"There were several monitors, all running so fast it was hard to see what they were showing. Wu pushed a button and slowed one image. "Here you see the actual structure of a small fragment of dinosaur DNA," Wu said. "Notice the sequence is made up of four basic compounds--adenine, thymine, guanine, and cytosine. This amount of DNA probably contains instructions to make a single protein--say, a hormone or an enzyme. The full DNA molecule contains three billion of these bases. If we looked at a screen like this once a second, for eight hours a day, it'd still take more than two years to look at the entire DNA strand. It's that big."