This article notes the experimentation with human-animal hybrids:

In China and Britain, scientists are creating cloned man-animal embryos using rabbit eggs and human DNA. In the Caribbean island of St. Kitts, human neural stem cells are being inserted into monkey brains. At the Mayo Clinic in Minnesota, researchers have produced pigs with hybrid pig-human blood cells, demonstrating the possibility of genetic fusion between man and the lower animals.

Is there no limit to our hubris?