在眼中基因变异的条件依赖信号
P David1, T Bjorksten, K Fowler
1Department of Biology, University College London, UK.
Nature
|July 26, 2000
概括
遗传差异影响着雄性眼在不同的食物条件下如何展示装饰品. 性装饰的这种变化,独立于身体大小,表明女性通过选择伴侣获得遗传利益.
科学领域:
- 进化生物学 进化生物学
- 动物行为 动物行为
- 遗传学 是一个遗传学.
背景情况:
- 性选择理论认为,男性装饰标志着遗传质量,表现通常取决于环境条件.
- 以前的研究表明,环境压力增加了性装饰的条件依赖.
研究的目的:
- 研究眼 (Cyrtodiopsis dalmanni) 中男性性装饰的条件依赖性表达的遗传基础.
- 确定遗传变异是否是男性装饰品对环境压力的反应的基础,特别是食物质量的变化.
主要方法:
- 在可变食物质量的控制条件下研究了茎眼 (Cyrtodiopsis dalmanni).
- 测量了男性的眼睛距离,女性的眼睛距离和翅膀长度 (男性和女性),以评估特征表达.
- 分析了性和非性特征的条件依赖表达的遗传变异,并考虑了体型.
主要成果:
- 根据食物质量,发现男性性装饰品 (眼) 的条件依赖表达有显著的遗传变异.
- 观察到,一些男性基因型在各种条件下保持了很长的眼睛跨度,而另一些则随着食物质量下降而减少.
- 非性特征显示条件依赖主要与身体大小相关,与男性的性装饰不同.
结论:
- 男性装饰品对环境压力的反应中的遗传变异对于性选择至关重要.
- 男性的性装饰品的条件依赖的表达,独立于身体大小,为女性选择伴侣提供了可靠的信号.
- 这些发现支持这样一个假设:基于装饰品的女性伴侣选择给后代带来了遗传上的好处.
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