Fractals = Complex shapes which look the same at a wide variety of scale factors.
Fractals are one of my favorite topics because it is a unique synthesis of art & science which trancends the qualities we normally look for in those disciplines. This post "Fractals for Food" has a nice collection of pictures of fractal geometry in natural forms.
I can't believe that this particular cauliflower, Chou Romanesco, even exists! It looks like it was made with a computer program.
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