DNA is one of the most powerful substances in the universe. In the same structure it can encode the instructions to make uranium-munching microbes, giant flying lizards, or a stand of quaking aspens five miles wide. It can store every movie ever made in a single test tube. And it can stick around for tens of thousands of years. Just this week, Japanese scientists revealed they’d awakened some ancient wooly mammoth DNA by sticking it into mice embryos. What is dead may never die, indeed.