Here is an amusing example of marbling created by small water spiders: gerrids. John Bush is a professor at MIT who specialises in applied mathematics. He is known for his work on surface tension and fluid dynamics. So John Bush is a pretty brilliant guy but certainly not someone you would expect to produce this kind of thing. Because yes, John Bush turns everything he studies into art, without even meaning to. A few years ago, he published The Hydrodynamics Of Water Strider Locomotion, the water strider being the gerridaes, the water spiders that float on ponds.
https://www.vice.com/fr/article/8qvnv4/gliding-insects-create-accidental-water-art