Hormones, sex accessory structures, and secondary sexual characteristics in amphibians: A focus on breeding glands

In the first edition of Volume 2 of Hormones and Reproduction of Vertebrates Sever and Staub (2011) reviewed sex accessory structures and secondary sexual structures in amphibians, and the role hormones play in their development. Herein, we delve deeper into one of the more exciting sexual structures of amphibians: glands involved in breeding. A subcategory of breeding glands, courtship glands, functions as pheromone-producing glands that elicit courtship behaviors in the opposite sex. Amphibians have rapidly become the model for understanding the evolution of pheromonal communication in vertebrates through the study of courtship glands in plethodontid salamanders. In the following chapter, we will review the different types of breeding glands in amphibians and highlight innovations in our understanding of their hormonal control, evolution, and function.