{"@context":"http://iiif.io/api/presentation/4/context.json","id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/manifest","type":"Manifest","label":{"ja":["化石クジラ発掘地点 MPC 675"],"en":["Fossil whale excavation site MPC 675"]},"summary":{"ja":["セロ・バジェナ（Cerro Ballena）は、チリ北部アタカマ州のカルデラの町の近くにある特異な化石産地で、数十体の化石クジラの骨格が保存されていた。2010〜2011年のパンアメリカン・ハイウェイの拡幅工事の後、チリと米国の古生物学者たちがこの産地で40体を超える化石クジラや他の海生動物の骨格を記録した。興味深いことに、これらの化石は、産地で上下に重なり合う4つの独立した化石包含層に由来しており、この化石クジラ（MPC 675）は化石包含層BL-2から採集された。スミソニアンのデジタル化プログラム室（Digitization Program Office）は、レーザースキャンや写真測量（フォトグラメトリ）を含むさまざまな技術を用いて、セロ・バジェナの化石クジラの3Dモデルを作成した。\n\n セロ・バジェナの化石は約700万〜900万年前のもので、後期中新世として知られる地質時代に属する。チリとスミソニアンの科学者による発掘によって、この産地には多様な化石クジラの個体骨格があり、成体と幼体が完全な骨格として保存された数種の異なるクジラが含まれることが明らかになった。セロ・バジェナの化石クジラの密度は、これまで世界で知られている中で最も高い。多くの化石クジラの骨格は、頭骨と顎が脊柱（背骨）と関節した状態で保存され、時には前肢（ひれ）の骨も伴って、完存していた。科学者たちはこれらの骨格の3Dモデルを用いて、骨どうしの解剖学的なつながりの程度を評価し、骨格中の骨が生前の関節位置からどれだけ動いたかを具体的に計測した。\n\n 全体として、セロ・バジェナの化石クジラの骨格の骨には、大型動物による攪乱や食い荒らしの痕跡がほとんど見られず、これは死から埋没までの時間が短かったことを示唆している。セロ・バジェナでの地質学的調査は、これらの岩層が古代の干潟を表していることを指し示した。産地の骨格が互いに数メートルしか離れていない位置で発見されたことも、その遺骸が――おそらく波の作用によって――この場所に集積したことを示唆している。多くの骨格は腹を上にして埋没しており、クジラが干潟に到達した時点ですでに死後かなりの時間が経っていたことのさらなる証拠となっている。これらの証拠を総合すると、古代の有害な藻類の大発生（有害藻類ブルーム）が、この産地のすべての動物の死の最も有力な原因であることが示される。またそれは時代を越えて繰り返し起こりうる原因であり、4つの化石包含層それぞれにわたってセロ・バジェナにクジラや他の動物が集積したことを説明できる。\n\n 高速道路拡幅に伴う発掘は現在完了しているが、道路の切り通しの東西に広がる岩層に保存された化石は、なお数百体の骨格が近くに埋もれていることを示唆している。この産地の骨格の規模と密度は、米国のラ・ブレア・タールピットや恐竜国定記念物（ダイナソー・ナショナル・モニュメント）に匹敵するほど、この場所を特異なものにしている。\n\n 学術論文はこちら：https://royalsocietypublishing.org/doi/full/10.1098/rspb.2013.3316\n\n 産地のさらなる画像やデータについては、こちらを参照：https://www.si.edu/newsdesk/photos/cerro-ballena-fossil-whales"],"en":["Cerro Ballena is a unique fossil site near the town of Caldera, in the Atacama Region of northern Chile that preserved several dozen skeletons of fossil whales. After road expansion of the Pan­-American Highway from 2010-2011, Chilean and US paleontologists documented over 40 skeletons of fossil whales and other marine animals at this site. Interestingly, these fossils derived four separate bone-bearing levels that were layered one on top of each other at the site; this fossil whale (MPC 675) was collected on bone-bearing level BL-2. Smithsonian’s Digitization Program Office created the 3D models of fossil whales from Cerro Ballena using a variety of techniques, including laser scanning and photogrammetry.\n \n Fossils from Cerro Ballena are between 7-9 million years old, from a geologic time known as the late Miocene. Excavations by Chilean and Smithsonian scientists revealed a diversity of individual fossil whale skeletons at this site included several different species of whales with adults and juveniles preserved as complete skeletons. The density of fossil whales at Cerro Ballena is the richest known so far in the world. Many of the fossil whale skeletons were intact, including the skull and jaws preserved in articulation with the vertebral column (or backbone), and sometimes along with the bones of the forelimbs (or flippers). Scientists used 3D models of these skeletons to score the degree of anatomical connections among the bones and measure specific aspects of how far the bones in the skeleton have shifted from their life articulation.\n \n Overall, the bones from the fossil whale skeletons at Cerro Ballena showed little sign of disturbance or scavenging by large animals, which suggests that a short time from death to burial. Geological work at Cerro Ballena pointed to the rock layers representing an ancient tidal flat. The fact that skeletons at the site were discovered only meters away from each other also suggests their bodies were concentrated at the site, likely by wave action; many of the skeletons were buried belly up, providing further evidence that the whales were already long dead by the time they arrived at the tidal flat. Together, the evidence point to ancient harmful algal blooms are the likeliest cause for the deaths of all of the animals at the site; also, it is a cause that can repeat through time, and explain the accumulation of whales and other animals at Cerro Ballena across each of the four bone-bearing layers.\n \n Although excavations of the highway expansion are now complete, fossils preserved in rock strata that extend west and east at the roadcut suggest that hundreds of more skeletons remain buried nearby. These scope and density of skeletons from the site make it unique, on par with the La Brea Tar Pits or Dinosaur National Monument in the United States.