Category Archives: JAPAN

Dental Tartar Yields Food Data from Japan’s Edo Period

Dental Tartar Yields Food Data from Japan’s Edo Period

Rikai Sawafuji of the University of the Ryukyus, Shintaroh Ueda of the University of Tokyo, and their colleagues analyzed samples of tartar from the teeth of 13 people who were buried in what is now eastern Tokyo in the latter half of the Edo Period, from A.D. 1603 to 1867. DNA from the rice was identified in the tartar of eight of the individuals. The DNA of other foods, including daikon radish, the minty herb “shiso” perilla, green onion, Japanese chestnut, carrot, and the pumpkin was also identified. 

A tartar formation found on teeth (Provided by Rikai Sawafuji)

However, the scientists from the University of the Ryukyus, the University of Tokyo, and elsewhere identified even the families and genera of plants eaten at the time by surveying calculus on the teeth of human remains.

The findings, expected to shed light on the dietary and other habits of people of the time, were published in the academic journal Plos One. The team of scientists sampled the DNA from teeth on the bones of 13 people unearthed in Tokyo’s Koto Ward that date to the latter half of the Edo Period.

The researchers studied what plant the samples are from, as recent research has revealed tartar contains the DNA of what was consumed by the individuals. According to the team’s findings, rice-derived DNA was detected from calculus specimens of eight people, while DNA highly likely connected to such plants as the daikon radish, “shiso” perilla, Welsh onion, Japanese chestnut, carrot and pumpkin from nine genera in seven families were also discovered.

Those plants are, according to the scientists, described as foods in records from the period. Meanwhile, DNA from the tobacco genus was identified as well, reinforcing the theory that smoking had already become a popular practice by that time.

A Dipterocarpaceae-linked DNA sample, which is typically found in the tropics, indicates that the resin of the plant was used as an ingredient for tooth powder in the Edo Period, the scientists said.

Team members included Rikai Sawafuji from the University of the Ryukyus, a research fellow affiliated with the Japan Society for the Promotion of Science who now belongs to the Graduate University for Advanced Studies; and Shintaro Ueda, a professor emeritus of bioscience at the University of Tokyo. 

Sawafuji expressed high expectations for the possibility of the DNA analysis allowing researchers in the future to determine even people’s personal favorites based on the remnants left behind on their teeth.

“The technique will make it possible to survey what each individual ate,” said Sawafuji.

Another anticipated benefit of the method is that how plants were used, including the staple foods of each era, which can be determined, because “plants detected from the teeth of many people’s remains were likely widely consumed.”

Tartar as Research Specimen

In the past, calculus formations remaining in human skulls were often simply removed, since their presence made it difficult to examine the shapes of teeth and other factors.

But DNA, starch particles, proteins, and other substances contained in tartar can currently be surveyed in detail, adding to calculus’ significance for research purposes.

Among other ways to take advantage of tartar, the DNA analysis was introduced 10 or so years ago, although more than 99 percent of DNA detected from the object come from bacilli and the method was first adopted to research changing bacterial floras in the oral cavity.

In the early stage of the development, a study was carried out in 2014 to collect DNA from pork and wheat ingested by Germans in the medieval period.

In 2017, the results of the analysis of calculus from Neanderthal men dating to 50,000 years ago were released, showing they ate different foodstuffs in different regions because DNA from mutton and other kinds of meat, as well as moss and mushrooms, were found.

As the poplar-derived DNA was also discovered, speculation swirled that the plant, currently used for making aspirin, “could be used to ease the pain.”

Hiroki Ota, a bioscience professor at the University of Tokyo, noted, however, that the DNA-based method should be combined with various other techniques for improved research.

“Tartar DNA no doubt reflects what the person ate, so use of the substance will spread further,” said Ota. “But calculus could be formed differently in differing dietary cultures. So the research accuracy needs to be improved by conducting a variety of methods using coprolites (fossilized feces) and other objects to uncover all details.”

Massive Stones Unearthed in Shogun’s Garden in Central Japan

Massive Stones Unearthed in Shogun’s Garden in Central Japan

Eight massive stones, including one that weighs nearly ten tons, have been unearthed in the garden at Muromachi-dono, the so-called Flower Palace built by the Ashikaga Shogunate in A.D. 1381. 

A massive stone is unearthed in the garden of the former residence of the Ashikaga Shogunate during the Muromachi Period (1336-1573).

The largest stone is nearly 3 meters long and one of eight, seven of which are situated around the site of a pond in the former residence of the Ashikaga Shogunate.

On April 10 the Kyoto City Center for Archeological Research announced the findings. The Kyoto site of the Kamigyo Ward is called Muromachi-dono, also known as “Hana no Gosho” (Flower Palace).

The unearthed stones, which are unusually huge compared with those found at other garden sites of ruling elites, were undoubtedly intended to show off the great power wielded by the shogun and his family, Expert Said.

In 1381 the complex was completed at the request of the Third Shogun of Ashikaga Shogunate, Ashikaga Yoshimitsu (1358-1408), and used as his and his successors’ residence and headquarters.

The site is estimated to have spanned around 7,600 tsubo, or about half the size of the massive Tokyo Dome in the capital’s Bunkyo Ward. One tsubo is equivalent to about 3.3 square meters.

The residence is also depicted in “Uesugi Rakuchu-Rakugai Zu” (Scenes in and Around the Capital), a national treasure. Kyoto in those days was the capital of Japan.

The eight stones were found in the southeastern part of the site and are deemed an especially important discovery.

They measure between 95 centimeters and 2.7 meters. Seven of them were situated close to each other.

The institute believes the stones were placed during the rule of the eighth Muromachi shogun, Ashikaga Yoshimasa (1436-1490), who also involved in constructing Kyoto’s fabulous Ginkakuji Temple (Silver Pavilion), based on an analysis of earthenware excavated from stratum in which they lay.

