undersides warning predators of their toxicity. The toxin is secreted through the skin mostly from the hind legs, and sometimes the belly, in a milky substance when the frog is disturbed or frightened. When producing this substance, the frogs may also lie on their backs to show the color of their bellies, indicating their potential danger, holding up their limbs and arching their heads. This does not always work, and in addition to predation by birds and mammals, grass snakes and other water dwelling snakes are known to the consume the toads without any ill effect. Research Bombesin The skin of Oriental fire-bellied toads contains bombesin, a peptide first isolated from their relatives, European fire-bellied toads (and later other types of frogs, in the genera Rana and Phyllomedusa). Among other effects, bombesin hinders gastric functions in mammals, including dogs, cats, rabbits, and rodents. Later studies on B. orientalis discovered that the peptide came in three separate forms. Intelligence Oriental fire-bellied toads are rapid learners, especially compared to other frogs. In an experiment, slightly dehydrated toads were found able solve both simple and more complex mazes using water as a reinforcement, unlike other types of frogs (members of Rana, Bufo, and Hyla simply either did not try or leapt around aimlessly). In a simple T-maze, with their target on the right side, 80% had navigated their way successfully in only three days, with 100% having finished after four days. The left side proved more challenging, with 80% finished in three days, but the rest not done until day eight. As a model organism As common amphibians, B. orientalis make excellent model organisms for studying the effects of pollution and toxic chemicals on local environments. Studies involving them having demonstrated the harmful effects of carbaryl (which include bent trunks, thicker-set bodies, bent tails, and ventral blistering) and nonylphenol (which significantly decreased overall survival rates) on amphibian embryonic development. Conservation status The oriental fire-bellied toad was listed as least concern species by the International Union for Conservation of Nature with little threat of extinction, although the population is declining, but not at a significant rate. They occur in many protected areas in China and the Koreas, as well as six Russian nature reserves. The population in the Russian part of their range may be more threatened than others. Dangers include pollution, urbanization, and use in traditional Chinese medicine. In captivity Bombina orientalis are