SSS 2009-01-12（在线收听）

This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute.

Thousands of medieval European books survive to this day. Authors and scribes carefully handwrote the works on parchments made of animal skins. But the writers didn’t always bother to sign and date their works. So we had no way of knowing where and when most of the documents are from. Until now.

Researchers at North Carolina State University have demonstrated that they can reliably extract DNA samples from such parchments. Each manuscript offers up, they say, a wealth of genetic information, because as many as a hundred animals contributed skins for one book.

The scientists propose recording DNA data from all books for which we do have a reliable date and place of origin. These reference samples would create a DNA library of dates and locations. Then the mystery manuscripts could be compared against that DNA database.

The North Carolina investigators are presenting the technique for dating old manuscripts at the upcoming annual meeting of the Bibliographical Society of America. And they’re still working on improved techniques to harvest DNA while doing minimal damage to the original priceless parchments. A way to further illuminate those illuminating books.

Thanks for the minute for Scientific American's 60-Second Science. I'm Cynthia Graber.