Daniel Everett, who has studied unusual languages, says the evidence from Homo erectus’s tools and artifacts of over 100,000 years ago show that they must have had language:
”Erectus settlements show evidence of culture – values, knowledge structures and social structure. This evidence is important because all these elements enhance each other. Evidence from the erectus settlement studied at Gesher Benot Ya’aqov in Israel, for example, suggests not only that erectus controlled fire but that their settlements were planned. One area was used for plant-food processing, another for animal-material processing, and yet another for communal life. Erectus, incredibly, also made sea craft. Sea travel is the only way to explain the island settlements of Wallacea (Indonesia), Crete and, in the Arabian Sea, Socotra. None of these were accessible to erectus except by crossing open ocean, then and now. These island cultural sites demonstrate that erectus was capable of constructing seaworthy crafts capable of carrying 20 people or more. According to most archaeologists, 20 individuals would have been the minimum required to found the settlements discovered. Daniel Everett, “Did Homo Erectus Speak” At Aeon (February 28, 2018)”
He certainly has a point. It is hard to imagine organizing the construction, launch, and navigation of such craft without language. How would an erectus get co-operation without explaining the idea?
News, “Cognitive scientist: Earliest humans, Homo erectus, had language” at Mind Matters News
Note: Yes, it’s that Daniel Everett, about whom Tom Wolfe wrote The Kingdom of Speech (2016), contra Noam Chomsky (1928–).
You may also wish to read:
Why Noam Chomsky is a great scientist of our era. He singlehandedly rid linguistics of a stultifying (and technically mistaken) behaviorism (Michael Egnor)
Did the human mind originate in telling ourselves stories? A philosopher and writer tries to account for the jump from animal to human by wholly natural means. (Denyse O’Leary)
and
The real reason why only human beings speak. Language is a tool for abstract thinking—a necessary tool for abstraction—and humans are the only animals who think abstractly. (Michael Egnor)