This computer dialog also emphasizes constructing scientific explanations for observed phenomena. The students descend onto a planet and observe the inhabitants of the planet. Some are big and some are small; some have curled horns and some straight horns; some have dark eyes and some light eyes. The first empirical task is to discover which combinations can have offspring. The eventual aim is to discover the laws of inheritance of individual characteristics.
Students can make ``matings'' of pairs and observe the resultant offspring's characteristics. The explanation for the inheritance patterns, eventually determined through trial and error and hypothesis formation, follows Mendelian genetics. Students discover these laws by analyzing the evidence, just as in the previous dialogs of this type.