His team was interested in the paleogenomics of the cave bear, a species that disappeared over 15,000 years ago. In this film, viewers can follow the in-vitro process used to extract and reproduce the cave bear's DNA. It took the researchers two years to reconstruct its entire mitochondrial genome. By comparing this genome with that of modern day bears, they managed to show that their last common ancestor lived about 1.6 million years ago. A first in the field that opens up hitherto unimaginable prospects in genetics.