"Signs carved into 8,600-year-old tortoise shells found in China may be the earliest written words, say archaeologists.

The symbols were written down in the late Stone Age, or Neolithic Age. They predate the earliest recorded writings from Mesopotamia - in what is now Iraq - by more than 2,000 years."

Early versions of the I Ching (and therefore DNA) were also written on tortoise shells:

History of I Ching

DNA and I Ching