Audio News for July 21st to July 27th, 2003
Welcome to the Audio News from Archaeologica! I'm Laura Pettigrew and these are the headlines in archaeological and historical news from July 21st to July 27th .
Researchers attempt to use DNA analysis on parchments
Our first story is from England, where Cambridge scientists plan to study DNA in parchments prepared from animal skins to trace where they came from. Genetic fingerprinting might soon clear up many ancient mysteries about the origins of medieval parchments. The technique may even resolve the controversy over the birthplace of the Canterbury Gospels, which are believed to have been brought to Britain around A.D. 597. Researchers will begin by hunting for ways to take tiny samples of tissue from the animal skin parchment such manuscripts are written on. This is an advance in literary research that combines both the concepts and the techniques of two seemingly unrelated disciplines: philology (fill-AWL-uh-gee), which studies how language and literature evolves, and genetics, which traces biological change. Geneticists study changes in genes among related creatures to build up an evolutionary tree and identify a likely ancestor. When it replicates, a cell copies its genes – making occasional mistakes, and then passing them along. The mutations in genes help identify descendants of the same original parent. Genetic reproduction can be compared to how medieval scribes, who were monks working long hours in Europe's monasteries, produced new copies of texts. They painstakingly copied one document from another, word by word and sentence by sentence. Because of the hand copying process, occasional mistakes were made, and then recopied by later generations of monks. The language mistakes, like genetic mutations, are passed down through generations of manuscripts and make up families of documents bearing the same errors, descended from the same ancestor. A century before the discovery of DNA, language experts already knew that a systematic study of manuscript mutations can solve questions of origins. This linguistic technique has been used to verify the earliest versions of the sections of Chaucer’s (CHOSS-er’s) Canterbury Tales, and is enormously important in Biblical studies. But now, the combination of literary and genetic research has taken a leap, from analysis of words to the analysis of the parchment. This presents new challenges. Researchers have so far been able to extract DNA from modern parchment. England still manufactures parchment to use for legal texts and the Queen's speech at the opening of parliament. The current research will try to determine how to sample the DNA of fragile ancient parchments in ways that allow for genetic analysis and comparison without damage to the priceless documents.
Ocean excavation explores Henry VIII warship
An excavation has been launched at the site of the Mary Rose, a sunken Renaissance era ship. The work could uncover new secrets about the famous warship from the reign of England’s King Henry VIII. The archaeological dives form part of a survey in advance of plans to regenerate Portsmouth naval base. The current route into the naval base is not deep enough for the new super-carriers and the navy is planning to dredge a new approach into the harbor. The navy's preferred route crosses the wreck site of the Mary Rose. The dives now underway are primarily a clearing operation prior to a full archaeological and environmental survey. The chief executive of the Mary Rose Trust, which raised the hull in 1982, said the dives would enable them to excavate important parts of the ship which have remained buried since then.
Bulgarian and US archaeologists partner in Black Sea project
In Bulgaria, local researchers will be joined by US scientists to study an ancient ship with a cargo of amphorae on the bed of the Black Sea off the coastal city of Varna (VAR-na). The government is expected to issue a license for two years of underwater work. The main goal of the Black Sea project is geological research, but it is paired by archeological expeditions that hope to discover submerged prehistoric, antique or mediaeval settlements and ships. Under the project, the Archeological Institute in Sofia (SAH-fee-ah) will partner with the American Institute of Archaeological Oceanography and Institute of Exploration of the Sea Research Foundation. Scientists from the two nations have agreed that the conservation and restoration of their archeological finds will be carried out in Bulgaria, in the scientific labs of the Bulgarian Academy of Science or others suggested by the US researchers. All will work together to prepare the final monograph reporting the research. It has been agreed that the paper is to appear no later than five years after the end of the underwater work. The Bulgarian government has stipulated that all archeological finds produced by the joint research are the property of the Republic of Bulgaria and will remain in the country.
New World genealogy loses 12,000 years
In our final story, we return to DNA and origin studies. Recently completed analysis of the genetic signatures of Siberians and American Indians scientists has provided evidence that the first human migrations to the New World from Siberia probably occurred no earlier than 18,000 years ago. The new theory chips away at arguments for migration as far back as 30,000 years ago, but reinforces archaeological findings, as well as a linguistic theory that most American languages belong to a single family called Amerind. By studying the DNA of living Siberian and American Indian populations, geneticists had previously been able to see traces of at least two early migrations from Siberia. But it has been hard to put a date on when the first people set foot in the Americas, for lack of a suitable marker in the chromosomes. A team of geneticists has now detected a change in the DNA sequence of Siberian men's Y chromosomes that took place just before the first of the two migrations into the Americas. They estimate that the DNA change occurred 15,000 to 18,000 years ago, meaning that it is after that date that the Americas must first have been occupied. The DNA change is not in a gene and makes no known difference to the men who carry it. The migration from Siberia was probably made by land, because at that time the world's sea level was much lower and a land bridge, known as Beringia, stretched across what is now the Bering Strait between Siberia and Alaska. Beringia sank beneath the waves some 11,000 years ago as the glaciers of the last ice age melted and raised the level of the sea. The second, later, migration that is also seen by the geneticists seems to have occurred some 8,000 years ago. Presumably, it was a migration by boat, given that the land bridge had long since vanished.
The date based on the new DNA marker is important because it sets an earliest limit on the colonization of America, something that archaeologists find hard to do because they cannot be sure there are not sites they may have missed. For most of the last century, the peopling of America has been seen as a story of migratory hunters trekking across the Bering land bridge in the last ice age, spreading across North America and within 1,000 years or so reaching the tip of South America. Those who left the most durable traces, fluted projectile points, were the Clovis people, named for the town in New Mexico where their artifacts were first uncovered.
That wraps up the news for this week!
For more stories and daily news updates, visit Archaeologica on the World Wide Web at www.archaeologica.org , where all the news is history!I'm Laura Pettigrew and I'll see you next week!