"塔利怪物"是一个脊椎动物
Victoria E McCoy1, Erin E Saupe1, James C Lamsdell1,2
1Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, New Haven, Connecticut 06511, USA.
Nature
|March 17, 2016
概括
塔利怪物是一个有问题的化石, 这一发现解决了长达50年的关于灭绝的动物遗传地位的争论.
科学领域:
- 古生物学
- 进化生物学
- 脊椎动物学
背景情况:
- 具有神秘形态的有问题的化石挑战了古生物学的分类.
- 50多年来,来自石灰岩时期梅森溪生物群的"塔利怪物" (Tully monster,Tullimonstrum gregarium) 在遗传学上一直存在不确定性.
- 之前的假设表明与无脊椎动物的亲属关系,如尼默特动物,多类动物,胃类动物,类动物或茎类关节动物.
研究的目的:
- 为了确定Tullimonstrum gregarium的遗传位置.
- 使用大型样本数据集分析Tullimonstrum的形态.
- 为了确定这个神秘化石的进化关系.
主要方法:
- 对1200多个Tullimonstrum标本进行了形态分析.
- 包含新的形态证据的基因分析.
- 通过比较解剖学来识别脊椎动物的关键特征.
主要成果:
- 图利蒙斯特鲁姆有牙的鼻孔,眼睛横向投射在一个硬的杆子上,以及一个带尾的细分体.
- 新的证据显示, 脊髓,软骨,囊,
- 遗传学分析将Tullimonstrum作为一个脊椎动物与 (Petromyzontida) 的干系.
结论:
- 图利蒙斯特鲁姆 (Tullimonstrum gregarium) 是一个脊椎动物,具体来说是鱼的早期亲属.
- 这种分类解决了长期存在的古生物学难题,并扩大了已知灭绝的鱼的形态多样性.
- 这项研究突显了现代遗传学方法在解读有问题的化石亲属关系方面的力量.
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