy, and art would have been much more pluralistic. The dialogue between species—each with its own ways of thinking, creating, and problem-solving—could have led to an intellectual renaissance, or it could have sparked fierce conflict over whose knowledge systems were the “correct” ones.
Human Family Reunion: De-extinction of Our Lost Cousins.
The possibility of resurrecting extinct human species’ is not just a scientific frontier—it’s a gateway to curious philosophical questions. Companies like Colossal are already working to resurrect animals like the Woolly Mammoth and the Thylacine, proving that the seemingly impossible is within reach. Their work with de-extinction, using advanced genetic technology to reawaken these species, demonstrates that with the right scientific breakthroughs, we could one day bring back humans who have been lost to time.
https://colossal.com/
If we revive the Neanderthal, what does it say about who we are today? Could these ancient beings share our world, our societies, and our culture, or would they forever remain out of place, now trapped in a future that doesn’t belong to them?
Could we look at the resurrected Neanderthal and see a reflection of ourselves in their eyes, or would their “otherness” remind us that there are limits to our shared human identities?
This raises another troubling question: Are we creating life to explore a future, or are we simply resurrecting the past, unable to let go of what we have lost? And when we bring these beings into existence, how will we treat them? Will we grant them the same rights, the same dignity as ourselves, or will they remain experiments in a biological museum, mere curiosities for us to study and control?
Would these resurrected humans remind us of the fragility of life? Could their presence challenge our deepest assumptions about the superiority of modern humans, forcing us to confront the possibility that there were once other ways of being that were just as valid, just as alive, as our own?
Bringing back a species that once walked the Earth before us would be a testament to humanity’s desire to conquer death—to rewrite the end of the story of life itself. But it also carries with it a profound sense of responsibility: the duty to care for those we resurrect, to ensure their survival, and to accept them as part of the same tapestry of human existence we have fought so hard to preserve.
Share your thoughts
1. If we had continued living with other Humans, would we have mostly been competitors, or collaborators?
2. How would recorded history have been different with multiple Human species interacting?
3. Would you like to see extinct Human species brought back?
