The Cambrian Explosion by nature is a three-phased explosion of animal body plans alongside episodic biomineralization, pulsed change of generic diversity, body size variation, and progressive increase of ecosystem complexity. The Cambrian was a time of crown groups nested by numbers of stem groups with a high-rank taxonomy of Linnaean system (classes and above). Some stem groups temporarily succeeded while others were ephemeral and underrepresented by few taxa. The high number of stem groups in the early history of animals is a major reason for morphological gaps across phyla that we see today. Most phylum-level clades achieved their maximal disparity (or morphological breadth) during the time interval close to their first appearance in the fossil record during the early Cambrian, whereas others, principally arthropods and chordates, exhibit a progressive exploration of morphospace in subsequent Phanerozoic. The overall envelope of metazoan morphospace occupation was already broad in the early Cambrian though it did not reach maximal disparity nor has diminished significantly as a consequence of extinction since the Cambrian. Intrinsic and extrinsic causes were extensively discussed but they are merely prerequisites for the Cambrian Explosion. Without the molecular evolution, there could be no Cambrian Explosion. However, the developmental system is alone insufficient to explain Cambrian Explosion. Time-equivalent environmental changes were often considered as extrinsic causes, but the time coincidence is also insufficient to establish causality. Like any other evolutionary event, it is the ecology that make the Cambrian Explosion possible though ecological processes failed to cause a burst of new body plans in the subsequent evolutionary radiations. The Cambrian Explosion is a polythetic event in natural history and manifested in many aspects. No simple, single cause can explain the entire phenomenon.

从本质上讲，寒武纪大爆炸是动物身体计划的三阶段爆炸，伴随着偶发性生物矿化、一般多样性的脉冲变化、体型变化和生态系统复杂性的逐步增加。寒武纪是由具有林奈系统（类及以上）高级分类法的许多茎类嵌套的冠类时代。一些干群暂时取得了成功，而其他干群则是短暂的，很少有分类群代表。动物早期历史中大量的茎群是我们今天看到的跨门形态差异的主要原因。大多数门级进化枝在接近它们在寒武纪早期首次出现在化石记录中的时间间隔内实现了它们的最大差异（或形态学宽度），而其他的，主要是节肢动物和脊索动物，在随后的显生宙中表现出对形态空间的逐步探索。后生动物形态空间占据的总体范围在寒武纪早期就已经很广泛了，尽管它没有达到最大差异，也没有因为寒武纪以来的灭绝而显着减少。内因和外因被广泛讨论，但它们只是寒武纪大爆发的先决条件。没有分子进化，就没有寒武纪大爆发。然而，仅靠发育系统不足以解释寒武纪大爆发。时间等效的环境变化通常被认为是外在原因，但时间巧合也不足以建立因果关系。像任何其他进化事件一样，尽管生态过程未能在随后的进化辐射中引起新的身体计划的爆发，但正是生态使寒武纪大爆发成为可能。寒武纪大爆发是自然史上的一个多神事件，表现在多方面。没有简单的单一原因可以解释整个现象。