The first animal to ever become 'un-extinct' was a Pyrenean Ibex. Unfortunately it was extinct again within 7 minutes!

When a species used to become extinct, there was not much that could be done about it except put its picture and maybe some of its bones or fossils in a museum.

When the Pyrenean Ibex, a species of wild goat, became extinct in 2000, scientists decided to try and ‘de-extinct’ it.

They had some DNA from one of the last females named Celia, and they decided to attempt to clone the animal.

In January 2009, the cloned female Pyrenean Ibex was born alive and the Pyrenean ibex became the first taxon ever to become ‘un-extinct’ for a very short time. The little Ibex survived for only seven minutes before she died from lung defects. It had a extra lobe in the left lung and the lungs collapsed.

Scientists believe this happened because the DNA for the clone was taken from an aged individual. Celia was already 13 years old.

Aged DNA usually cause problems for clones and leads to a shorter lifespan. Even if the cloned Ibex survived, it would not have lived very long.

(Source)