气候驱动的人口在性别决定系统中的分歧.
Ido Pen1, Tobias Uller, Barbara Feldmeyer
1Theoretical Biology Group, University of Groningen, PO Box 14, 9750 AA Haren, the Netherlands. i.r.pen@rug.nl
Nature
|October 29, 2010
概括
不同高度的种群表现出不同的性别确定方法,由气候驱动. 这项研究解释了环境因素如何塑造脊椎动物性别决定多样性的演变.
科学领域:
- 进化生物学 进化生物学
- 发展生物学 发展生物学
- 生态生态学 生态生态学
背景情况:
- 脊椎动物的性别决定表现出多种机制,包括遗传和温度相关的因素.
- 这种多样性背后的进化驱动因素,特别是在物种内部,尚未得到充分理解.
- 了解这些驱动因素对于理解脊椎动物进化生态至关重要.
研究的目的:
- 研究脊椎动物物种内不同性别决定机制的进化原因.
- 为了确定环境因素,如气候,如何影响性别确定策略.
- 开发一个框架,整合性别决定变化的发育,生态和进化方面.
主要方法:
- 在活产的高度梯度中对性别确定机制 (温度依赖与基因型) 的比较分析.
- 用现场数据进行参数化的理论模型的开发和应用,以预测性别确定系统的分歧.
- 评估气候对生命史和温度波动的影响,以了解选择压力.
主要成果:
- 不同气候极端的活生生的表现出不同的性别确定系统:低地依赖温度,高地基因型.
- 一个理论模型准确地预测了这种海拔差异及其对年性比变化的影响.
- 气候对生命史和温度变化的影响推动了不同高度的性别决定上不同的自然选择.
结论:
- 性别确定系统中的特定内分歧是适应性的,由表型可塑性和生态选择驱动.
- 气候作为一个关键的选择性压力,影响生命史和温度波动,塑造性别决定.
- 这项研究为了解脊椎动物性别决定多样性的发育,生态和进化基础提供了一个统一的框架.
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