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澄江生物群、凯里生物群、加拿大布尔吉斯生物群和西伯利亚藻群中均有丰富的藻类化石。根据前寒武纪宏观藻类的分布以及凯里生物群和布尔吉斯页岩生物群中藻类和后生动物的相似性 ,讨论了前寒武纪至中寒武世期间生物地理分区的控制因素。对几个生物群中的藻类化石和后生动物化石的对比研究发现 ,在相近的纬度范围内 ,动植物化石组合特征非常相似 ;而纬度有明显差异时 ,藻类生物群及后生动物群也具有明显的差异。由于后生生物在前寒武纪至中寒武世期间具有低的演化程度和分异能力 ,因此生物地理分布的主要控制因素是古纬度。而Schopf(1976 )的生物地理分区模式不适合这一时期的生物地理分区。结合前寒武纪至中寒武世后生生物化石的分布情况 ,建立了前寒武纪—中寒武世时期的生物地理分区模式。这个模式较好地解释了分布在北美大陆和华南大陆上的寒武纪生物群相似的原因。
The Chengjiang biota, Kaili biota, Canada Burqisi biota and Siberian algae are rich in algae fossils. Based on the distribution of macro-algae in the Precambrian and the similarities between algal and metazoan species in the Kaili and Burganis shale biota, the controlling factors of the biogeographical zoning during the Precambrian to Middle Cambrian period are discussed. Comparative studies on algae fossils and metazoan fossils in several biota found that within the similar latitudes, the fossil assemblages of animals and plants are very similar, while those with obvious differences in latitude also have obvious algal biota and metazoan fossils The difference. As the metazoan has a low degree of evolution and differentiation during the Precambrian to Middle Cambrian periods, the dominant controlling factor in biogeographical distribution is paleo-latitude. Schopf’s (1976) biogeographical zoning model is not suitable for this period of biogeographical zoning. According to the distribution of the fossil from the Precambrian to Middle Cambrian epoch, a model of biogeographical division from Precambrian to Middle Cambrian period was established. This model provides a good explanation for the similarities in the Cambrian biota that populate North America and South China.