While the African clawed frog lacks the lurid colours of poisonous frogs, instead blending into its watery environment, any snake unlucky enough to swallow it will have an unpleasant surprise.
In a 1988 paper published in Pharmacology Biochemistry and Behavior, researchers discovered that African clawed frogs that were fed to American water snakes induced yawning in the reptiles.
This slowed down the snake’s digestion of the frogs – buying them enough time to escape from their gaping mouths. The researchers thought that the clue to this behaviour lay in the frog’s poison glands, as frogs with purged glands did not induce these behaviours and rarely escaped from the jaws of the snakes.
Several compounds in the frog’s poison glands are known to have neuroleptic (prescription medication that blocks dopamine receptors in the brain) properties, which have been previously linked to causing muscle movements in the mouth and face of medication-takers.
The African clawed frog has been used extensively in laboratory research, particularly in biomedical research and regenerative medical research – notably for its ability to regenerate tissue, organs and limbs. In fact, the frog was the first vertebrate to be cloned in a laboratory. Its skin also produces an antibiotic that rapidly heals wounds.
The frog’s popularity in research has led to it becoming an invasive species, as it’s thought that they have spread after escaping from laboratories and hospitals. Its native environment is the Great Rift Valley in East Africa, although it’s now found in freshwater areas all over the world.
