This is a profound inquiry, originating from deep within our past: When did human language, as we recognize it today, come into existence? A recent examination of genomic data indicates that our distinct linguistic ability was likely present at least 135,000 years ago. Therefore, language may have started to be socially utilized around 100,000 years ago.

Our species, Homo sapiens, is approximately 230,000 years old. Estimates regarding the origins of language vary significantly, based on various types of evidence, from fossils to cultural relics. The writers of the new assessment adopted an alternative method. They posited that since all human languages likely share a common ancestry — which the researchers strongly believe — the crucial question is how far back in time regional groups began to disperse across the globe.

“The reasoning is quite straightforward,” states Shigeru Miyagawa, an MIT professor and co-author of a recent paper summarizing the findings. “Every population diverging around the world possesses human language, and all languages are interrelated.” Based on what the genomic data reveal regarding the geographic separation of early human groups, he adds, “I think we can assert with a considerable degree of certainty that the initial division occurred about 135,000 years ago, meaning human language capability must have existed by that time, or even earlier.”

The article, “Linguistic capacity was present in the Homo sapiens population 135 thousand years ago,” is published in Frontiers in Psychology. The co-authors include Miyagawa, who is a professor emeritus of linguistics and the Kochi-Manjiro Professor of Japanese Language and Culture at MIT; Rob DeSalle, a principal investigator at the American Museum of Natural History’s Institute for Comparative Genomics; Vitor Augusto Nóbrega, a faculty member in linguistics at the University of São Paolo; Remo Nitschke, of the University of Zurich, who contributed to the project while at the University of Arizona’s linguistics department; Mercedes Okumura of the Department of Genetics and Evolutionary Biology at the University of São Paulo; and Ian Tattersall, curator emeritus of human origins at the American Museum of Natural History.

The new paper investigates 15 genetic studies of various kinds, published over the last 18 years: Three utilized data regarding the inherited Y chromosome, three analyzed mitochondrial DNA, and nine were whole-genome examinations.

Overall, the findings from these studies imply an initial regional divergence of humans approximately 135,000 years ago. This suggests that following the emergence of Homo sapiens, groups of individuals subsequently dispersed geographically, leading to the development of some genetic variations over time among the various regional subpopulations. The amount of genetic diversity identified in the studies enables researchers to estimate when Homo sapiens remained a single regionally unified group.

Miyagawa states that the studies collectively offer increasingly converging evidence concerning when these geographic separations began to occur. The first evaluation of this nature was conducted by other researchers in 2017, but they had fewer genetic studies to reference. Now, a richer array of published data is available, which, when compiled, indicates that 135,000 years ago is likely the time of the first bifurcation.

The new meta-analysis was feasible because “in terms of quantity, we have more studies, and in terms of quality, it’s a narrower temporal window,” remarks Miyagawa, who also holds a position at the University of São Paulo.

Like numerous linguists, Miyagawa is convinced that all human languages are demonstrably interconnected, a concept he has explored in his own research. For instance, in his 2010 book, “Why Agree? Why Move?” he examined previously uncharted similarities among English, Japanese, and certain Bantu languages. There are over 7,000 recognized human languages worldwide.

Some researchers have suggested that language capacity originated a couple of million years ago, based on the physiological features of other primates. However, for Miyagawa, the focus is not on when primates could produce specific sounds; rather, it is when humans possessed the cognitive capability to create language as we know it, amalgamating vocabulary and grammar into a system that generates an infinite array of rule-based expressions.

“Human language is qualitatively distinct because it comprises two components, words and syntax, working in unison to form this intricate system,” Miyagawa asserts. “No other species exhibits a comparable structure in their communication systems. This endows us with the capacity to formulate highly sophisticated thoughts and convey them to others.”

This perspective on the origins of human language also suggests that humans possessed the cognitive capability for language for a considerable duration prior to the formation of our initial languages.

“Language functions as both a cognitive framework and a communication tool,” Miyagawa asserts. “I suspect that before 135,000 years ago, it originated as a private cognitive system, but rather swiftly transformed into a communicative medium.”

So, how can we ascertain when uniquely human language was first utilized? The archaeological record proves invaluable in this context. Approximately 100,000 years ago, evidence indicates a widespread emergence of symbolic activities, ranging from meaningful markings on objects to the utilization of fire to produce ochre, a decorative red pigment.

Much like our complex, highly generative language, these symbolic actions are carried out by humans alone, devoid of similar practices by other creatures. As noted in the paper, “behaviors conducive to language and the consistent application of symbolic reasoning are only observable in the archaeological remains of H. sapiens.”

Among the co-authors, Tattersall has notably advanced the viewpoint that language acted as a catalyst for symbolic reasoning and other organized behaviors.

“Language was the impetus for modern human behavior,” Miyagawa asserts. “In some manner, it stimulated human cognition and fostered these types of actions. If our hypothesis holds true, individuals were learning from one another [due to language] and promoting innovations similar to those observed 100,000 years ago.”

However, as the authors acknowledge in the paper, other scholars contend that there was a more gradual and broadly supported evolution of new activities around 100,000 years ago, concerning materials, tools, and social coordination, with language playing a role in this process, yet not necessarily being the central driver.

For his part, Miyagawa recognizes that there is ample scope for further advancements in this research domain but believes endeavors like the current paper represent significant strides towards painting a more detailed picture of language’s development.

“Our methodology is very empirically grounded, based on the latest genetic insights into early Homo sapiens,” Miyagawa explains. “I believe we are following a commendable research trajectory, and I hope this will inspire more investigation into human language and evolution.”

This research was partially supported by the São Paolo Excellence Chair awarded to Miyagawa by the São Paolo Research Foundation.