謎めいた性比バイアスは,性的対立にもかかわらず,間接的な遺伝的利益を提供します
1Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA. robert.m.cox@dartmouth.edu
まとめ
ブラウンアノリス (Anolis sagrei) の性対立は,雌が雄のサイズに基づいて子孫の性別比率を調整することを示しています. 大きいオスはより多くの息子を産み,小さいオスはより多くの娘を産み,子孫の健康状態を最適化します.
科学分野:
- 進化生物学の進化生物学について
- 行動生態学は,行動生態学である.
- 性選択性選択性選択とは
背景:
- 性紛争は,男性と女性の生殖的関心が異なるときに発生します.
- 配偶者選択の利点は,好ましいオスが異性の低身長な子孫を生む場合,否定される可能性があります.
- 身体の大きさの性二形態は,性的な紛争の源となる可能性があります.
研究 の 目的:
- ブラウン・アノール・リザード (Anolis sagrei) の体サイズに関する性的な葛藤を調査する.
- 雌の生殖戦略が,雄のサイズに基づいて子孫の性別比率を変化させるかどうかを判断する.
- 雄のサイズに関連した子孫の性別比調整のフィットネスへの影響を評価する.
主な方法:
- ブラウンアノールで配偶者選択実験を行いました.
- 交尾中にシールの体格を操作した.
- 野生での子孫の性別比率と子孫の健康状態を測定した.
主要な成果:
- ブラウンアノールの雌は,大きなシレを持つ息子が多く,小さなシレを持つ娘が多く生じた.
- 雌の子孫の性別比率の調整は,雄のサイズと関連していた.
- 子孫の生産を娘から息子にシフトさせることで,親子のサイズが大きくなるにつれて,子孫の健康状態が最大化されます.
結論:
- 身体のサイズに関する性的紛争の解決は,配偶者選択の遺伝的利点を回復することができます.
- 子孫の性配分における女性の生殖可塑性は,性的紛争に関連するコストを軽減することができます.
- アノリス・サグレイは,性紛争と配偶者選択の進化の相互作用を理解するためのモデルシステムを提供します.
関連する概念動画
The Ratio of X Chromosome to Autosomes
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Natural Selection and Mating Preferences
The principle of natural selection posits that organisms better adapted to their environment are more likely to survive and reproduce. This principle is closely intertwined with mating preferences, a key aspect of sexual selection, which evolutionary psychologists believe is driven by instincts to propagate one's genes. Such instincts significantly influence mating behaviors and preferences between genders.
Females, due to their biological roles in conception, pregnancy, and nursing, inherently...
Females, due to their biological roles in conception, pregnancy, and nursing, inherently...
Criticisms of the Evolutionary Perspective
In a study where individuals posing as strangers offered compliments and proposed casual sex to students, the responses differed significantly based on gender. Not a single woman accepted the proposal, while 70% of the men agreed. This outcome provides a useful scenario to explore through the lens of evolutionary psychology and social learning theory, highlighting the diverse perspectives on human sexual behaviors.
Evolutionary psychology provides one explanation for these findings, suggesting...
Evolutionary psychology provides one explanation for these findings, suggesting...
Genetics 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...
Dosage Compensation
In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one Y chromosome, whereas C.elegans with one X chromosome is a male, and the one with two X chromosomes is a hermaphrodite.
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
Mate 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.


