异常甲基体干肢同质性由一个巨大的过器料器和配对的片揭示出来
Peter Van Roy1, Allison C Daley2, Derek E G Briggs3
11] Department of Geology and Geophysics, Yale University, PO Box 208109, New Haven, Connecticut 06520, USA [2] Research Unit Palaeontology, Department of Geology and Soil Science, Ghent University, Krijgslaan 281/S8, B-9000 Ghent, Belgium.
Nature
|March 13, 2015
概括
新的化石显示,异常类体板与关节动物四肢相同,澄清了它们在欧类动物进化中的基本位置. 这些巨大的过食节足动物突出显示了大奥尔多维纪生物多样化事件.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 关节动物科学 关节动物科学
背景情况:
- 特别保存的古老生代化石为关节动物进化和原生提供了洞察力.
- 异常类动物,干节肢动物,是了解早期节肢动物关系和坎布里亚生态学的关键.
- 异常类动物的树干形态仍然是争论的主题.
研究的目的:
- 为了描述来自摩洛哥早期奥尔多维纪Fezouata生物群的新异常caridid标本.
- 为了阐明异常类体与关节动物体四肢的同质性.
- 为了澄清异常caridids在euarthropods中的遗传学位置.
主要方法:
- 来自Fezouata生物群的新化石标本的描述.
- 与其他干系关节动物的干部形态的比较分析.
- 遗传学分析以确定异常糖的位置.
主要成果:
- 新的标本显示背部和腹部的树干板,背部板的底部设置叶片.
- 腹腔是同类的与lobopodous行走的四肢和euarthropod的内脚.
- 背面的片和座位叶片与状龙类动物和"坎布里亚甲四肢"类动物同源.
- 异常类体代表了类四肢的融合前阶段,证实了基底欧类茎的位置.
- 费祖阿塔 (Fezouata) 分类表现出巨大的尺寸 (大于2米) 和过式养的适应性,表明了新的养生态.
- 这表明在大奥尔多维纪生物多样化事件期间建立了发达的浮游生物生态系统.
结论:
- 马洛卡里迪德 (Anomalocaridid) 干代表了关节动物肢体进化的过渡阶段.
- 证实了Anomalocaridids是基底欧类动物,而不是关节动物王冠成员或旋风性神经虫.
- 巨型过式食异常类动物的进化反映了奥尔多维纪海洋生态系统的重大变化.
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