Blue-eyed humans have a single, common ancestor

New research shows that people with blue eyes have a single, common ancestor. A team at the University of Copenhagen have tracked down a genetic mutation which took place 6-10,000 years ago and is the cause of the eye colour of all blue-eyed humans alive on the planet today.

What is the genetic mutation
“Originally, we all had brown eyes”, said Professor Eiberg from the Department of Cellular and Molecular Medicine. “But a genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a “switch”, which literally “turned off” the ability to produce brown eyes”. The OCA2 gene codes for the so-called P protein, which is involved in the production of melanin, the pigment that gives colour to our hair, eyes and skin. The “switch”, which is located in the gene adjacent to OCA2 does not, however, turn off the gene entirely, but rather limits its action to reducing the production of melanin in the iris – effectively “diluting” brown eyes to blue. The switch’s effect on OCA2 is very specific therefore. If the OCA2 gene had been completely destroyed or turned off, human beings would be without melanin in their hair, eyes or skin colour – a condition known as albinism.

Limited genetic variation
Variation in the colour of the eyes from brown to green can all be explained by the amount of melanin in the iris, but blue-eyed individuals only have a small degree of variation in the amount of melanin in their eyes. “From this we can conclude that all blue-eyed individuals are linked to the same ancestor,” says Professor Eiberg. “They have all inherited the same switch at exactly the same spot in their DNA.” Brown-eyed individuals, by contrast, have considerable individual variation in the area of their DNA that controls melanin production.

Professor Eiberg and his team examined mitochondrial DNA and compared the eye colour of blue-eyed individuals in countries as diverse as Jordan, Denmark and Turkey. His findings are the latest in a decade of genetic research, which began in 1996, when Professor Eiberg first implicated the OCA2 gene as being responsible for eye colour.

Nature shuffles our genes
The mutation of brown eyes to blue represents neither a positive nor a negative mutation. It is one of several mutations such as hair colour, baldness, freckles and beauty spots, which neither increases nor reduces a human’s chance of survival. As Professor Eiberg says, “it simply shows that nature is constantly shuffling the human genome, creating a genetic cocktail of human chromosomes and trying out different changes as it does so.”

Polynesians: Genetic Relationship to Melanesians

The origins and current genetic relationships of Pacific Islanders have generated interest and controversy for many decades. Now, a new comprehensive genetic study of almost 1,000 individuals has revealed that Polynesians and Micronesians have almost no genetic relation to Melanesians, and that groups that live in the islands of Melanesia are remarkably diverse.

The study, “The Genetic Structure of Pacific Islanders,” is published in the January issue of PLoS Genetics (http://www.plosgenetics.org). It involved researchers from Temple, University of Maryland, Yale, Binghamton University, the Marshfield Clinic Research Foundation, Victoria University in New Zealand, Mackay Memorial Hospital in Taiwan, and the Institute for Medical Research in Papua New Guinea.

The researchers analyzed more than 800 genetic markers (highly informative microsatellites) in nearly 1,000 individuals from 41 Pacific populations, as opposed to prior small-scale mitochondrial DNA or Y chromosome studies, which had produced conflicting results.

“The first settlers of Australia, New Guinea, and the large islands just to the east arrived between 50,000 and 30,000 years ago, when Neanderthals still roamed Europe,” says Jonathan Friedlaender, professor emeritus of anthropology at Temple and the study’s lead author. “These small groups were isolated and became extremely diverse during the following tens of thousands of years. Then, a little more than 3,000 years ago, the ancestors of the Polynesians and Micronesians, with their excellent sailing outrigger canoes, appeared in the islands of Melanesia, and during the following centuries settled the islands in the vast unknown regions of the central and eastern Pacific.

“Over the last 20 years there have been many hypotheses concerning where the ancestors of the Polynesians came from in Asia, how long it took them to develop their special seafaring abilities in Island Melanesia, and how much they interacted with the native Melanesian peoples there before they commenced their remarkable Diaspora across the unexplored islands in the Pacific,” he adds.

