New insight on the formation of East Asian flora

Wu & Wu (1996) first proposed the former "Eastern Asiatic region" to be an independent floristic Kingdom, the "East Asiatic Floristic Kingdom". It is significant to the definition of the Floristic regions of the world. However, there are still some questions need to be discussed.

These are floristic regions of the Eastern Asiatic Floristic Kingdom and its two subkingdoms (A & B) based
on Wu and Wu (1996) (7). White dashed lines (A) demarcate boundaries of two floristic subkingdoms;
Photos of living plants (B) are the representatives of each subkingdom; (a) Gentiana, (b) Corydalis,
(c) Primula, (d) Pedicularis, (e) Rhodiola, (f) Saxifraga, (g) Rhododendron, (h) Eucommia,
(i) Cercidiphyllum, (j) Ginkgo, (k) Trochodendron, (l) Cathaya, (m) Davidia, (n) Metasequoia
[Credit: © Science China Press]

As many living fossil plants (Cenozoic plant relicts) only occurred in East Asian today, many researchers have suggested that the East Asiatic Floristic is an ancient flora and the cradle of North American, European floras and even the modern Paleo-tropical flora .

In addition, East Asia has also been considered to be the diversification or origin center of angiosperms. Besides this, as most paleoendemic taxa of the East Asiatic Floristic occurred in the Sino-Japanese flora and neoendemic taxa were concentrated in the Sino-Himalayan flora. Previous studies suggested that the Sino-Japanese flora is older than the Sino-Himalayan flora. Are these hypothesis true or not? However, until today these questions have not been solved well, due to the limitation of research methods and materials.

On the basis of previous studies, Prof. Sun Hang's Group from Kunming Institute of Botany, Chinese Academy of Sciences (KIB/CAS), propose the term "Metasequoia Flora" to represent the core area of the Sino-Japanese Flora. Since the living fossil plant Metasequoia glyptostroboides is one representative of the relicts or living fossil lineages that are found in this area. Similarly, They propose the term "Rhododendron Flora" to better represent the core region of the Sino-Himalayan flora, as Rhododendron is the largest genus and formed a diversity center in this region, plus it is a representative plant of the flora in this area.

These are geographical origins of the East Asian flora. Pie chart illustrate the percent of taxa originated in situ,
ambiguous origin and immigrants from other flora. Arrows indicate the biogeographical origin of East Asian
elements from other region. Photos of living plants are the representatives of different geographical origins;
 (a) Cyananthus, (b) Cotinus, (c) Rhodiola, (d) Ilex, (e) Stachyuraceae, (f) Hamamelis, (g) Coriaria,
(h) Helleborus, (i) Mandragora, (j) Cissus, (k) Hypericum, (l) Viburnum, (m) Musa, (n) Alangium,
(o) Myriophyllum, (p) Disporum, (q) Carya, (r) Schima, (s) Rhus, (t) Adenocaulon, (u) Smilax,
 (v) Diapensia, (w) Cassiope [Credit: © Science China Press]

On the basis above, the group first synthesized published molecular phylogenetic data as well as fossil information on the seed plants, try to trace the temporal and spatial evolution of East Asian flora by integrating these datasets with paleo environmental studies that are related to this area.

The results suggest that the East Asian might be relatively young, with most of its clades originating since the Miocene, it should be the refugia for ancient relict plants rather than the birthplace. The Rhododendron Flora and the Metasequoia Flora are probably of a similar age.

The formation and development of the Asian monsoon might have been the main factors that drive the evolution of East Asian flora. The unequal distribution of species diversity in Rhododendron and Metasequoia flora may be due to the diverse and heterogeneous topography and climate of this region caused by the uplift of Qinghai-Tibetan Plateau. Meanwhile, this phenomenon may be also correlated with the direction of mountains ranges in these regions. The East Asian flora appears to have multiple biogeographical origins, being closely affiliations not only with other floras in the Northern Hemisphere, but also with Gondwanan floras.

The study results are published in National Science Review.

Source: Science China Press [February 27, 2018]

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7th-century Japan site yields traces of grand banquet hall for nobility

Researchers found evidence of an oblong structure from the Asuka Period (592-710) that was likely part of a banquet hall complex for the nobility described in an eighth century official history of Japan.

