1997: Dolly the sheep revealed to the press
Dolly the Sheep, the first successfully cloned mammal, was revealed to the press on 5 July 1997.
She was cloned from a cell taken from a mammary gland of a six-year-old Finn Dorset sheep and an egg cell taken from a Scottish Blackface sheep.
Cloning Dolly opened up possibilities for medical and agricultural advances for humans but also raised important questions about cloning and ethics.
成人快手 Archive: Originally broadcast on 5 July 1997.