According to Friedlaender, one scenario called the ‘fast train hypothesis,’ which is supported by the mitochondrial evidence, suggests that ancestors of the Polynesians originated in Taiwan, moved through Indonesia to Island Melanesia, and then out into the unknown islands of the Pacific without having any significant contact with the Island Melanesians along the way. A counter argument called ‘slow boat hypothesis,’ which the Y chromosome evidence supports, suggests that the ancestors of the Polynesians were primarily Melanesians, and that there was very little Asian or Taiwanese influence. A third position, called the “entangled bank hypothesis,” suggests these ancient migrations simply can’t be accurately reconstructed by looking at the genetics of today’s populations, even in the context of the available archaeological evidence.

In their paper, the researchers state that their analysis is consistent with the scenario that the ancestors of Polynesians moved through Island Melanesia relatively rapidly and only intermixed to a very modest degree with the indigenous populations there.

“Our genetic analysis establishes that the Polynesians’ and Micronesians’ closest relationships are to Taiwan Aborigines and East Asians,” says Friedlaender. “Some groups in Island Melanesia who speak languages related to Polynesian, called Austronesian or Oceanic languages, do show a small Polynesian genetic contribution, but it is very minor – never more than 20 percent.

“There clearly was a lot of cultural and language influence that occurred, but the amount of genetic exchange between the groups along the way was remarkably low,” he says. “From the genetic perspective, if the ancestral train from the Taiwan vicinity to Polynesia wasn’t an express, very few passengers climbed aboard or got off along the way."

Friedlaender adds that this study also confirms and expands their findings from previous studies about the genetic diversity of Island Melanesians—among the most genetically diverse people on the planet, showing further that their diversity is neatly organized by island, island size, topography and language families.

First Temple Seal Found in Jerusalem

A stone seal bearing the name of one of the families who acted as servants in the First Temple and then returned to Jerusalem after being exiled to Babylonia has been uncovered in an archeological excavation in Jerusalem's City of David, a prominent Israeli archeologist said Wednesday.

A crescent moon, the symbol of the chief Babylonian god Sin, appears on the top of the altar.

Under this scene are three Hebrew letters spelling Temech, Mazar said.

The 2,500-year-old black stone seal, which has the name "Temech" engraved on it, was found earlier this week amid stratified debris in the excavation under way just outside the Old City walls near the Dung Gate, said archeologist Dr. Eilat Mazar, who is leading the dig.

According to the Book of Nehemiah, the Temech family were servants of the First Temple and were sent into exile to Babylon following its destruction by the Babylonians in 586 BCE.

The family was among those who later returned to Jerusalem, the Bible recounts.

The seal, which was bought in Babylon and dates to 538-445 BCE, portrays a common and popular cultic scene, Mazar said.

The 2.1 x 1.8-cm. elliptical seal is engraved with two bearded priests standing on either side of an incense altar with their hands raised forward in a position of worship.

The Bible refers to the Temech family: "These are the children of the province, that went up out of the captivity, of those that had been carried away, whom Nebuchadnezzar the king of Babylon had carried away, and came again to Jerusalem and to Judah, every one unto his city." [Nehemiah 7:6]... "The Nethinim [7:46]"... The children of Temech." [7:55].

The fact that this cultic scene relates to the Babylonian chief god seemed not to have disturbed the Jews who used it on their own seal, she added.

The seal of one of the members of the Temech family was discovered just dozens of meters away from the Opel area, where the servants of the Temple, or "Nethinim," lived in the time of Nehemiah, Mazar said.

"The seal of the Temech family gives us a direct connection between archeology and the biblical sources and serves as actual evidence of a family mentioned in the Bible," she said. "One cannot help being astonished by the credibility of the biblical source as seen by the archaeological find."

The find will be announced by Mazar at the 8th annual Herzliya Conference on Sunday.

The archeologist, who rose to international prominence for her recent excavation that may have uncovered King David's palace, most recently uncovered the remnants of a wall from Nehemiah.