The pits in the ground suggest the ancient structure in Asuka, Nara Prefecture,
measured at least 19.2 meters west to east [Credit: Yoshinori Mizuno]

The building dates from when Asuka served as the nation's capital, and its existence was announced by the education board of the Asuka village government on Feb. 21.

Researchers uncovered pits in the ground for 16 wooden pillars in the Asukadera Seiho site, which lies west of the old Asukadera temple. The pits were uncovered in the northwest part of the archaeological site and are believed to date from the seventh century.

The pits measure between 90 centimeters and 135 cm across. The placement of the pillars suggests the banquet hall measured at least 19.2 meters west to east and 4.8 meters south to north.

The old Asukadera temple is thought to have been the first Buddhist temple founded in Japan. The area west of the temple is considered to be the site of “Tsukinoki no Hiroba,” or famed square of zelkova trees mentioned in “Nihon Shoki” (The Chronicles of Japan), completed in the eighth century.

The book describes banquets held in the square in the latter half of the seventh century for people invited from the outskirts of the kingdom, including the Emishi from today’s Tohoku region and the Hayato from the southern Kyushu region.

Kanekatsu Inokuma, professor emeritus of archeology at Kyoto Tachibana University, believes “the square was a functional venue for various rituals,” adding that the discovery ties in with historical accounts of banquets hosted for the Emishi and Hayato people, with sumo tournaments put on for entertainment.

"Just how they are described in Nihon Shoki,” he said.

Tsukinoki no Hiroba is reputed to be where the young Emperor Tenji as crown prince first became acquainted with Nakatomi no Kamatari through a “kemari” ball-kicking game. They connived to stage a coup in 645 that brought about the Taika Reforms to cement the power of the imperial court.

About 300 meters north of the Asukadera Seiho site lie the Ishigami archaeological ruins, which yielded a stone figure, probably a fountain.

The Ishigami site bears traces of a facility that was enclosed by a narrow corridor-like building, which is believed to have been part of a much larger banquet complex.

Author: Yuya Tanaka | Source: The Asahi Shimbun [February 23, 2018]

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Ancient tomb containing 'splendid armour' found in Japan

Workers paving a farm road here stumbled on a 1,500-year-old underground tomb containing a large stone coffin, human remains and armor in remarkable condition.

A cuirass known as a “tanko” and preserved in excellent condition, and a stone coffin, left, have been unearthed
in Shibushi, Kagoshima Prefecture [Credit: Shibushi City Education Board]

The remains are likely of a local chieftain while the cuirass, a type of breastplate known as “tanko,” is believed to have been a gift from the Yamato imperial court in current Nara Prefecture in appreciation of the leader’s cooperation, the education board of Shibushi city said Jan. 24.

The tunnel-tomb was unearthed during farm road paving work in December.

“It was likely built for a powerful leader in the local region who was directly connected with the Yamato imperial court,” said Tatsuya Hashimoto, a professor of archaeology at the Kagoshima University Museum.

The grave, which is from the Kofun Period (late third to seventh centuries), is one of the largest tunnel-tombs in the Osumi region in eastern Kagoshima Prefecture. It boasts a vertical shaft that is 2.6 meters long, 1.8 meters wide and 1.6 meters deep. The burial chamber is 2.6 meters long, 1.9 meters wide and 90 centimeters high.

This type of construction is unique to the southern Kyushu region. The site has been named the No. 3 Harada Chikashiki Yokoanabo (Harada underground tunnel-tomb).

The skeletal remains are those of a 170-centimeter-tall adult male.

A sword, its scabbard and other items were also found in the pumice stone coffin measuring 2.4 meters. It is 60 cm wide and 50 cm tall.

The tanko is in near-immaculate condition and was standing beside the coffin. The armor measures 35 cm by 40 cm.

More than 20 burial accessories, such as an iron arrowhead, spear and iron ax were discovered.

The tomb features more grave accessories than any other tunnel-tombs in the Osumi region, according to the education board.

Author: Koji Suohara | Source: The Asahi Shimbun [February 15, 2018]

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