International audienceThat creole languages resemble each other beyond the diversity of their lexifiers and formative environments is a fact. Similarity should not be overstated, however, as creole languages also differ from each other in important ways. Hence the fundamental issues of creole studies: why are Creoles similar and what makes them different? What kind of a language group do they constitute? A genetic family they certainly are not, nor are they a typological group: creole languages do not constitute a type of their own. Assuming universal grammar viewed as a language bioprogram (LB) to be the principle of creole similarity strongly overstates this similarity. Moreover there are reasons to doubt the reality of the LB.Actually th...