In 2000, French scientists spliced crystal jellyfish protein into a white rabbit's genome and the rabbit later glowed under black lights. Animal rights groups were quick to protest any further experimentation with jellyfish protein in animals. However, the crystal jellyfish, Aequorea victoria, was originally used to help study diseases like cancer and Alzheimer's. The jellyfish's green fluorescent protein was used to illuminate invisible processes that were once unable to be studied within a cell. This enlightening discovery won the 2008 Nobel Prize in Chemistry.
While the name might imply the opposite, jellyfish are not a type of fish but are invertebrate, cousins of sea anemones and coral.
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I am curious; what harm came to the rabbit?