«GENETIC TRANSFORMER»: how language emerged before Homo sapiens

Photo by Joyce Hankins on Unsplash

Forget everything you thought you knew about human origins! The latest scientific discoveries suggest that we are the result of a merger of at least two ancestral populations. They likely spoke different languages. But in the end, evolution chose us!

«GENETIC TRANSFORMER»

ccording to the latest scientific findings, modern humans most likely emerged somewhere in Africa between 50,000 and 300,000 years ago. Pinpointing the exact time and place remains a challenge for researchers, as evolution is a process with extremely long and complex dynamics. Fifty thousand years marks the lower boundary, when human remains appear that are virtually identical to modern Homo sapiens. Three hundred thousand years is the upper boundary, around which our species began to take shape.

Between these two rough points in time, members of the Homo genus still showed some differences from us — for example, in the shape of the chin, forehead, and brow ridges. Whether these individuals were our direct ancestors remains a matter of debate. However, according to a recent article by researchers from the University of Cambridge published in Nature Genetics, it was around this upper boundary that two ancestral populations of ours came into contact. This could help explain the subsequent diversity of traits.

Amazingly, we are in fact a «genetic transformer» — not the direct descendants of a single, continuously evolving human lineage. Our genus, Homo, appeared 2.8 million years ago. Since then, it split into various species that often coexisted — and possibly even interbred. These ancient Homo species already looked quite human, though their brains remained ape-like and were about half the size of ours.

Significant changes began to occur between 1.7 and 1.5 million years ago. During this period, the brain not only grew to nearly modern size but also acquired human architecture. Anthropologists can observe this clearly through the endocast — the pattern of folds and lobes left by the brain on the inner surface of fossilized skulls.

At the same time as this «upgraded» brain, Homo erectus — a direct ancestor of modern humans — also developed an «upgraded» culture around 1.5 million years ago. This is evident from the evolution of their tools. Scientists believe that such cultural innovations must have been accompanied by the emergence of a proto-language.

TWO «HUMANITIES» IN ONE

So, as early as 1.5 million years ago, we find a population belonging to the human genus that had almost everything we have — appearance, brain, cultural mechanisms, and language. Almost, but not quite — over a million years still remained before the emergence of anatomically modern humans! Meanwhile, around 1.5 million years ago, alongside the cultural and cognitive breakthrough, another event crucial to our evolution took place: the unified ancestral population of Homo erectus split into two groups, which then began to develop independently of one another.

Roughly 1.2 million years later, after a long separation, these two groups met again — and gave rise to modern humans. Their paths had been very different. One population went through a «bottleneck,» meaning it nearly went extinct but miraculously survived. Reduced to a critically small size, this population grew very slowly over a million years until, around 300,000 years ago, it reunited with the second group — which had apparently avoided such catastrophic events.

It’s likely that 80% of the genetic material in modern humans comes from the first group, from which Neanderthals and Denisovans also descended. These species began interbreeding with modern humans around 50,000 years ago, and left behind an estimated 1–7% of our genes. The remaining 20% of our genetics comes from the second population. Interestingly, this group initially contributed even more than the first — but over time, much of that contribution was «rejected» by evolution.

Today, its genetic legacy lies far from the regions of the genome associated with our functional genes. Nevertheless, scientists believe that this second population may have played a decisive role in human evolution by providing genetic material linked to brain function and neural processes.

TALKATIVE HEIDELBERG HUMAN

It’s possible that the representative of the second population — whose mixing with Homo erectus led to the emergence of Homo sapiens — was the Heidelberg human (Homo heidelbergensis). This species is considered a central figure in human evolution. Scientists previously believed that it was the common ancestor of both Homo sapiens and Neanderthals. However, it was later discovered that such a common ancestor lived around 1 million years ago, whereas Heidelberg humans inhabited parts of Europe and Africa approximately 600,000 to 200,000 years ago. They lived in large tribes, were skilled hunters and gatherers, and used tools made of stone and wood.

