最も古くから知られている人類類の頭蓋骨後化石と,より高い霊長類の初期の進化
D L Gebo1, M Dagosto, K C Beard
1Department of Antrophology, Northern Illinois University, DeKalb 60115, USA. dgebo@niu.edu
Nature
|April 5, 2000
まとめ
初期の霊長類のエオシミアスの足骨の化石は,重要な解剖学的特徴を明らかにしています. これらの発見は,エオシミアスが人類型であったことを確認し,猿,類人猿,人間の進化的起源を明らかにした.
科学分野:
- パレオントロジー・パレオントロジー
- 霊長類の進化について
- アントロポイドの起源
背景:
- エオシミエ科 (Eosimiidae) の霊長類は,人類類の起源を理解する上で極めて重要です.
- 以前の知識は,歯とペトロサルの残骸に限定され,遺伝学的な不確実性を引き起こしました.
- Eosimiidaeの化石は中国とミャンマーで発見されています.
研究 の 目的:
- 中エオセンのエオシミアスの新しい化石の足骨を記述するために.
- 霊長類の進化におけるEosimiidaeの系統遺伝的位置を明確にするために.
- エオシミアスの人類形状の解剖学的証拠を提供するために.
主な方法:
- 中国の中世エオセンの堆積物から化石化したエオシミアスの足骨の発掘と分析.
- エオシミアス・ターサルの比較解剖学的分析を,現生の人類類類類と化石の人類類類と比較した.
- 新しい脳後の骨格データを組み込んだ系統遺伝分析.
主要な成果:
- エオシミアス・ターサルは,現存する人類類と化石人類類と共有する,派生した解剖学的特性を表している.
- これらの特徴は,EosimiasをAnthropoidea.の中に分類することを支持しています.
- 初期のアンスロポイドの後頭蓋骨は,原始的な特徴と派生した特徴の混合を示しています.
結論:
- 新しい化石の証拠は,初期の人類動物であるエオシミアスの立場を固める.
- これは,人類類と他の霊長類群の間の進化的関係を明らかにする.
- 初期の人類類は,いくつかのプロシミアのような特徴を保持したハプロリン祖先から進化した.
さらに関連する動画
関連する概念動画
01:23Phylogeny
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire...
02:35What is Evolutionary History?
Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.Phylogenetic trees illustrate the evolutionary relationships among these organisms. Scientists infer organisms’ common ancestry by evaluating shared morphological and genetic characteristics. Together, the fossil...
02:56The Fossil Record
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...
02:31Synteny and Evolution
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
01:14Cranial Bones: Superior and Posterior View
The superior view of the cranium shows the frontal and paired parietal bones.
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
01:22Sutures of the Skull
The human skull is composed of several bones that come together to protect the brain and support the structures of the face. The junctions where these bones meet are called sutures.
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...