Marilyn was unrepentant. I admit that it's not the kind of thing you expect to turn up in a public opinion poll on the fascination of animals. In fact it doesn't even sound like an animal. But it is an animal, a kind of amoeba, and it's most definitely fascinating. Somehow this tiny, unintelligent creature manages to create the most spectacular patterns.
Slime mould builds beautiful spirals.
The spirals are an example of pattern formation. Symmetry classifies natural patterns, and can even explain many of them, such as the stripes on a tiger or the spots on a leopard. Symmetry also lies behind some of the puzzling abilities of mirrors. A race of asymmetric aliens would ask very different questions about mirrors. Reflections in mirrors are just one of several kinds of symmetry.