Judging by the absence of «laryngeal air sacs» — found in apes and known to hinder speech — and the structure of their hyoid bone, Heidelberg humans most certainly had articulate speech. Their hearing, based on the structure of their auditory ossicles, was tuned to fully human frequencies. The width of their spinal canal suggests they were capable of fine diaphragm control, which is also essential for articulate, vocalized speech.

Heidelberg humans belong to the same branch as Neanderthals, though their shared ancestor lived even earlier than the common ancestor of Neanderthals and modern humans. Does this mean the origins of language should be traced back to a time even earlier than 1 million years ago? One crucial detail: both we and Neanderthals share an identical gene — FOXP2. When this gene is damaged, it causes severe speech impairments. Since this gene is common to both us and Neanderthals, it’s logical to assume that it was inherited by both species — and possibly by Heidelberg humans as well — from even more ancient ancestors.

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THERE WAS MORE THAN ONE LANGUAGE

In any case, it’s clear that the origin of both our language and our species was neither sudden nor instantaneous. Today, Homo sapiens is the only surviving species of the Homo genus, though we still carry genetic material from other extinct species. What sets us apart from all other life forms on Earth is an exceptionally advanced and consciously controlled system of vocal communication. It likely began with a reduction in gesture-based communication, typical for apes, who are not adapted to using sound in this way.

For example, if you’re regularly crafting stone tools, your hands are always occupied — there’s no time for gestures, but you still need to communicate! Of course, this is only a hypothesis. But one way or another, evolutionary advantages favored those groups whose members could better understand subtle nuances in vocal signals. Speech changed many things in our ancestors, gradually giving them a more human form. The jaws receded, the larynx descended, the oral cavity became equal in length to the pharynx, and the tongue gained extraordinary mobility, both horizontally and vertically.

The «collections» of sounds, words, meanings, and the algorithms of their potentially endless combinations generated by the vocal apparatus had to be stored somewhere. Thus, brain development progressed in parallel with the development of language. All of this was an evolutionarily very lengthy process that began long before the emergence of anatomically modern humans. Moreover, since there were many Homo species, it’s possible that language was «invented» multiple times throughout evolution.

The world’s current languages trace back to a single proto-language only because all the others died out along with their speakers. But when and how did that one arise? Scientists have some ideas about that, too.

HOW OUR LANGUAGE EMERGED

Linguists have determined that Proto-Indo-European was spoken as recently as 6–7 thousand years ago. The proto-language of the Nostratic macrofamily — which includes not only Indo-European, but also Uralic, Altaic, Dravidian, Kartvelian, and other languages — existed around 14,000 years ago. From there, we can delve deeper into history, comparing data from the Nostratic macrofamily with other macrofamilies, such as the Sino-Caucasian…

Today, humanity speaks more than 7,000 languages. However, new research by linguists at the Massachusetts Institute of Technology shows that they all stem from a single root — a language that existed long before our species split into distinct populations 135,000 years ago. This time marker is determined through comprehensive genomic analysis. From that point on, the linguistic family tree begins to branch out.

Around 100,000 years ago, a verbal revolution occurred, which became embedded in the behavior of Homo sapiens. This is clearly reflected archaeologically — in the appearance of symbolic practices such as personal ornaments, burial rituals, and systematic engravings. The gap between the emergence of human language and its widespread presence in the archaeological record is explained by the idea that evolution needed some time to reach this new, «symbolic» level of communication.

Before this, such behaviors were only observed sporadically. But humans seemed to learn from each other at an increasingly rapid pace — something facilitated by the presence of language. They also began to reward various types of symbolic innovations, like perforated shell beads. In turn, this encouraged a certain type of thinking, behavior, and speech. And now, after 2.8 million years of evolution, we have the unique ability to generate very complex thoughts — and share them with others.

Original research: