Wait, wait, wait: One BILLION Years?

AstroBull has a question about the Numenera setting:

I have a question about the TTON time scale. In a previous AMA response, you mention "the setting of Numenera and Torment is Earth one billion years in the future, known as the Ninth World. A billion years is as far removed from us as we are removed from being single-celled organisms." This brings up questions regarding biological evolution. As far as I am aware, many/most characters in TTON will be recognizably human, though I'm sure with c...