On that note, we know that interbreeding between Neanderthals and (the ancestors of) modern humans happened during at least two periods: > Neanderthal-derived

On that note, we know that interbreeding between Neanderthals and (the ancestors of) modern humans happened during at least two periods: > Neanderthal-derived genes descend from at least 2 interbreeding episodes outside of Africa: one about 250,000 years ago, and another 40,000 to 54,000 years. Interbreeding also occurred in other populations which are not ancestral to any living person [0] ... which makes me think that it's more likely that both populations had the genomic capacity for language all the way back in the first "episode" 250k years ago as well (but to be clear, I'm saying it seems more likely to me, not that we can safely assume this must be true) . Yes, I know that "humans are impossibly horny" is a bit of a meme, but we're not just talking about sex here, but about having offspring that is successful enough within then-existing society over many generations, to the point where the Neanderthal DNA was absorbed into the common gene pool and survived all the way to this day. It seems very unlikely to me that that would happen unless both species were on a comparable level of mental capabilities. So we either both evolved language capabilities separately around similar times somewhere after 250k years ago, or already had the basis for it before our ancestral populations split and then later met again. [0] https://en.wikipedia.org/wiki/Neanderthal#Interbreeding https://en.wikipedia.org/wiki/Neanderthal#Interbreeding