There is a limit on how many times a mammal can be cloned before suffering ※mutational meltdown,§ Japanese scientists have discovered, after making 1,200 clones over two decades that started off with a single mouse.

The 58th generation of mice did not survive, establishing for the first time that mammals cannot be cloned an infinite number of times, the scientists said in a study published last month.

It had been hoped that this method, which involves making clones of other clones, might have a range of uses in the future, including saving endangered species or mass-producing animals for their meat.