Fractals are geometric shapes that are, either as a whole or in part, self-similar. As well as being interesting mathematical objects, they also occur in nature. Above is a photograph of a Romanesco broccoli set against a black background. Self-similarity can be observed in the inflorescence (the bud), which is approximately a scaled version of the broccoli as a whole, each of which are made up of yet more scaled versions of the broccoli. In addition, the branched meristems making a logarithmic spiral, a feature that can be seen in many other fractals.