Neanderthals have developed the hearing ability to support a vocal communication system as effectively as modern human speech, according to new research led by scientists from Universidad de Alcalá.
Neanderthals. Image Credit: University of Utah via kued.org.
The linguistic capabilities of the Neanderthals have long been an area of active research and debate among scientists, albeit with little resolution.
The last two decades are increasingly archaeological discoveries documenting complex behaviors in this sister species Homo sapiens. This is linked to the possible presence of language, as it seems reasonable that such behavior requires the presence of a complex and effective oral communication system.
Nevertheless, another view holds that the characteristic features of human language, which are not absent in other organisms, include a symbolic element as well as a recursive syntactic process called merging.
The latter process uses in its simplest way two syntactic elements and compiles them to form a collection, and is claimed to be exclusive to Homo sapiens and did not appear earlier than 100,000 years ago.
The detection of the presence of symbolism and syntactic processes in the course of human evolution is currently beyond the possibility of paleontology.
Nevertheless, the study of human fossils may be the key to determining whether human species, and in particular the Neanderthals, possess the anatomy necessary to produce and consider an oral communication system as complex and efficient as human speech. common language for language.
In other words, although paleontology cannot study the evolution of the ‘software’ of language, it can contribute to our understanding of the evolution of the ‘hardware’ of speech.
“For decades, one of the most important questions in human evolutionary studies was whether the human form of communication, spoken language, was also present in any other kind of human ancestor, especially the Neanderthals,” said Professor Juan Luis Arsuaga, a researcher at the Centro Mixto (UCM-ISCIII) de Evolution y Comportamiento Humanos en die Departamento de Geodinámica aan die Universidad Complutense de Madrid.
Using high-resolution CT scans, Professor Arsuaga and his colleagues developed 3D models of the structures of Homo sapiens, Neanderthals, and the Sima de los Huesos hominins, considered ancestors of the later Neanderthals.
They then incorporated the new data into a software-based model, developed in the field of auditory bio-engineering, to estimate the hearing capabilities up to 5 kHz, covering most of the frequency range of modern human speech sounds.
Compared to the Sima de los Huesos hominins, Neanderthals heard slightly better between 4-5 kHz, which looks more like modern humans.
In addition, the researchers calculated the frequency range of maximum sensitivity, technically known as the occupied bandwidth, in each species.
“The occupied bandwidth is related to the communication system, so a wider bandwidth can use a greater number of easily distinguishable acoustic signals in the oral communication of a species,” they explained.
“This in turn improves the efficiency of communication, and the ability to deliver a clear message in the shortest amount of time.”
The Neanderthals had a wider bandwidth compared to their ancestors of Atapuerca, who in this feature look more like modern humans.
“That’s really the key. The presence of similar hearing aids, especially bandwidth, shows that Neanderthals possessed a communication system that was as complex and efficient as modern human speech, ” said Professor Mercedes Conde-Valverde, a researcher at the Cátedra de Otoacústica Evolutiva y. Paleoanthropology at the Universidad de Alcalá.
“One of the other interesting results from the study was the suggestion that Neanderthal speech is likely to include an increased use of consonants,” said Professor Rolf Quam, a researcher in the Department of Anthropology at Binghamton University, Department of Anthropology at the American Museum , said. Science, the Universidad de Alcalá and the Centro Mixto (UCM-ISCIII) de Evolución y Comportamiento Humanos.
The team’s results show that Neanderthals had the same ability to produce the sounds of human speech, and that their ears were ‘tuned’ to observe these frequencies.
This change in auditory abilities in Neanderthals, compared to the ancestral Sima de los Huesos hominins, is consistent with archaeological evidence for increasingly complex behavioral patterns, including changes in stone tool technology, domestication of fire, and possible symbolic practices.
‘These results are particularly gratifying. We believe, after more than a century of research into this question, that we have given a conclusive answer to the question of the Neanderthal speech ability, ‘says dr. Ignacio Martinez, a researcher at the Centro Mixto (UCM-ISCIII) de Evolución y. Comportamiento Humanos and the Department of Geodynamics at the Universidad Complutense de Madrid.
The findings were published in the journal Natural ecology and evolution.
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M. Conde-Valverde et al. Neanderthals and Homo sapiens had similar hearing and speech ability. Nat Ecol Evol, published online on March 1, 2021; doi: 10.1038 / s41559-021-01391-6