We've only scratched the surface of the secrets hidden within the coils of DNA, but little by little, scientists are teasing out its inner workings. This episode of Today's Green Minute deals with the work of a scientist who has been able to clone mice that have been frozen for years. Previously, once a cell was frozen, its DNA was unreadable, but this work has changed all that—and the implications are staggering: by reading DNA from frozen wooly mammoth cells, we may someday bring back species that we once thought were lost forever!