How the human species has evolved and what the next human species will be by Don Simborg

By Guest Contributor Don Simborg

Author of The Fourth Great Transformation, Don Simborg, explains how the human species has evolved and what the next human species will be.

“If we could replay the game of life again and again . . . the vast majority of replays would never produce (on the finite scale of a planet’s lifetime) a creature with self-consciousness.”STEPHEN JAY GOULD, Full House

We, Homo sapiens, are the only human species left on Earth. For 98% of our time on the planet, though, other human species co-existed with us. Why have we survived while all the others have perished? And specifically, why did the Neanderthals, our closest relatives, go extinct? They had brains slightly larger than our own, used tools, had some type of language, created wall art, buried their dead and had their own culture. The debate still rages as to whether we outsmarted them somehow, with better tools and language, or perhaps we just outnumbered them over time, with our continual migrations out of Africa. The evidence is simply insufficient to reach a definitive conclusion.

You may then wonder how we can predict our future, if our ability to nail down the past is so difficult. There was no written documentation available 39,000 years ago, when the Neanderthals perished. We must rely primarily on a sparse fossil record and other clues from their dwellings to form a picture of them. In preparation for my previous book, What Comes After Homo Sapiens?, I researched the most likely paths to the next human species. While my conclusions are speculative, our ability to look ahead is on much firmer ground than our tools to study the past.

The ways we look at both the past and future have changed. We now have detailed, written documentation of our more recent history, including a comprehensive look at the most important biological evidence: our genome. Amazingly, we have also been able to coax out enough DNA from the fossils of Neanderthals and other extinct species to recreate their genomes. That has given us a tremendous boost in understanding our past and has opened up a new field of study called paleogenomics. Still, we are limited to the study of the genomes from only a handful of individual Neanderthals and other extinct humans, compared to our current databases of millions of individuals. So, many mysteries regarding our past remain. That said, however, our vast current data sources, combined with our computational capabilities, now enable us to make a more accurate prediction of our future trajectory.

There is much in today’s popular science literature that envisions possible futures for humanity. Books like Homo Deus by Yuval Noah Harari, Cosmosapiens by John Hands, and Homo Evolutis by Juan Enriquez and Steve Gullans, all provide projections of the evolution of Homo sapiens over the next couple of centuries. The focus of these books, however, is mostly cultural and broad-based. Much of their focus is on the social and political aspects affected by our sciences and institutions and paints a picture of only what Homo sapiens might be like in the future. None deal with the more specific scientific questions regarding speciation: exactly when and how a new species will arise from Homo sapiens in the course of evolution. Evolution of Homo sapiens is a description of how we change over time. Speciation is how Homo sapiens transitions to a totally new human species. This book focuses on speciation.

My 2017 book, What Comes After Homo Sapiens?, served to document my research on this subject. Readers were most interested in the science and evidence regarding the answer to the book’s title question. The Fourth Great Transformation has been updated to the present and tells this non-fiction story in a broader popular-science manner, albeit one with a speculative ending.

The Fourth Great Transformation ends with the emergence of a new human species as a result of our using our two most advanced tools: artificial intelligence (AI) and genetic engineering. I describe in detail one possible scenario as to how this could occur. It is only one potential scenario out of many that could have been chosen.

Each of the first three great transformations deserves a book in itself. All are equally momentous in the history of life on Earth leading up to this Fourth Great Transformation, but they will be described only briefly here.


The Earth has existed for about 4.5 billion years. The First Great Transformation was the emergence of life on this planet about 3.8 billion years ago. Exactly what was this first life form is unknown to us, as is where on Earth it occurred or even whether it originated on Earth or was seeded from elsewhere in the cosmos. The only evidence of these original life forms in existence today are the ubiquitous single-celled organisms called bacteria and archaea,(1) which together are called prokaryotes. All other life forms – including us – evolved from these entities.



After those first single-celled prokaryotes appeared on Earth, not much happened with them for the next two billion years. Think about that. Then suddenly (in evolutionary terms), a new life form took over about 1.8 billion years ago. This happened when a species of archaea engulfed a species of bacteria, and those prokaryote cells transitioned into the eukaryote cell. The most dramatic difference between a prokaryote and a eukaryote was that eukaryote cells then specialized into team players to become multi-cellular organisms. Some cells become heart cells, others skin cells, leaf cells, root cells and so forth, specializing into all the various cells that make up plants and animals.

Once the forces of evolution were unleashed by this Second Great Transformation, countless variations in life occurred and led to billions of new species of plants and animals. Only a small fraction of these species remains alive today. Most of that evolution occurred over 1.5 billion years and long before anything like a human appeared on Earth. The immediate precursors to humans date back to only about 7 million years ago. It is still being debated exactly who were the first humans – possibly Homo habilis or Homo ergaster. They did not arrive until about two million years ago. But, when they did, it ushered in The Third Great Transformation.



That Third Great Transformation was the development of our human brain, which began in earnest at about that point two million years ago. This transformation from the relatively primitive, ape-like brain to our amazing and mysteriously complex neocortex has brought us intelligence, consciousness, language and tool-making capabilities unparalleled in nature.

