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古生代干的非虫幼虫

Tetsuto Miyashita^1,2,3,4, Robert W Gess⁵, Kristen Tietjen^6,7

¹Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL, USA. TMiyashita@nature.ca.

|March 11, 2021

概括

化石幼虫挑战了ammocoetes (过食幼虫) 代表原始脊椎动物的祖先的观点. 这些古老的幼虫有成年人的特征, 暗示 ammocoetes 是现代鱼的特征.

科学领域:

古生物学
进化生物学
脊椎动物的解剖学

背景情况:

现代的幼虫阶段 Ammocoetes 在历史上被认为是早期脊椎动物进化的模型.
它们的食生活方式和表面上类似于两动物的外观形成了关于脊椎动物起源的假设.
然而,ammocoete阶段的进化古代缺乏直接的化石证据,这引发了对其原始状态的质疑.

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In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, Rückert observed LBCs in shark egg cells and coined the term "lampbrush chromosomes" because they looked like brushes used to clean kerosene lamps.
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