一个Silurian装甲的aplacophoran以及对软体动物类型的含义
Mark D Sutton1, Derek E G Briggs, David J Siveter
1Department of Earth Sciences and Engineering, Imperial College London, London SW7 2BP, UK. m.sutton@imperial.ac.uk
Nature
|October 6, 2012
概括
一个新发现的化石,Kulindroplax perissokomos,提供了证据,没有外的Aplacophora与子有关. 这一发现澄清了类类的进化起源.
科学领域:
- * 考古学 古生物学
- * 进化生物学 进化生物学
- * 无脊椎动物动物学
背景情况:
- *主要的软体动物种类之间的进化关系,特别是与Polyplacophora () 相对的Aplacophora (没有的软体动物) 的位置,仍然存在争议.
- *以前的假设表明,阿普拉科福拉是波利普拉科福拉的基底群或姐妹群,形成了Aculifera类.
- *最近的化石发现支持Aculifera假设,但一个明确链接aplacophoran和polyplacophoran特征的化石失踪了.
研究的目的:
- * 描述一种新的化石物种,弥合了阿普拉科法拉和波利普拉科法拉之间的形态差距.
- * 解决 Aplacophora 在 Mollusca 中的遗传学位置.
- *以更大的信心重建类类的进化起源.
主要方法:
- *发现并描述了一种新的化石物种, *Kulindroplax perissokomos gen. et sp. nov.*,来自西鲁里亚时期的赫雷福德郡仓库.
- *使用物理光学断层扫描的化石样本的三维重建.
- * 植物遗传学分析,纳入新的化石数据.
主要成果:
- * Kulindroplax perissokomos*的描述,这是一种化石,其体型呈现出类似阿普拉科福兰的身体特征和类似基顿的门.
- * 遗传学分析将 Kulindroplax perissokomos 和其他古色素化类动物列为皇冠群 aplacophorans.
- * 化石为Aculifera假设提供了强有力的支持,将Aplacophora和Polyplacophora联系起来.
结论:
- * 化石 * Kulindroplax perissokomos * 证明了阿普拉科福兰和多普拉科福兰之间的过渡形式.
- * 这一发现解决了关于Aplacophora的位置的长期争论,支持它们在Aculifera类中与Polyplacophora的姐妹关系.
- *这些发现显著提升了我们对软体动物早期进化和多样化的理解.
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