For a long time, as you probably remember, it was denied that Neandertal could even speak; the obnoxious godfather of mtDNA even claimed that speech lived on mtDNA, and that Neandertal died out as a “village idiot” which couldn’t speak.
That was so obnoxious, he should have been suspended and brought up on a tenure hearing, and if not fired then censured or forced into retirement. He wound up dying of cancer.
Yes and I’m going to read that book you always recommend, but I still don’t know how they know what Neadertal speech sounded like.