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形态上的创新并没有推动中生代-生代手足类动物的多样化

Zhen Guo¹, Michael J Benton², Thomas L Stubbs³

¹State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Wuhan, China.

Nature ecology & evolution

|July 25, 2024

概括

在二叠纪/三叠纪大灭绝之后,足动物的多样性下降了,但它们的形态差异仍然很高. 灭绝后的足动物订单适应了新的环境,但有限的多样化解释了它们目前的数量较低.

科学领域:

古生物学的古生物学
进化生物学进化生物学
海洋生物学海洋生物学

背景情况:

甲类 (Phylum Brachiopoda) 是在波斯/三叠纪大灭绝 (PTME) 之前的主导的海洋群体.
在PTME之后,足动物的多样性大幅下降,成为海洋生态系统的次要组成部分.
在PTME之后,足动物形态创新与多样性下降之间的关系仍然不太清楚.

研究的目的:

分析四个主要的中生代-古生代臂足动物种群的形态进化.
了解足动物的形态创新如何应对PTME后的环境变化和多样性转变.
调查导致现代足动物贫困的因素.

主要方法:

对3亿年来的形态进化分析 (百米纪-四季纪).
检查四个主要的手足类:Terebratulida,Rynchonellida,Spiriferinida和Athyridida的命令.
形态空间占用,进化差异和通用丰富性的比较.

主要成果:

臂足动物的形态差异达到或超过了PTME前的水平,尽管一般的基因丰富性较低.
所有四个分析的足动物种群都在适应波斯后环境时利用了新的形态空间.
形态空间的占用和多样性的演变表明,高灭绝率和有限的多样化导致了现代足动物的稀缺.

结论:

在PTME后的足动物进化显示了形态差异和通用丰富性的脱.
适应新的环境需要利用新的形态空间,但这并没有导致显著的多样化.
高的灭绝率和缺乏足够的多样化,足以解释足动物今天的边缘作用.

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