When thinking of amphibians, frogs and toads are usually the first to come to mind. Both are widely found all over the world and come in a dazzling array of colors, sizes and shapes. But what if you are unsure if what you are looking at is a frog or a toad? They both have similar looking bodies and eat similar things. But there is one defining characteristic that differentiates toads from frogs. Frogs typically have smooth skin covering their bodies while toads are covered in warts. The amount of warts will vary from species to species as some will have only a few warts on their backs while others will be covered from head to toe. Are these warts really warts in the same definition as human warts? Or are they something completely different?
First of all, the warts that humans get on the various regions of the body are caused by an infection of Human Papilloma Virus or HPV. An HPV infection is only spread from human to human. The warts on a toad are not caused by HPV, which debunks the old wives tale that touching a toad will give you warts.
The warts that toads have are actually small pockets of a poisonous toxin that is secreted from the toad’s skin when the toad is in danger of being eaten by a predator. This toxin is also highly irritating if touched to bare skin if a distressed toad is being handled.
Most of the well-known warted toads belong to the family Bufonidae, also known as the true toad family and can be as small as a quarter as in the case of the Oak toad (Bufo quercicus) or as large as a dinner plate as in the case of the giant Cane toad (Bufo marinus) that has invaded Australia in the failed attempt to control the cane beetle population. All toads belonging to this family have warts which will secrete toxin. The Cane toad is known to have the most dangerous toxin and can cause serious illness in humans and even death in children and pets. The Cane toad’s success in over-populating Australia is due in part to its dangerous toxin as it does not have any natural enemies and breeds freely.
Warts are what make toads unique and different from frogs. One of the most beautiful toads known to science is the Golden toad (Bufo periglenes). Unfortunately, this toad has not been sighted since the 1980s and is most likely extinct. This beautiful example of a warted toad is just one of the many species of toads that may be extinct or close to extinction. It just goes to show that even the most beautiful animals may be covered in warts.