This was a very interesting article. How do they know that the DNA is from the specific animals mentioned, especially the extinct ones?

Beau T. Jarvis
Tustin, Calif.

The scientists compared the DNA they found with the genetic sequences described in GenBank, a repository of genetic information compiled by the National Institutes of Health in Bethesda, Md. The DNA from the 38 extinct animals and plants in that 130,000-organism database came from the fossils of species as diverse as dodos that lived until the 1600s, mammoths that lived during the last Ice Age, and beetles that were trapped in amber more than 120 million years ago .–S. Perkins