This project contains an implementation of the "Blind Watchmaker" algorithm as a relational growth grammar in the language XL (see the file Biomorph.xl). When the relational growth grammar is initialised, four individual biomorphs are created and shown in the 3D view. You can select one individual by clicking on the small sphere at its base. Now ensure that the panels of the RGG layout are visible (choose this layout in the menu Panels/Set Layout). You will see the RGG toolbar with the buttons run, Run run, Stop, and Reset. A click on run then creates a new generation of individuals based on the genome of the selected parent (asexual reproduction). If you select two individuals (the Ctrl key has to be pressed while clicking the second individual) and invoke run, the genomes of both parents are combined in a crossing-over step, then a new generation is created (sexual reproduction). Accumulated mutations in a certain direction (biassed by the user) lead to a shortcut through the multidimensional genotypic and phenotypic parameter space, thereby arriving at "biomorphs", i.e. structures that look like animals or plants or possess other, "strange" morphologies.