There was a pretty crazy theory from Soviet scientist Porshnev, who stated that neanderthals/paleoanthrops "created" humans/neoanthrops (like domesticated animals) and used them as food. They've used suggestion and language to control them, and that was one of reasons for language evolution.

Those who think that he was right now say that this system may work even today, although in different style.

25D0%259E_%25D0%25BD%25D0%25B0%25D1%2587%25D0%25B0%25D0%25BB%25D0%25B5_%25D1%2587%25D0%25B5%25D0%25BB%25D0%25BE%25D0%25B2%25D0%25B5%25D1%2587%25D0%25B5%25D1%2581%25D0%25BA%25D0%25BE%25D0%25B9_%25D0%25B8%25D1%2581%25D1%2582%25D0%25BE%25D1%2580%25D0%25B8%25D0%25B8">https://translate.google.com/translate?sl=ru&tl=en&u=https://ru.wikipedia.org/wiki25D0%259E_%25D0%25BD%25D0%25B0%25D1%2587%25D0%25B0%25D0%25BB%25D0%25B5_%25D1%2587%25D0%25B5%25D0%25BB%25D0%25BE%25D0%25B2%25D0%25B5%25D1%2587%25D0%25B5%25D1%2581%25D0%25BA%25D0%25BE%25D0%25B9_%25D0%25B8%25D1%2581%25D1%2582%25D0%25BE%25D1%2580%25D0%25B8%25D0%25B8

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