Sponges are the most basal metazoan organisms.

Light Inside Sponges:
https://www.sciencedirect.com/science/article/abs/pii/S0022098108004085?via%3Dihub

cloud2ground (v.1)

"The unthought would have to make your machines uncomfortable, the uninscribed that remains to be inscribed would have to make their memory suffer. Do you see what I mean? Otherwise, why would they ever start thinking? We need machines that suffer from the burden of their memory."

Lyotard, The Inhuman: Reflections on Time (via Anil Bawa-Cavia)
https://technosphere-magazine.hkw.de/p/The-Inclosure-of-Reason-ecTsvnENeC1GXtmgRNaMH9

That was the beginning of the end, I guess...
when they finally started looking into us.

cloud2ground (v.1)

Sloth Function