独立向淡水环境的过渡促进了鱼的表型分歧,而不是融合
A Magnuson1, M N Dean2, J C Weaver3,4
1Department of Biology, University of Louisville, Louisville, KY 40292, USA.
Integrative and comparative biology
|April 23, 2024
概括
刺的融合进化表明,淡水入侵并没有导致强烈的形态趋同. 不同的血统发展出独特的特征,表明适应过程中的偶然性而不是决定性.
科学领域:
- 进化生物学 进化生物学
- 生态生态学 生态生态学
- 脊椎动物动物学 脊椎动物动物学
背景情况:
- 融合进化 (Convergent evolution),即类似的特征独立进化,为进化过程提供了洞察力.
- 脊椎动物从盐水过渡到淡水息地,为研究适应提供了自然实验.
- 鱼 (Dasyatidae) 曾多次在全球范围内殖民淡水环境,这是一个独特的案例研究.
研究的目的:
- 为了调查鱼在盐水到淡水入侵的频率.
- 为了比较淡水和盐水鱼谱系之间的生态和表型多样化.
- 评估淡水鱼物种之间的形态趋同程度.
主要方法:
- 分析跨大陆和群体的刺入侵频率.
- 对淡水和盐水系的生态特征和形态的比较分析.
- 形态空间分析,以评估具有相似利基的淡水物种之间的趋同.
主要成果:
- 淡水鱼虽然在形态上与海洋同类没有什么区别,但扩大了该群体的整体形态多样性.
- 像鱼类动物和软体动物这样的食用物专家占据了形态空间的不同区域.
- 在淡水鱼中观察到有限的形态趋同,无论是作为一个群体,还是跨越不同谱系共享类似的利基.
结论:
- 淡水鱼缺乏强烈的形态趋同可能是由于进化时间不足或祖先身体计划 (bauplans) 的影响.
- 进化中的偶然性,由阻力最小和选择弱的路径驱动,可以解释观察到的多样化模式.
- 鱼淡水入侵突出了时间,祖先和选择在塑造进化轨迹的复杂相互作用.
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