As a field of scientific expertise, semiotics has the interesting property of being a relevant tool for understanding how scientists represent any domain of research, including the semiotic domain itself. This feature is particularly expressive in the case of biology, as it appears to be the case that a certain range of biological phenomena are of a semiotic character. However, it is not consensual the extent to which semiotics pervades biology. This paper deals with this issue for the particular case (...) of developmental biology, stressing the role of semiotics-as-a-discipline in delimiting the extent of semiotics-as-a-natural-phenomenon and, specifically, in disentangling semiotic mechanisms from semiotic metaphors aimed at clarifying non-semiotic developmental mechanisms. (shrink)