After years of fiddling with human, mouse, rabbit, and cow cells, researcher Robert Lanza has declared that it's impossible to create human-animal hybrid embryos, but that human cloning appears to be ...

Since the mid-1990s, scientists have been obsessed with cloning animals. Dolly the sheep famously became the first mammal to be cloned from a cell taken from an adult mammary gland almost 30 years ago ...