In the past few billion years since our planet existed, many different kinds of animals have become extinct. This is still happening today, at an alarming rate. Some people say that by 2100, around half of the species that are alive today will be completely extinct. However, a remarkable recent scientific discovery may help us save these species, and may even bring some that were long extinct back to life!

Earlier this month, Japanese scientists at the Centre for Developmental Biology in Kobe announced that they had successfully cloned two cute little mice. This is no big news - scientists have been able to clone animals for a long time now. The amazing thing is that these mice were cloned from animals which had been kept frozen, at minus 20 degrees, for around 16 years!

Of course, this does not mean we are going to see dinosaurs roaming around in parks in the near future. Scientists were quick to point out that the cloned mice had been kept safe in a laboratory, in ideal conditions. Although frozen remains of extinct animals like the woolly mammoth have been found, they have been damaged severely and may not be suitable for cloning.