The residence is believed to have comprised a group of buildings in the north and a garden that centers around a pond in the south.

During the excavation, researchers also found that the pond stretched at least 45 meters north to south and about 60 meters east to west.

“Ashikaga Yoshimasa until now hadn’t been held in particularly high regard for his political skills because he triggered the Onin War (1467-1477), which was followed by the Warring States period,” said Hisao Suzuki, a professor of archaeology and history of gardens at Kyoto Sangyo University.

“This discovery shows that he excelled at fostering culture and engineering technology.”

The excavation was carried out from January through April 9 ahead of the construction of a building. 

Due to the new coronavirus outbreak, the excavation site will be backfilled, and no on-site briefing session for the public will be held.

Ancient Persian Glassware Identified in Japan

A fragment of a glass bowl unearthed on Okinoshima island came from ancient Persia during the Sassanian dynasty

Munakata, Fukuoka Prefecture — During the Sassanian dynasty (226-651), researchers confirmed that a fragment of a glass bowl discovered on Okinoshima Island, a UNESCO World Heritage site here, originated from ancient Persia.

The glass bowl fragment found on Okinoshima island.

Munakata Taisha shrine teamed up with experts and used X-ray imaging to analyze the artifact as well as small pebble-shaped “kirikodama” ornaments made of glass. They date to the late fifth century to the seventh century.

Okinoshima island, located off Munakata, Fukuoka Prefecture, is considered by the shrine to be so sacred that only males can visit and only if they engage in purification rituals before coming ashore.

The island has yielded a treasure trove of artifacts from ceremonies held there between the late fourth and ninth centuries that are believed to have been carried out during the time of the ancient Yamato kingdom.

To date, around 80,000 items unearthed are designated as national treasures.

The glass bowl fragment measures about 5.6 centimeters. It has a circular base and the surface of the bowl is scratched.

It bears the characteristics of cut glass produced during the Sassanian Empire that encompassed modern-day Iran and surrounding countries. Iraq has yielded similar examples of the glasswear.

Munakata Taisha shrine worked with a team headed by Izumi Nakai, professor emeritus of Tokyo University of Science who specializes in analytical chemistry, to examine the artifact and pebble-shaped ornaments.

As an expert in analyzing ancient glass products, Nakai subjected the materials to fluorescent X-ray analysis so as not to damage them.

The results showed that the ashes of plants were mixed with molten glass, a characteristic of Sassanian Persia glassware.

But the pebbles remain something of a mystery, as no similar examples have been found in Japan or elsewhere. However, it was assumed the ornaments were produced by reprocessing Sassanian Persia glassware.

Makiko Fukushima, the curator of Munakata Taisha Shinpokan museum, said: “We were able to gain very precious insight into where the unearthed items were created, the route used to bring them to Japan and the degree of influence of those involved in the ceremonies where such glassware was used.”

Sixteenth-Century Wall Unearthed at Japan’s Gifu Castle

Stonewall points to Japan’s oldest castle keep built by Nobunaga

This seems like another pile of rocks to the uninitiated. But stones unearthed here apparently constitute part of the oldest castle keeps ever built in Japan. The stones form part of the top section of the base of a Gifu Castle keep likely built by legendary warlord Oda Nobunaga (1534-1582).

The Gifu Castle keep is seen in the background of a statue of Oda Nobunaga in Gifu Park.
Gifu Castle 

The discovery was made last October and is regarded as significant in the study of castle building in Japan.

City officials, revealing the discovery on Jan. 7, said it is the first time researchers have identified what they believe was part of the original keep.

The hilltop castle was captured by Nobunaga during the Warring States period (late 15th to late 16th centuries).

The castle was renamed from Inabayama Castle after Nobunaga defeated its lord, Saito Tatsuoki, in 1567. He also renamed the region, then called Inokuchi, Gifu.

Luis Frois, a Portuguese missionary who visited the site two years after the takeover, wrote, “There was a gorgeous Japanese-style guest room (at the castle on the mountain),” according to the city’s education board.

A detailed image of the stone wall, including the base of the keep, is depicted in a drawing dating to the Genroku Era (1688-1704).

Stone walls of a keep are depicted in a drawing of the castle made during the Genroku Era (1688-1704) of the Edo Period (1603-1867).

However, it had been believed that most of the original wall was long gone, as the structure was torn down during reconstruction work in 1910.

The excavation work covers an area of about 1,410 square meters atop Mount Kinkasan.

Team members decided to excavate around a stone sticking diagonally out of the ground near a wall where the rebuilt structure stands. After digging out about five square meters, the members found what is believed to be the original stone wall.

An excavated stone wall in Gifu believed to have been built under Oda Nobunaga. The excavation team started digging around a stone, center, sticking diagonally out of the ground.

The section, about 1.8 meters long and 70 centimeters high, has three levels and is located above a layer at the northwestern corner that was created during the Warring States period.

The team also found a piece of stone that supports the bottom of the corner as well as areas where the stones were joined with mazumeishi pebbles to fill the gaps, matching the characteristics of walls built under Nobunaga.

In the castle drawing, a four-meter-high stone wall is depicted above the three layers of stone walls in the vicinity of the one recently discovered.

“We will continue our research to uncover all of the details,” said Mayor Masanao Shibahashi.

Hitoshi Nakai, a professor of history of castle building in Japan at the University of Shiga Prefecture, said the discovery will shed light on the history of castle building, particularly how feudal-era keeps originated.

Nakai added that similar techniques were used for building stone walls at Azuchi Castle, and noted that the same might be true for Sakamoto Castle, where a subordinate of Nobunaga, warlord Akechi Mitsuhide (1528-1582), resided.