When Dolly the sheep – the first cloned mammal – was born 30 years ago, she became one of the most famous animals in science history. Her arrival sparked predictions of a sci-fi future filled with cloned pets, cloned humans and even resurrected extinct animals like the woolly mammoth. But the reality of cloning has turned out to be much more complicated. Today, cloning is not a technology that can simply “copy and paste” living things. Instead, it has become one biotechnology tool among many. It