Biblical Wall May Have Been Located

A wall mentioned in the Bible's Book of Nehemiah and long sought by archaeologists apparently has been found, an Israeli archaeologist says.
A team of archaeologists discovered the wall in Jerusalem's ancient City of David during a rescue attempt on a tower that was in danger of collapse, said Eilat Mazar, head of the Institute of Archaeology at the Shalem Center, a Jerusalem-based research and educational institute, and leader of the dig.
Artifacts including pottery shards and arrowheads found under the tower suggested that both the tower and the nearby wall are from the 5th century B.C., the time of Nehemiah, Mazar said this week. Scholars previously thought the wall dated to the Hasmonean period from about 142 B.C. to 37 B.C.
The findings suggest that the structure was actually part of the same city wall the Bible says Nehemiah rebuilt, Mazar said. The Book of Nehemiah gives a detailed description of construction of the walls, destroyed earlier by the Babylonians.
"We were amazed," she said, noting that the discovery was made at a time when many scholars argued that the wall did not exist.
"This was a great surprise. It was something we didn't plan," Mazar said.
The first phase of the dig, completed in 2005, uncovered what Mazar believes to be the remains of King David's palace, built by King Hiram of Tyre, and also mentioned in the Bible.
Ephraim Stern, professor emeritus of archaeology at Hebrew University and chairman of the state of Israel archaeological council, offered support for Mazar's claim.
"The material she showed me is from the Persian period," the period of Nehemiah, he said. "I can sign on the date of the material she found."
However, another scholar disputed the significance of the discovery.
Israel Finkelstein, professor of archaeology at Tel Aviv University, called the discovery "an interesting find," but said the pottery and other artifacts do not indicate that the wall was built in the time of Nehemiah. Because the debris was not connected to a floor or other structural part of the wall, the wall could have been built later, Finkelstein said.
"The wall could have been built, theoretically, in the Ottoman period," he said. "It's not later than the pottery — that's all we know."

Rethinking Byzantine-era Judaism

A row of artisans and laborers - one with a saw in his hand, another with a chisel, and others with various sized hammers - are depicted on the mosaic floor recently uncovered in a Roman- or Byzantine-era synagogue at Khirbet Wadi Hamam, on Mount Nitai in the Lower Galilee. The workers appear next to a very large building, which they seem to be constructing.

Because the image appears on the synagogue floor, the researchers have assumed it depicts the construction of an important Biblical structure. Is it the Temple, Noah's Ark, the Tower of Babel, or some other well-known work?

Dr. Uzi Leibner of the Hebrew University's Institute of Archaeology and Scholion Interdisciplinary Research Center in Jewish Studies, who is leading the excavation, has no clear answer at this stage. What is clear is that the mosaic, constructed from very small stones - whose sides measure about four millimeters each - is unique. No such scenes have been found in other ancient synagogues or structures in Israel from that period. But which period exactly are we referring to - the Roman or the Byzantine? The dig at the synagogue is being carried out to answer that question.

To judge by the findings, the synagogue, which sits within the Arbel National Park, is a "Galilean synagogue" - a high-quality Romanesque structure with an elaborate facade facing toward Jerusalem and attractive stone carvings. Synagogues of this type were thought to date from the late Roman period, between the second and fourth centuries. However, in the last few years, researchers have discovered that synagogues of this type were built in the Byzantine era, too - between the fifth and sixth centuries.

The debate was sparked by the synagogue at Capernaum, a fine example of a Galilean synagogue that clearly was built in the fifth century. The findings from that synagogue and others led some researchers to consider the hypothesis that the Galilean synagogues were built mainly in the fifth and sixth centuries.

Contradictory evidence

On the face of it, this theory contradicts everything known about Judaism in the beginning of the first millennium C.E., and its relations with the ruling empires at the time. The common wisdom is that Jewish settlement flourished in the Galilee in the late Roman era - Rabbi Yehuda Hanassi compiled the Mishna at Zippori, and remarkable public buildings were constructed in many Jewish communities. However, from the mid-fourth century, when the Christian Byzantine empire rose to power, Jewish life was hampered, and some of the laws at that time even forbade the establishment of synagogues.

However, the archaeological findings from Capernaum and other synagogues indicate that things were more complex than historical records may indicate. More evidence now supports the theory that most of the Galilean synagogues actually were built during the Byzantine period, and that their Romanesque components were initially parts of earlier structures.

