鳥類のハイブリッドゾーン全体に二次性羽毛の特徴が片方向に広がる
Science (New York, N.Y.)
|June 11, 1993
まとめ
性選択は,遺伝子フローの障壁があっても,鳥類のハイブリッドゾーンに男性特性の急速な拡散を促します. この研究では,マナカス・マナキンを調査し,交配の成功がハイブリッド集団の特性の進化にどのように影響するか明らかにしました.
科学分野:
- 進化生物学の進化生物学について
- 鳥類学 鳥類学とは,鳥類学である.
- 遺伝学 遺伝学とは
背景:
- ハイブリッドゾーンは,異なる種が交配する場所で形成されます.
- 理論によると,ポジティブ・セレクションによる特徴は,遺伝子フローの障壁を克服することができる.
- マナカス・マナキンは,特性の侵入を研究するためのモデルを提供します.
研究 の 目的:
- 鳥類のハイブリッドゾーンにおけるクラインのパターンを調査する.
- 特徴の侵入における性選択の役割を決定する.
- ハイブリッドゾーンに広がる急速な特性の理論的予測をテストする.
主な方法:
- Manacus candeiとM. vitellinusにおける非偶然のクラインの分析.
- ハイブリッド集団の遺伝子および形態測定評価.
- レークの繁殖システムと交配の成功率の評価.
主要な成果:
- マナカスハイブリッドゾーンで異常な非偶然のクリンが観察されました.
- M. vitellinusの男性二次性特性は,M. candeiの集団に侵入しています.
- 雄性性性交配における高度に歪んだ交配の成功は,強い性選択を示唆している.
結論:
- 性選択は,ハイブリッドゾーン間の適応特性の急速な侵入を促すことができます.
- 非偶然のクラインは,男性性特性の選択によって説明される.
- 発見は,遺伝子フローの障壁にもかかわらず,選択主導の特性の拡散の理論的モデルをサポートしています.
関連する概念動画
02:29Hybrid Zones
Hybrid zones are narrow regions where two closely related species interact, mate, and produce hybrids. Relative to either parent species, hybrids may possess distinct phenotypic or genetic differences that impact their survival and reproductive success. The genetic variances introduced by hybridization influence species diversity and speciation processes within the hybrid zone.Gene flow and natural selection are evolutionary mechanisms that shape the outcome of a hybrid zone. Gene flow...
01:31Formation of Species
Speciation describes the formation of one or more new species from one or sometimes multiple original species. The resulting species are discrete from the parent species, and barriers to reproduction will typically exist. There are two primary mechanisms, speciation with and without geographic isolation—allopatric and sympatric speciation, respectively.Allopatric SpeciationIn allopatric speciation, gene flow between two populations of the same species is prevented by a geographic barrier, like...
01:17Understanding Species and Reproductive Barriers
A species is a group of organisms that interbreed and produce fertile offspring. Typically, individuals of the same species appear similar and share common characteristics due to their highly similar genomes. However, not all organisms that look alike are members of the same species. Various mechanisms keep most species discrete. While some mechanisms prevent reproductive behavior and fertilization (pre-zygotic isolation), others prevent the production of fertile offspring after mating has...
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.
02:16Genetics of Speciation
Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.The genetics of speciation involves the different traits or isolating mechanisms preventing gene exchange, leading to reproductive isolation. Reproductive isolation can be due to reproductive barriers that have effects either before or after the formation of a zygote. Pre-zygotic mechanisms prevent fertilization from occurring, and post-zygotic mechanisms...
00:49Complementation Tests
A complementation test is a simple cross to identify whether the two mutations are located on the same gene or different genes. It was first performed by Edward Lewis in the 1940s while working on fruit flies. He developed the test to identify the location and arrangement of different mutations on chromosomes.
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...