子证据为起源的IsoetaleanLycopsids的证据?
Jiří Bek1, Jana Votočková Frojdová1
1Institute of Geology, Academy of Sciences of the Czech Republic, Rozvojová 269, 16500 Prague, Czech Republic.
Life (Basel, Switzerland)
|July 29, 2023
概括
一个新的假设表明,单个类类动物是从类动物进化而来的,而不是原型类动物. 这取决于三颗尖端乳头在肌上存在,这种特征起源于西卢里亚时期.
科学领域:
- 古植物学是古植物学.
- 进化生物学 进化生物学
- 帕利诺学 (Palynology) 是一个临床学科.
背景情况:
- 异种类型的Lycopsids的进化起源仍然是一个辩论的主题.
- 以前的假设表明,它起源于德纪期间的protolepidodendralean lycopsids.
- 古生物学数据为植物进化提供了关键的见解.
研究的目的:
- 为了提出一个新的假设,以确定异构菌的起源.
- 根据子形态学重新评估Lycopsids的进化血统.
- 为了研究三种角乳头在肌中的遗传学意义.
主要方法:
- 对古生物学数据的分析,重点是肌形态学.
- 在isoetalean,selaginellalean和protolepidodendralean分类之间比较子特征.
- 考察从西卢里亚到纪的化石记录.
主要成果:
- 在近端肌胞表面上存在三个尖端乳头,这是区分异类和类的关键特征.
- 三个角乳头首先出现在较低的Silurian rhyniophytoid植物中.
- 子有三个尖端乳头,形成一个连续的血统,从丝纪到纪.
结论:
- 绝缘类类可能是直接从类生物进化而来的,而不是原始类类.
- 三个顶端乳头的存在支持了单独的Lycopsids的一个独特的进化轨迹.
- 这一发现挑战了以前关于柳科类类型的假设,并强调了古生物学证据的重要性.
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