The synagogue at Khirbet Wadi Hamam was large and elaborate. It had a long hall running from north to south, of which about one quarter was exposed in the last excavation season, with a southern facade facing Jerusalem. The hall contained three rows of columns, and had two rows of benches along the northern, western and eastern walls.

The uniqueness of the building lies not only in its mosaic floor, but also in its combination of basalt and limestone. The walls were built from layers of basalt topped by layers of limestone; the stone benches incorporated limestone as well. The researchers believe the limestone was integrated into the structure during a massive repair. As in other Galilean synagogues, this one also contains late Roman-era architectural details - most of them also from limestone. However, the researchers believe that the signs of renovation could indicate the structure was actually built at a later stage, and that these items actually were part of an earlier structure.

The synagogue lies inside a large village, of more than 50 dunams, one of the larger, late Roman-era and Byzantine-era Jewish villages discovered in the rural Galilee. It is located strategically above the source of the Arbel river and the ancient road that wound from the Kinneret basin to the Lower Galilee and from there, via the Beit Netofa valley, to the Mediterranean sea.

Not far away were two large, well-known communities - Kfar Arbel and Migdal - as well as the big Jewish centers of the period, Tiberias and Zippori. Despite all these facts, the original name of the community was not preserved there, and it is still unknown. Findings indicate the village was abandoned permanently in the fourth century. Researchers are hoping to learn at what stage the synagogue, with its unique mosaic floor, was built.

Judging by other buildings unearthed close to the synagogue - an oil press and a two-story dwelling - the residents of the village were fairly well-off. The homes in the community were built on terraces along the slopes of the hill, separated by lanes. Since the village apparently was abandoned in the fourth century - which contradicts the claim that the synagogue dates to the Byzantine era - that period's architecture can be examined without interference from later structures. Leibner believes the synagogue could be a test case that would help researchers improve their dating methods for Galilean synagogues. In the upcoming excavation seasons, he says he intends to find more clues that would provide a precise date, and thus possibly solve the riddle.

Queen Helene's mansion in ancient Jerusalem

Israeli archaeologists digging in an east Jerusalem parking lot have uncovered a 2,000-year-old mansion they believe likely belonged to Queen Helene of Adiabene, a minor but exceptional character in the city's history.

The remains of the building were unearthed just outside the walls of Jerusalem's Old City, underneath layers of later settlement that were themselves hidden until recently under the asphalt of a small parking lot.

The dig site is in the Arab neighborhood of Silwan, built on a slope that houses the most ancient remnants of settlement in Jerusalem and is known to scholars as the City of David.

The building, which includes storerooms, living quarters and ritual baths, is by far the largest and most elaborate structure discovered by archaeologists in the City of David area, which was home 2,000 years ago almost exclusively to the city's poor. The contemporary Jewish historian Josephus Flavius, who penned detailed descriptions of Jerusalem, mentions only one wealthy family that lived there — the family of Queen Helene.

According to Josephus and Jewish texts, Helene was from a royal clan that ruled Adiabene, a region now in northern Iraq. Along with her family, she converted to Judaism and came to Jerusalem in the first half of the first century A.D.

Helene merited grateful mention in the Mishna, the written version of Judaism's oral tradition, where she is praised for her generosity to Jerusalem's poor and for making contributions to the Second Temple, the center of the Jewish faith, which was just a few hundred meters (yards) uphill from her house. She was buried in an elaborate tomb not far away.

Today there is a downtown Jerusalem street named for her.

There is a "high probability" that the mansion belonged to Helene's family, simply because no other building comes close to matching the historical description, Israel Antiquities Authority archaeologist Doron Ben-Ami said at a news conference announcing the discovery Wednesday.

Built when Jerusalem was capital of the Roman-ruled territory of Judea, the building was destroyed along with the temple and the rest of the city when Roman legions quelled a Jewish revolt nearly two millennia ago, he said.

Diggers at the site discerned that the massive stones of the second floor had been purposely toppled onto the arches of the first, causing the house to collapse, he said, and in the ruins they found ceramic shards and coins dating to the time of the Jewish revolt against Rome.

"This amazing structure was destroyed with the destruction of Jerusalem in 70 A.D.," Ben-Ami said.

