Although the jackalope is an invention of the imagination, it is nevertheless connected to actual horned rabbits, which exist in nature and have for centuries been collected and studied by naturalists. When the virus that causes rabbits to grow "horns" (a keratinous carcinoma) was first genetically sequenced in 1984, oncologists were able to use that genetic information to make remarkable, field-changing advances in the development of antiviral cancer therapies. The most important of these is the human papillomavirus (HPV) vaccine, which protects against cervical and other cancers. Today, jackalopes are literally helping us cure cancer