This seems like such a cool idea for a website, but then it's let down by the fact that it's actually First Known Photographs of Living Specimens Posted To INaturalist.com. I thought it'd be a bunch of photos from the 1800s but it's a bunch of photos from the 2020s.
For example here is the actual first known photo of a domestic cat: https://i.imgur.com/OKtFMos.jpeg