\n \n Read the scientific paper: https://royalsocietypublishing.org/doi/full/10.1098/rspb.2013.3316\n \n For more images and data from the site, see: https://www.si.edu/newsdesk/photos/cerro-ballena-fossil-whales"]},"metadata":[{"label":{"ja":["分野"],"en":["Topic"]},"value":{"ja":["古生物学"],"en":["Paleoontology"]}},{"label":{"ja":["museum"]},"value":{"ja":["デジタル化プログラム・オフィス"],"en":["Digitization Program Office"]}},{"label":{"ja":["objectType"]},"value":{"ja":["化石"],"en":["Fossils"]}},{"label":{"ja":["作成者"],"en":["Creator"]},"value":{"ja":["カルデラ古生物学博物館（チリ）（Museo Paleontologico de Caldera, Chile）"],"en":["Museo Paleontologico de Caldera, Chile"]}}],"rights":"http://creativecommons.org/publicdomain/zero/1.0/","thumbnail":[{"id":"https://3d-api.si.edu/content/document/3d_package:1f1ec6af-193f-4969-9185-dc5dd587239d/scene-image-low.jpg","type":"Image","format":"image/jpeg"}],"homepage":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/item/fossil-whale-excavation-site-mpc-675-1f1ec6","type":"Text","label":{"ja":["詳細ページ"],"en":["Detail page"]},"format":"text/html"},{"id":"https://www.si.edu/object/dpo_3d_200020","type":"Text","label":{"ja":["出典"],"en":["Source"]},"format":"text/html"}],"rendering":[{"id":"https://3d-api.si.edu/content/document/3d_package:1f1ec6af-193f-4969-9185-dc5dd587239d/fossil-whale-mpc-675-150k-2048-medium.glb","type":"Model","label":{"ja":["3Dモデル (GLB)"],"en":["3D model (GLB)"]},"format":"model/gltf-binary"}],"items":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1","type":"Scene","label":{"ja":["化石クジラ発掘地点 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675"]},"backgroundColor":"#000000","items":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/page","type":"AnnotationPage","items":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/model","type":"Annotation","motivation":"painting","body":{"id":"https://3d-api.si.edu/content/document/3d_package:1f1ec6af-193f-4969-9185-dc5dd587239d/fossil-whale-mpc-675-150k-2048-medium.glb","type":"Model","format":"model/gltf-binary"},"target":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1"}]}],"annotations":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/annotations","type":"AnnotationPage","items":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/annotation/Vh8Zkz53yUcY","type":"Annotation","motivation":["commenting"],"body":{"type":"TextualBody","value":"この化石クジラ（現場番号B31、現在はMPC 675として登録）の頭部は脊柱とつながっており、骨格が腹を上にして保存されたことを示している。この露出した頭骨の表面に保存された、骨質の眼窩と小さな耳の骨に注目してほしい。","label":"頭骨と顎","language":"ja","format":"text/plain"},"target":{"type":"SpecificResource","source":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1","type":"Scene"}],"selector":[{"type":"PointSelector","x":-1082.9890361,"y":402.2235115,"z":-402.3418453,"normal":[0.4813399,0.7474465,0.4578599]}]}},{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/annotation/mvZ08kA1lUlo","type":"Annotation","motivation":["commenting"],"body":{"type":"TextualBody","value":"この標本の多くの肋骨のうちの1本で、動物の肋骨籠のおおよその領域に保存されているが、骨は生前の位置にはない。この骨格は、産地の2番目の化石包含層（すなわちBL-2）から採集された。","label":"肋骨","language":"ja","format":"text/plain"},"target":{"type":"SpecificResource","source":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1","type":"Scene"}],"selector":[{"type":"PointSelector","x":-334.8498847,"y":284.3619105,"z":215.6003314,"normal":[-0.0606771,0.9975359,-0.0352193]}]}},{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/annotation/3XlwxX5WakIK","type":"Annotation","motivation":["commenting"],"body":{"type":"TextualBody","value":"長い列をなす多くの椎骨のうちの1つ――化石クジラの背骨である。これらの椎骨が、頭骨や肋骨籠とつながった状態でひとまとまりに保存されていたことは、この骨格が動物の死後まもなく埋没したことを示唆している。","label":"椎骨","language":"ja","format":"text/plain"},"target":{"type":"SpecificResource","source":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1","type":"Scene"}],"selector":[{"type":"PointSelector","x":918.4369845,"y":213.2587073,"z":-408.6930059,"normal":[-0.0508018,0.9964968,-0.0664331]}]}},{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1/annotation/ZYKAtYAERym3","type":"Annotation","motivation":["commenting"],"body":{"type":"TextualBody","value":"セロ・バジェナの発掘に用いられた資材の一部。黒いフェルト製の防水シートは、研究とデジタル化の合間に骨格を覆い、石膏ジャケットで包んで現場から搬出する前に、風や砂塵から守るのに役立った。","label":"防水シート","language":"ja","format":"text/plain"},"target":{"type":"SpecificResource","source":[{"id":"https://archivebase.ldas.jp/na-kamura-1263/smithsonian-3d/api/iiif/4/fossil-whale-excavation-site-mpc-675-1f1ec6/scene/1","type":"Scene"}],"selector":[{"type":"PointSelector","x":1265.8687398,"y":-537.2969299,"z":-2313.0878397,"normal":[0.1764028,0.8976942,0.4037664]}]}}]}]}]}