Two monkeys have followed in the hoof steps of Dolly the Sheep and become the world's first primates to be cloned from transferred DNA.
Identical long-tailed macaques Zhong Zhong and Hua Hua were born eight and six weeks ago at a laboratory in China.
But while the success marks a breakthrough in cloning research, it also raises major ethical questions.
The scientists wanted to create genetically uniform monkeys so they can be customised for ground-breaking research into human diseases.
But some could see it as a step too far towards the eventual creation of tailor-made humans.