Breed (1995-2007) is a computer program that uses artificial evolution to grow very detailed sculptures. The purpose of each growth is to generate by cell division from a single cell a detailed form that can be materialised. On the basis of selection and mutation a code is gradually developed that best fulfils this "fitness" criterion and thus yields a workable form.

The designs were initially made in plywood. From the year 2000, the sculptures can be made from nylon and stainless steel by using 3D printing techniques. This automates the whole process from design to execution: the industrial production of unique artefacts.