最も初期のドロメオサウリドは,南米のセロポッドでした

Peter J Makovicky¹, Sebastián Apesteguía, Federico L Agnolín

¹Department of Geology, The Field Museum, 1400 South Lake Shore Drive, Chicago, Illinois 60605, USA.

Nature

|October 14, 2005

まとめ

ドロメオサウリドを含む初期のマニラプトラ恐竜は,ゴンドワナに起源がある可能性がある. 新しい南米の化石は,大陸の分離以前に存在したユニークなゴンドワナの系統の証拠を提供します.

科学分野:

パレオントロジー・パレオントロジー
進化生物学の進化生物学について
恐竜の古生物学について

背景:

マニラプトラ (鳥と爪恐竜) の進化史は,主に北半球から知られている.
ゴンドワナから発見された以前のマニラプトラ化石は不完全であり,その相性については議論されている.

研究の目的:

南米の新型で保存状態が良好なドロメオサウルスの恐竜を記述する.
マニラプトラの初期の進化とゴンドワンの分布を調査する.
大陸の分離より前の Gondwanan 系統の証拠を提供するために.

主な方法:

ほぼ完全な化石標本の記述.
進化的関係を決定するための系統遺伝分析.
ドロメオサウリドの分布に関する古生物学地理学的評価.

主要な成果:

南米で最も完全で最古のマニラプトラの発見.
独特のゴンドワンのドロメオサウリドの系統を特定した.
証拠によると,この血統はパンゲア超大陸が解体する以前から生じたという.

結論:

この発見は,マニラプトラの分布に関する以前の理解に挑戦しています.
古代の起源を持つゴンドワンのドロメオサウリドの系統の存在を支持しています.
この発見は,恐竜の進化と生物地理を再構築する上で重要な意味を持つ.

さらに関連する動画

11:55

Streamlined Sampling and Cultivation of the Pelagic Cosmopolitan Larvacean, Oikopleura dioica

Published on: June 16, 2020

03:46

A Simple Fecal Flotation Method for Diagnosing Zoonotic Nematodes Under Field and Laboratory Conditions

Published on: December 15, 2023

関連する概念動画

01:17

Drugs for Treatment of Diarrhea-Predominant IBS

Diarrhea-predominant irritable bowel syndrome (IBS-D) is a subtype of IBS characterized primarily by frequent, loose, or watery stools, abdominal pain, and abdominal discomfort. Therapeutic approaches to managing IBS-D include dietary changes, stress management techniques, and pharmaceutical interventions.
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...

01:29

Drugs for Treatment of Ulcerative Colitis in IBD

Ulcerative colitis is a chronic inflammatory condition primarily affecting the colon and rectum. The primary drugs used in the treatment of ulcerative colitis are aminosalicylates. They exhibit anti-inflammatory and immunosuppressive properties. They modulate inflammatory mediators and inhibit the activity of nuclear factor κB (NF-κB). Aminosalicylates also reduce inflammation by inhibiting prostaglandin and leukotriene production and decreasing neutrophil chemotaxis and superoxide generation.

01:27

Diversity of Protists III

Rhizaria are a diverse group of unicellular protists characterized by their threadlike cytoplasmic extensions known as pseudopodia. These structures aid in both locomotion and feeding, giving Rhizaria an amoeboid appearance. Their amoeboid morphology once led to taxonomic confusion, but molecular phylogenetics has clarified their evolutionary placement and emphasized their shared use of pseudopodia despite divergent lineages.This clade comprises diverse lineages such as Chlorarachniophyta,...

01:26

Origin of Photosynthesis

Photosynthesis represents a fundamental biological process that transformed Earth's atmosphere and paved the way for complex life. Emerging roughly 3.4–3.8 billion years ago, the earliest photosynthetic organisms harnessed light energy to produce organic compounds. These anoxygenic phototrophs used electron donors like hydrogen sulfide (H₂S) or ferrous iron (Fe²⁺), rather than water, and did not release molecular oxygen (O₂) as a byproduct. Various groups, including green sulfur and purple...

01:28

Development of the Oral Microbiota

The establishment of the oral microbiome begins before birth, challenging the long-held belief that the fetal oral cavity is sterile. The presence of oral microbes such as Streptococcus and Fusobacterium in amniotic fluid suggests that microbial exposure may occur in utero, potentially through translocation from the maternal oral or gastrointestinal tract. This early colonization primes the neonatal immune system and sets the stage for subsequent microbial succession. Maternal health,...

関連する実験動画