Dear Pharo users, I develop software dedicated to the simulation of plant development and 3D architecture. In the past, I used Java, but I am very interested in translating code in Pharo. I appreciated very much the language and the course. I have a question for you all : During plant development (ontogeny), new organs appear, that are gradually tranformed. For example, a bud can make a flower, and then a fruit. Organs are conveniently modelled as classes. During the course, I learned that it was better to make several classes (bud, flower, fruit) instead of a "fat class" such as "reproductive organ" with many attributes and stages (bud stage, flower stage, fruit stage). I wonder how to transform an object into another one, to represent for example the fact that the flower may become a fruit. Maybe a naive question ? Thanks for your lights ! Loïc