On the horizon: news from the frontiers of science

Why did the chicken cross the Pacific? Florida drought uncovers archaeological treasures; and planning a voyage to a deep, deep lake.

June 7, 2007

Why did the chicken cross the ocean?

Scientists have unearthed the first concrete evidence of a Polynesian presence in South America before the European arrival. The evidence isn't pottery shards, stone tools, or boats, but ... chicken bones.

Researcher Alice Storey, lead author of the study, which appears in the current edition of the Proceedings of the National Academy of Sciences, carbon-dated 50 chicken bones found on Chile's Arauco Peninsula. The chickens died between AD 1321 and 1407, at least 85 years before Columbus made landfall in the Bahamas. Analysis revealed a genetic match with chicken bones from the same period found in American Samoa.

Humans first domesticated chickens in Southeast Asia. Polynesians brought chickens, which began appearing 3,000 years ago in their archaeological record, as well as pigs, rats, and dogs as they colonized the islands of the South Pacific. By AD 1200, Polynesians had arrived on Easter Island, 2,237 miles west of Chile.

Polynesian contact with South America would explain several enduring mysteries. Polynesians grow a sweet potato and gourd of South American origin, and when Spain's Francisco Pizarro arrived in Incan lands in 1532, he found that chickens were an integral part of Incan society.

In 1947, Thor Heyerdahl famously sailed Kon-Tiki, a balsa-wood raft, from Peru to the Tuamotu Islands. He sought to prove that Stone-Age seafarers could have colonized Easter Island from the east. "He had it backwards," Ms. Storey, a PhD candidate at the University of Auckland, told Reuters. More likely, Polynesians sailing from west to east landed on South American shores, bringing chickens and taking sweet potatoes.

Drought uncovers artifacts

A drought in Florida has reduced Lake Okeechobee to its lowest levels since record keeping began in 1932. The second-largest freshwater body in the continental United States after Lake Michigan, the lake has lost so much water that, in some places, a mile and a half of lake bed is exposed, the Associated Press reported June 4. While that's bad news for those who rely on it for water, the receding lake has given up several interesting archaeological finds, including native American pottery and bones estimated to be 500 to 1,000 years old, and maybe older.

"It looks like it's part of one of the American Indian settlements that were there – people that were intentionally interred at some point," Ryan Wheeler, the Florida state archaeologist, told the AP.

The receding water has also revealed several boats, reports the AP, including a steam-powered dredge; a motorized, wooden canoe; and a fishing boat from the 1900s rigged with a single-cylinder engine.

Voyage to the lakes beneath

In the past decade, scientists have found a network of large lakes and rivers beneath the Antarctic ice sheet. Now, a lead expert in these subglacial lakes says we are three to five years away from visiting them.

Mahlon "Chuck" Kennicutt II, a Texas A&M University professor of oceanography and a director of the Subglacial Antarctic Lake Environments office, says the estimated 145 lakes beneath the ice may host a range of life forms found nowhere else. The lakes are important for regulating both the Antarctic ice flow and world climate, and sediment from their floors could reveal much about earth's past climate.

Lake Vostok, a Lake Ontario-sized body of water under 2-1/2 miles of ice, should be the first destination, Professor Kennicutt says. But the technology required to conduct such a voyage – which would also require sterilizing all equipment to avoid contaminating the lakes – doesn't exist yet.