A theory holding that completely new types of organisms and characteristics appear at certain stages of the evolutionary process, usually as a result of an unpredictable rearrangement of the preexisting elements.层创进化论，突生进化：认为在进化过程的某些阶段会有全新的有机体和特征出现的一种理论，通常是原有元素的一种不可预知的重新排列的结果