After the somewhat painterly approach of the shot above, below is a sharply etched photo that shows an artifact which looks something like an ancient painting.
Cave painting? No, it's obviously just a part of the same concrete walkway, as I'm sure the expansion joint makes clear. I think it looks like a representation of an antelope, but maybe that's just me.
Raindrops falling in an otherwise still puddle. The overlapping waves show clear patterns of interference and reinforcement as the peaks and troughs interact.