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通过对华南二叠纪腕足类壳饰的研究和个体大小的统计分析表明,长身贝类的形态演化呈现以下几个方面的规律:从乌拉尔世(早二叠世)到晚二叠世吴家坪期,同心饰或放射饰较强的种(类型3)所占的百分比呈现先减小再增大的变化趋势;与此同时,同心饰或放射饰较弱的种(类型2)所占的百分比呈现先增大再减小的趋势.从晚二叠世吴家坪期到长兴期,同心饰或放射饰较强以及较弱的种所占的百分比均呈增加的趋势.从乌拉尔世到晚二叠世长兴期壳刺发育的种(类型4)所占的百分比一直保持减小的趋势.从吴家坪期到长兴期(包括过渡层)部分种表现出壳体小型化的趋势.二叠纪长身贝类壳饰和个体大小的演化规律与二叠纪末生物大绝灭前以及绝灭过程中的贫氧、食物短缺、海平面变化以及底质的变化相关.
Based on the research on shell and shell of Brachiopods in South China and the statistical analysis of individual size, the morphological evolution of the long shellfish showed the following rules: from Ural (Early Permian) to late Permian Wujiaoping The percentage of species (type 3) with stronger period, concentric or radiological decoration showed the trend of first decreasing and then increasing. At the same time, the percentage of species with concentric or radiological decoration (Type 2) The percentage showed the trend of first increasing and then decreasing.From the Permian Wujiaping period to Changxing period, the percentage of concentric or radiating ornaments with stronger and weaker species showed an increasing trend.From Ural to the late two The percentage of species (type 4) developed during the Changxing period of the Middle Stratum kept a decreasing trend, and some species from the Wujiaping period to the Changxing period (including the transitional layer) tended to be miniaturized. Body shellfish shellfish and the size of the evolution of the law of the Permian before extinction and extinction of oxygen depletion, food shortages, sea level changes and changes in sediment related.