One of the persistent questions about language origins asks when did it begin. This blog has always favored a very ancient date. Truth is, I suspect the earliest Homo genus had language, in the sense of using joint attention to consider a topic. At that stage speech might have been no more complicated than a modern 24-month-old toddler today. In other words, they could speak phrases, but not full sentences with two nouns and a verb. The evidence for that is two-fold: (1) all healthy, modern humans go through such a developmental phase today, and (2) chimpanzees and gorillas are already smart enough to use language at this level. I’m fully in tune with Michael Tomasello’s argument that apes lack the motivation to use language, not the smarts.
Meanwhile, the elite consensus seems to be that language is no more than 100 thousand years old, which is to say that it appeared a hundred millennia after the appearance of Homo sapiens. Their evidence is that symbols only become a regular feature of archaeological remains at about that time. The many biological adaptations for speech must therefore have evolved for some other purpose. What other purpose might that be? Can’t say, but it must be so.