Math in… Nature

A fractal is a geometric structure that has self-similarity at infinitely many different scales. No matter how far you zoom in, you will find small features that look like scaled-down versions of the whole shape or its larger features.

While real-life objects become particles when you zoom in far enough, many of them are still fractal-like, with self-similarity at many scales like the Romanesco broccoli on the cover image.

A bough of a tree looks like a small tree, as do its branches and their branches. This fact is often used to model trees with L-systems.

What other things have you seen with this sort of self-similarity?