まとめ
フォリドストロフィイドと呼ばれる化石の腕足類は,独特の"ナクレア"の貝殻の輝きを示しています. この虹彩は,天然の光学微差分格子として作用するカルシート微細構造によって引き起こされます.
科学分野:
- パレオントロジー・パレオントロジー
- バイオミネラライゼーション
- 光学物理学 光学物理学
背景:
- 化石の腕足類のフォリドストロフィード群は,特徴的な特徴で知られている.
- ナクレウス (Nacreous) とは ナクレウス (Nacreous) とは ナクレウス (Nacreous) とは
- 輝き 輝き
研究 の 目的:
- 建物の構造的基盤を調査する.
- ナクレウス (Nacreous) とは ナクレウス (Nacreous) とは ナクレウス (Nacreous) とは
- フォリドストロフィード・ブラキオポッドの輝き.
主な方法:
- 化石保存に適した技術を使用して,殻の微細構造の分析.
- カルシートの組成と殻壁の内部の配置を調べる.
主要な成果:
- ほら,ほら,ほら,ほら
- ナクレウス (Nacreous) とは ナクレウス (Nacreous) とは ナクレウス (Nacreous) とは
- 輝きは,カルシットから成る天然の光学分散格子が重ね合わせたセットから生じる.
- 貝殻壁は,貝殻表面に平行して向き合う交差したラメラ構造を示しています.
結論:
- 特定の交差したラメラー微細構造は,薄らさや反射面の発達を促進し,観察された色を生成します.
- この構造的配置は,これらの化石の腕足類のユニークな光学特性の鍵です.
関連する概念動画
01:20Mate Choice
Mate choice—the decision about whom to mate with—is a type of natural selection, since animals must reproduce to pass down their genes. Mate choice is also called intersexual selection because the behavior occurs between the sexes.
00:57Inclusive Fitness
Most altruistic behavior—in which one animal helps another at a cost to themselves—occurs between relatives. Scientists think these altruistic behaviors evolved because they increase the inclusive fitness of the animal providing help.
02:27Background and Environment Affect Phenotype
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
02:37Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
01:19Pigmentation
The color of the skin is influenced by a number of pigments, including melanin, carotene, and hemoglobin. Recall that melanin is produced by cells called melanocytes, which are found scattered throughout the stratum basale of the epidermis. The melanin is transferred to the keratinocytes via melanosomes.
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
01:24Evolution of New Traits in Microbes
Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...