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化石证据表明,克隆碎片化,六倍对称性和小行星皮动物的生态生活方式之间的古老联系
Ben Thuy1, Lea D Numberger-Thuy1,2, Jürgen Härer3
1Department of Palaeontology, Natural History Museum Luxembourg, 25 rue Münster, 2160 Luxembourg.
Proceedings. Biological sciences
|May 15, 2024
概括
化石脆脆的恒星揭示无性繁殖 (fissiparity) 在罗纪晚期存在. 这项研究确定了最古老的Ophiactidae家族成员,证明了皮动物中克隆分裂的早期演变.
科学领域:
- 古生物学的古生物学
- 海洋生物学 海洋生物学
- 进化生物学 进化生物学
背景情况:
- 通过裂变性无性繁殖在一些小行星动物中很常见,尤其是ophiactid脆脆的恒星.
- 分裂性脆性恒星通常有六个手臂,生活在宿主上,并使用克隆碎片化来殖民息地和范围扩张.
- 虽然分离性生物学的生物学和生态学已被理解,但它的进化和地质历史在很大程度上是未知的.
研究的目的:
- 为了研究易裂恒星中裂变性的进化起源和地质历史.
- 描述一个来自罗纪晚期的六臂脆星的新化石物种.
- 为了推断化石的遗传位置和繁殖策略.
主要方法:
- 来自德国罗纪晚期的化石形六臂脆星的描述.
- 遗传学推断以确定化石的进化关系.
- 形态分析,以评估指示裂变性特征.
主要成果:
- 发现了一颗特殊的化石脆星,Ophiactis hex sp. 新,来自罗纪晚期.
- 遗传学分析将*Ophiactis hex*作为已知最古老的Ophiactidae家族成员.
- 化石表现出六臂对称性和再生特征,表明裂变性.
结论:
- 化石证据表明,在罗纪晚期,在小行星皮动物中建立了分裂性.
- *Ophiactis hex*提供了Ophiactidae家族中无性繁殖的最早的化石证据.
- 这一发现揭示了易碎星的早期进化和繁殖策略的多样化.
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