This Third Great Transformation ultimately enabled us to create two particularly remarkable tools – AI and genetic engineering. It is these tools, used in combination, that will generate The Fourth Great Transformation.



The first three great transformations are fact. The fourth is speculation, albeit based on hard scientific evidence and our rapidly accelerating tools capabilities. The disciplines of evolutionary biology, taxonomy, species and speciation, genetics and genomics, AI, neuroscience, nanotechnology and genetic engineering (among others) all inform the study of our future evolution as a species.

A study of the literature of those disciplines and consultation with experts in those fields led me to the following hypotheses:

  1. Another human species, let’s call it Homo nouveau (‘new man’), will co-exist with us within the next two centuries.
  2. Homo nouveau will not emerge naturally in the course of evolution, as we Homo sapiens (‘wise man’), did. Instead, it will be the result of our tool use.
  3. Those tools will be AI and genetic engineering.



We are already going through the preliminary phases of genetically altering thousands of other species. In the short period of several decades, we have come to the point where GMOs (genetically modified organisms) have become a routine part of agriculture and our food supply. They have become commonplace with regard to plants, and in the past few years have extended to animal foods like salmon and to so-called pharm-animals, genetically modified to produce drugs for human consumption.

The extension to GMHs (genetically modified humans) has also begun, with our attempts to cure genetic diseases and even cancer. It is only a matter of time before we not only alter species, but also perform genetic manipulations that lead to entirely new ones, including next-generation humans. This won’t happen suddenly. The more we learn about our genome, the more complicated we find it. And, although tools like CRISPR and other genetic engineering methodologies are being used more universally, we remain a long way from being able to apply them safely and confidently in most situations.

This is where our other advanced tool, AI, comes in. We will use AI to overcome the complexities and problems in genetic engineering. The first three great transformations have all been sequential, with each subsequent one depending on the previous. The Fourth Great Transformation, however, will be different; it will be caused and created entirely by the collective brains of Homo sapiens.



The first three great transformations were each created by myriad random natural events over very long periods of time. Each was dramatic, mysterious and highly unlikely. Each of their probabilities was so remote that the probability that all three have occurred on Earth (or anywhere) seems extremely small. Even our own existence was unlikely. As the late paleontologist Steven Jay Gould said, “If we could replay the game of life again and again … the vast majority of replays would never produce (on the finite scale of a planet’s lifetime) a creature with self-consciousness.”(2) And yet, here we are, on the cusp of a Fourth Great Transformation.

But this one will be different in a rather striking way – when Homo nouveau emerges, we will be aware of it. In the entire history of life on Earth, there has never been a species that was aware that another species has evolved from it. In fact, there has never been another species that even had a concept of species. We, Homo sapiens, made up that concept. It is a figment of what we call our fictive thinking – our unique ability to think and talk about concepts that have no objective reality. Fictive thinking allows us to think symbolically about things in ways that enable us to plan ahead and cooperate to an extent far more effectively than any other species.

The first known discussion of the concept of species is from the ancient Greeks. That’s only a couple of thousand years ago – long after any other human species was alive. It is doubtful that any other human species thought about this, let alone recognized the transition to another human species.

More importantly, The Fourth Great Transformation will mean that we have transformed evolution itself. The true greatness of this transformation will be that evolution in the human lineage will never be the same as in the past. Although Darwinian natural selection will continue, our genetic manipulations will usurp the normal and natural evolution that has led to new human species in the past.

And we will continue to preempt those human speciation processes for as long into the future as humans exist.


References and Footnotes:
  1. Archaea are microscopic single-celled organisms that differ from Bacteria in the nature of the cell walls and certain chemical processes. They are ubiquitous in nature, including within the human intestinal tract and on human skin, and are often found in extreme environments.
  2. Gould, Steven, Full House, New York, Harmony Books, 1996, p.175


If you’d like to find out more information about The Fourth Great Transformation, please see Don’s previous blogs.


DON SIMBORG is a graduate of the Johns Hopkins School of Medicine, and former faculty member at both the Johns Hopkins and University of California San Francisco schools of medicine. He is the founder of two electronic medical records companies and is a founding member of the American College of Medical Informatics. He served on the Computer Science and Telecommunications Board of the National Academics of Science. He and his wife, Madeleine, have two children and four grandchildren and live in California.



Suggested Reading

A new human species will soon come to co-exist with us. This new species, ‘Homo nouveau, will be created using artificial intelligence and genetic engineering; both important tools which are in their infancy. Not only are the science and technology relatively new, but their implications in the mind of the general public are also only just beginning to enter our collective consciousness. This book expands on the research done for the author’s pervious book, What Comes After Homo Sapiens?

Written by a medical professional and independent consultant to healthcare IT companies, The Fourth Great Transformation explores the questions of what this new species will look like, how we as humans will get along with them, and the potential threats and opportunities that will come along with genetically modified humans.

More information