Shapiro and Green at the forefront of a relatively new field of study called ancient DNA—the ancient being something of a misnomer because it can refer to DNA samples that are “only” 100 or so years old. What makes the DNA “ancient” is that comes from samples that have degraded in some way. This means that the challenge for people like Shapiro and Green is not just to find samples and extract DNA, but also to differentiate what DNA belongs to the organism itself from DNA from whatever might have colonized it in the years since its death, and then to figure out which parts of the recovered DNA might be damaged. Not to mention figuring out what all of the information means.
“If modern DNA is like a party streamer,” Shapiro says, “what we work with is the equivalent of confetti found in the gutter the day after a parade.” Further complicating the challenge: in some cases the DNA that truly matters to the researchers makes up less than 1% of the DNA that is recovered.
But thanks to new technologies barely a decade old that make it possible to do low-cost, high-volume DNA sequencing, Shapiro and Green can now answer questions about evolution we’ve never been able to answer before
-Beth Shapiro, PhD, Associate Professor, Ecology and Evolutionary Biology, UC Santa Cruz