The science of bushfires is settled (part 2)

Have you noticed how chaotic and wasteful eucalypts are? They have branches that grow in all directions and lengths and they seem to be forever dropping dead bits off them. Why hasn’t natural selection tidied them up so their branches are all economically organised to maximise access to light like beautifully ordered pines or symmetrical oaks? A eucalyptus tree actually looks like a whole lot of trees fighting with each other for access to the light. In fact, a trick to painting a eucalypt is to simply place a lot of grey-green blobs near each other and then connect them with stalks to a central trunk, and voilà, you have a eucalypt.

What this chaotic structure suggests to me as a biologist is that eucalypts are an ‘upstart species’—a species that has hit upon some novel, beats-all strategy that has allowed them to develop and proliferate at such a rapid rate that natural selection hasn’t had time to refine the design of their new opportunity.