Who loves ya, baby?
We're becoming more distinctively human.
trivial but important point to realise, and the only indisputable response. Once accepted you can have the debate understanding the distinction is very ideological, focused on desired outcomes, hopes and fears and like you say the main question of what does it mean to be human? Does this thing, this behaviour threaten my idea of what it means to be human?if you define what's natural to mean what exists, then everything is trivially natural