大小选择性收获是否会侵蚀适应热应激的适应能力?
Daniel E Sadler1, Stephan van Dijk1, Juha Karjalainen1
1Department of Biological and Environmental Science University of Jyväskylä Jyväskylä Finland.
Ecology and evolution
|February 9, 2024
概括
由于过度捕捞导致的鱼群的定向选择,可能会降低它们应对热应激等环境变化的能力. 这种多样性丧失限制了适应性反应,影响了生长和生存.
科学领域:
- 进化生物学 进化生物学
- 生态生态学 生态生态学
- 水产养殖是水产养殖的一种方式.
背景情况:
- 过度捕捞对全球鱼类种群构成重大威胁.
- 针对身体大小等特征的定向选择可以减少表型多样性.
- 减少多样性对人口对环境压力的抵御能力的影响尚不清楚.
研究的目的:
- 调查定向选择是否通过降低表型多样性,损害了鱼群对热应激的反应.
- 为了比较大小选择的斑马鱼线与随机选择的线在不同温度下的适应能力.
主要方法:
- 创建了三条斑马鱼 (Danio rerio) 选择线:针对大体型的定向选择,针对小体型的定向选择,以及随机选择 (控制).
- 线路暴露在三个温度下:低 (22°C),环境 (28°C) 和高 (34°C).
- 评估了生命史 (生长,繁殖),生理 (代谢率,临界热最大值) 和行为 (活动,养) 特征.
主要成果:
- 与随机选择的线条相比,大小选择的线条在热应力下表现出较低的生长率.
- 定向选择导致了平均表型的变化,以应对热应激.
- 面向选择的人群表现出比随机选择的人群更有限的热应激反应能力.
结论:
- 方向性选择,通常是剥削的结果,可能会降低人口适应温度波动等环境压力因素的能力.
- 减少的表型多样性可能会损害鱼群对环境变化的弹性.
- 了解这些影响对于管理自然鱼类资源至关重要,这些鱼类资源面临着剥削和气候变化.
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