Just as some plants have developed toxic chemicals to defend predators, corals have also evolved to produce chemical toxins as well. Gorgonian coral, as they are commonly known, produces a toxin that when eaten, expels it inside the predator. Although this can prevent most predators of the reef, some have co-evolved with the coral, and can withstand their toxins.
Cyphoma gibbosum, a sea snail of the tropical Caribbean, makes its diet of the toxic gorgonian coral. This small sea snail is the number one predator of the coral. But how can the C. gibbosum eat through the toxic tissue of the coral and not be inflicted or detoured in any way? To not be affected by the toxins, the snails have to filter out the harmful chemicals, just as a human liver does. The digestive glands of the sea snail have been evolving and fine tuning to be able to cope with the gorgonians toxins. The detoxification genes of the sea snail are much more prevalent so they can rid the dangerous chemicals. These genes code for enzymes to metabolize the chemicals quicker, make them water soluble, and secrete them from the cell. Another enzyme can mark the harmful chemical, and signal the cell to secrete it through the cell membrane. Both of the enzymes and detoxifying techniques allow the C. gibbosum to digest and eat the gorgonian coral. With co-evolution, the sea snail can successfully make its diet on a toxic food source.