Aren Maier, an archaeology professor at Israel's Bar-Ilan University, said Ben-Ami's hypothesis about the house's famous resident was a good one, because no similar building has yet been found anywhere nearby.

"If he did find a massive building of this kind, of course you can't say for sure, but it's certainly logical," Maier said.

Some of the most interesting archaeological finds in Jerusalem in recent years have come from the City of David dig, which has also become a popular tourist site.

But the dig is controversial, because it's largely funded by a foundation affiliated with hardline Jewish settlers that is also buying up Palestinian property in the neighborhood and moving Jewish families in.

Israel captured east Jerusalem from Jordan in the 1967 Mideast War. Palestinians see the eastern part of the city as capital of a future state.

Southwestern Indians ferment corn and make beer?

The belief among some archeologists that Europeans introduced alcohol to the Indians of the American Southwest may be faulty.

Ancient and modern pot sherds collected by New Mexico state archeologist Glenna Dean, in conjunction with analyses by Sandia National Laboratories researcher Ted Borek, open the possibility that food or beverages made from fermenting corn were consumed by native inhabitants centuries before the Spanish arrived.

Dean, researching through her small business Archeobotanical Services, says, “There’s been an artificial construct among archeologists working in New Mexico that no one had alcohol here until the Spanish brought grapes and wine. That’s so counter-intuitive. It doesn’t make sense to me as a social scientist that New Mexico would have been an island in pre-Columbian times. By this reasoning, ancestral puebloans would have been the only ones in the Southwest not to know about fermentation.”

Not only does historical evidence for fermented beverages exist for surrounding native groups, but people around the world have found ways to alter their consciousness, she says: “Wild yeast blows everywhere.” In the Middle Ages in Europe, “Everyone drank ale because the fermentation purified water.” Egyptian tombs contained loaves of bread “that we used to assume were to eat, but they’re actually dry beer: put bread in water, you get beer.”

Closer to home, the Tarahumara Indians in northern Mexico to this day drink a weak beer called tiswin, made by fermenting corn kernels.

Could ancestral puebloan farmers — whose ancient mud and rock homes have been found in New Mexico, Arizona, Utah, and Colorado — have done the same?

To check her hypothesis, Dean presented Borek with three types of samples: pots in which she herself brewed tiswin, brewing pots used by Tarahumara Indians, and pot sherds from 800-year-old settlements in west-central New Mexico. The question: would analysis support the idea that ancient farmers enhanced their nutrition — and perhaps enjoyment of foods — by manipulating wild yeast and corn mixtures centuries before Columbus?

Borek, working under a Sandia program that permits limited use of Sandia tools to aid local small businesses, used gas chromatography and mass spectrometry (rather than destructive solvents) to analyze vapors produced by mild heating of the pot samples.

Sandia is a National Nuclear Security Administration laboratory.

From Dean’s pots, Borek developed a profile of gasses emitted from a known tiswin source. Then he examined Tarahumaran pots to see whether the gaseous profiles corresponded. Finally he examined pot sherds that had been buried for centuries to see if the obviously weakened fumes would match, in kind if not in volume, his previous two samples.

Comparing peaks across the three data sets showed the presence of similar organic species, Borek says, though more work must be done before positive conclusions can be drawn.

“We see similarities. We have not found that ‘smoking gun’ that definitely provides evidence of intentional fermentation. It’s always possible that corn fermented in a pot without the intent of the owner,” he says, “and that it wasn’t meant to be drunk.”

Analysis is now underway to highlight patterns of organic species that might provide a more definite, intentional result.

“There appear to be consistencies across the modern home brew and Tarahumaran pots,” Borek says. “We are currently examining all data to look for markers that would indicate intentional fermentation occurred on archeological articles.”

The work opens new, unexpected doors, he says, for understanding the human past by means of gas chromatography and mass spectrometry.

Sandia researcher Curt Mowry is examining data and comparing all sets across the provided references, Tarahumaran pots, and ancient samples.

The results were presented by Borek in a talk at the Materials Research Society fall meeting in Boston last week.

The equipment used in this study is commercially available hardware, modified by Sandia to investigate traces of organic materials in the ambient air of the Washington DC Metro system and on weapon components and materials.