Masaki Eda

Poultry are farmed globally, with chicken (Gallus gallus domesticus) being the leading domesticated species. Although domestic chicken bones have been reported from some Early Holocene sites, their origin is controversial and there is no reliable domestic chicken bone older than the Middle Holocene. Here, we studied goose bones from Tianluoshan—a 7,000-y-old rice cultivation village in the lower Yangtze River valley, China—using histological, geochemical, biochemical, and morphological approache

Although the tandem duplication of mitochondrial (mt) sequences, especially those of the control region (CR), has been detected in metazoan species, few studies have focused on the features of the duplicated sequence itself, such as the gene conversion rate, distribution patterns of the variation, and relative rates of evolution between the copies. To investigate the features of duplicated mt sequences, we partially sequenced the mt genome of 16 Phoebastria albatrosses belonging to three species

The Black-footed Albatross Diomedea nigripes is an endangered seabird that is endemic to the North Pacific. The genetic structure of Black-footed Albatross populations on three of the Hawaiian Islands and on Izu-Torishima Island, Japan, has been studied previously, using the mitochondrial cytochrome b region. Hawaiian and Japanese breeding groups are genetically different, and the genetic diversity of the birds on Izu-Torishima is lower than that of birds in the Hawaiian Islands. We analyzed 50

Assortative mating is an important pre‐mating isolation mechanism that has been observed in some wild populations of seabirds. The Short‐tailed Albatross Phoebastria albatrus is a globally Vulnerable seabird that breeds mainly on Torishima and the Senkaku Islands in the north‐western Pacific Ocean. Our previous studies suggested that two genetically distinct populations exist, one on Torishima and the other on the Senkaku Islands. Recently, however, several un‐ringed birds in subadult plumage ha

The ideal indicator of domestic individuals is the presence of traits that must appear in the first generation of the domestic lineage. Most wild geese are migratory, breeding in the subarctic zone and wintering in the temperate zone. If goose remains from archaeological sites in a non-breeding region are from individuals shown to have died during the breeding season, the bones are likely to be from domestic birds. Medullary bone is secondary woven bony tissue formed in the marrow cavity of bree

Many albatross remains have been found in the Japanese Islands and the surrounding areas, such as Sakhalin and South Korea. These remains are interesting for two reasons: numerous sites from which albatross remains have been found are located in coastal regions of the Far East where no albatrosses have been distributed recently, and there are some sites in which albatross remains represent a large portion of avian remains, although albatrosses are not easily preyed upon by human beings. We colle

アホウドリ Diomedea albatrus は伊豆諸島の鳥島と尖閣諸島の南小島や北小島で繁殖する危急種の海鳥である。1979年以降，鳥島で生まれたほとんどの個体が両脚に標識をされているにもかかわらず，1996年以降，鳥島の初寝崎において未標識の1個体が観察されている。2005年度の繁殖期まで，アホウドリ誘致用に設置された特定のデコイのそばに毎年巣をつくったこの鳥は，デコイにちなんで「デコちゃん」と呼ばれている。若鳥のうちに標識が両脚から外れることは考えにくいため，この鳥は尖閣諸島で生まれた個体であると考えられてきた。近年の私たちのミトコンドリアDNAの制御領域2を用いた研究によって，アホウドリには2つの系統的に離れた集団（クレード1とクレード2）が含まれていたこと，尖閣諸島で採集された資料はクレード2の個体からなること，鳥島で生まれた個体の多くがクレード1に属することが示唆されている。この鳥の巣で羽毛を採取して解析した結果，この鳥の制御領域2の配列は，これまでに知られていた配列とは異なるものの，クレード2に属することが明らかになった。このことは，デコちゃんの出生地が鳥島ではなく，尖

The chicken ( Gallus gallus domesticus ) is the most conventional domestic animal whose main ancestor is the red junglefowl, found in Southeastern Asia and the southern part of China. Chickens were believed to have been brought to the Japanese Archipelago through the Korean Peninsula during the Yayoi period, but its exact age is unknown. Based on the sexual dimorphism of morphology, we pointed out that most chickens in the Yayoi period were males and that they were rarely bred in Japanese Archip

アホウドリPhoebastria albatrusは北太平洋西部の2つの島嶼域で繁殖する危急種の海鳥である．2006～2007年度の繁殖期の個体数は約2,360羽で，約80％の個体が伊豆諸島の鳥島で，残りの約20％が尖閣諸島の南小島と北小島で繁殖する．本種は暗黙のうちに1つの保全・管理ユニットとみなされており，国際的な保護管理プロジェクトでもその集団構造には関心が払われてこなかった．しかし，これまでの研究から，約1,000年前のアホウドリに遺伝的に大きく離れた2つの集団があったことが明らかになった．19世紀後半以降の繁殖地での乱獲によって個体数と繁殖地数が大きく減少した一方，2つの集団の子孫はそれぞれ主に鳥島と尖閣諸島で繁殖していることが示唆された．現在鳥島では両集団に由来する個体が同所的に繁殖しているものの，鳥島で両集団が交雑しているのかはよくわかっていない．鳥島と尖閣諸島に生息する個体群はミトコンドリアDNAのハプロタイプ頻度が明らかに異なっていることから，それぞれの個体群は異なる管理の単位（MU）とみなしうる．尖閣諸島から鳥島への分散傾向は繁殖地での過狩猟によって強まった可能性も