사용자:Pi.C.Noizecehx/작업장
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연부조직편집2005년 3월, 노스캐롤라이나 주 주립 대학의 마리 히그비 슈바이처는 사이언스 지에서, 화석화된 6800만 년 전의 티란노사우루스의 골수 공동을 복원했다고 발표하였다. 그 뼈는 (비록 어쩔 수 없었지만) 배로 운반하기 위해 부서졌고, 복원되지도 않았다. 엄밀히 말하면, 그것은 슈바이처는 연부조직만을 검사하기를 바라고 있었기 때문이다.[1] MOR 1125로 지정된 그 공룡은 was previously excavated from the Hell Creek Formation. Flexible, bifurcating blood vessels and fibrous but elastic bone matrix tissue were recognized. In addition, microstructures resembling blood cells were found inside the matrix and vessels. The structures bear resemblance to 타조의 혈세포들과 vessels. Whether an unknown process, distinct from normal fossilization, preserved the material, or the material is original, the researchers do not know, and they are careful not to make any claims about preservation.[2] If it is found to be original material, any surviving proteins may be used as a means of indirectly guessing some of the DNA content of the dinosaurs involved, because each protein is typically created by a specific gene. The absence of previous finds may merely be the result of people assuming preserved tissue was impossible, therefore simply not looking. Since the first, two more tyrannosaurs and a hadrosaur have also been found to have such tissue-like structures.[1] Research on some of the tissues involved has suggested that birds are closer relatives to tyrannosaurs than other modern animals.[3] 2007년 4월 사이언스지에 실린 연구들에서, 아사라와 동료들은 티란노사우루스의 뼈에서 관찰된 일곱 개의 콜라겐 단백질의 배열은, 닭, 개구리, 그리고 영원(newt)의 그것과 대단히 비슷하다는 사실을 밝혀냈다. 수백만 년 전의 생명체들에게서 나온 이 발견, along with similar traces the team found in a mastodon bone at least 160,000 years old, upends the conventional view of fossils and may shift paleontologists' focus from bone hunting to biochemistry. Until these finds, most scientists presumed that fossilization replaced all living tissue with inert minerals. Paleontologist Hans Larsson of McGill University in Montreal, who was not part of the studies, called the finds "a milestone", and suggested that dinosaurs could "enter the field of molecular biology and really slingshot paleontology into the modern world."[4] 그에 이어진 2008년 4월의 연구들은 티란노사우루스와 현대의 새들 사이의 가까운 관계를 알려주었다. 하버드 대학의 생물학자 크리스 오르간은 "더 많은 정보가 있었다면, 그들은 아마 티란노사우루스를 악어, 닭, 타조 사이의 어디에 놓을지 알 수 있었을 것이다."라고 말하였다. 공저자 존 M. 아사라는 "또한 우리는 티란노사우루스가 악어나 도마뱀 같은 현대 파충류와보다 조류와 더 가까움을 보였다."라고 덧붙였다.[5] The presumed soft tissue was called into question by Thomas Kaye of the University of Washington and his co-authors in 2008. They contend that what was really inside the tyrannosaur bone was slimy biofilm created by bacteria that coated the voids once occupied by blood vessels and cells.[6] The researchers found that what previously had been identified as remnants of blood cells, because of the presence of iron, were actually framboids, microscopic mineral spheres bearing iron. They found similar spheres in a variety of other fossils from various periods, 암모나이트를 포함한. In the 암모나이트 they found the spheres in a place where the iron they contain could not have had any relationship to the presence of blood.[7] |