Can epigenetics solve the case of the midwife toad?--a comment on Vargas.

In a recent article in this journal, A. O. Vargas (2009. J Exp Zool B (Mol Dev Evol) 312:667-678) suggests to interpret the controversial midwife toad experiments of the early 20th century zoologist Paul Kammerer in the context of epigenetic inheritance. For information on Kammerer's work he resorts to a popular science book (Kammerer, '24. The Inheritance of Acquired Characteristics). However, the study of Kammerer's original publications reveals that there are substantial misunderstandings in Vargas' treatment of the subject. While Vargas' general idea-invoking epigenetic effects as an explanation of Kammerer's findings-remains attractive, at least two key aspects of his model need to be revised. Clarification of these issues is an important prerequisite for any experimental design with the aim to (dis)prove Kammerer and to establish a (potential) epigenetic basis of his observations about the mating behavior in midwife toads.