Dermatologists when telling young patients that toads may have caused their warts. The word "toad" itself is derived from the old English word tadige, which is of unknown origin, without cognates in other languages, and has obvious negative connotations when applied to people. The common European toad, Bufo bufo, is used for studying moulting and recently has had its epidermal kinetics and epidermal homeostasis investigated in detail. Dermatologists are interested in epidermal kinetics because of psoriasis, the ichthyoses, epidermal malignancies, and the response of the epidermis to chemotherapeutic drugs and the retinoids. When we read studies of the kinetics in those disorders, we may not be dispassionate students and often carry with us all of our experience and hang-ups concerning the disease in question. In thinking about the studies in the toad, hopefully there is less emotional investment.
Since man and toad first met each other, it has been known
Goldsmith LA. Toads and Psoriasis. Arch Dermatol. 1986;122(8):939-940. doi:10.1001/archderm.1986.01660200111029