복숭아의 변신

A species of peach related to the 7,500-year-old pits found in China recently (left), and today's more modern versions (right).

Courtesy of Jose Chaparro/University of Florida

The modern peach is a work of art: rosy, fuzzy, fragrant, fragile — and, of course, impossibly sweet and juicy. But that enchanting fruit is the product of centuries of painstaking breeding that have transformed it from its humble origins. The peach of the past was much smaller, acidic and a greenish-cream color.

Where the original, wild peach came from has been a mystery, but a new clue brings us closer than ever to its origin.

"It's such a kind of a monkey wrench in the works," Gary Crawford, paleoethnobotanist at the University of Toronto, Mississauga and lead author of the study, tells The Salt, "Everybody's been saying western China or northern China, but now we're saying the data are coming from the lower Yangtze Valley."A recent archaeological excavation of peach pits points to the lower Yangtze River Valley in southern China as one of the first places the peach was domesticated, a studypublished in early September inPLOS onE reveals. About 7,500 years ago, farmers there began cultivating a much smaller, whiter peach than we know today. Radiocarbon dating of the pits and their location indicates that these farmers were pretty savvy about grafting and fruit reproduction. But the location of the agricultural evidence is not where scientists expected it to be.

Crawford's research examined Chinese peach pits, including their length, width and suture diameter, in addition to radiocarbon dating to conclude that the cultivation of peaches in China occurred much earlier than previously thought. Their findings indicate the domestication process took at least 3,000 years, with the most similar to modern peach stones found in the Liangzhu culture about 5,000 years ago and the least similar in the lower Yangtze Valley.

In the ensuing millennia, the peach traveled from China to Japan, India, through the Roman Empire (making an appearance on a mosaic in Herculaneum, Italy, 2,000 years ago), and finally from Europe to the New World. All along the way farmers selected for certain desirable traits, markedly shaping the peach's destiny.

China has the highest genetic diversity of peaches of any country, with 495 cultivars.

"Basically they collected and started crossing it with other varieties, and they started producing seedlings out of that," says Dario Chavez, a peach research specialist at the University of Georgia. That's how we arrived at varieties like the Elberta peach — a stereotypically good-looking peach with orange flesh and orange and red skin. "What happened with Elberta is present in all the peaches," he says.

In other words, all the varieties we have today came from something very different. We don't know exactly what the original, wild peach looked like. What we do know is that over years of domestication, the peach became red and blushed. While the peaches of yore left clean pits, they now leave fruit clinging to their centers. We also selected for firmer fruits for shipping and canning purposes.

Although they think they're close, Crawford and others want to find that first peach — before domestication. He says, "We're still trying to figure out what the wild peach actually is, what the ancestor of this peach is."