Still, their fossilization required a suite of factors: a slow rate of decay of soft tissues, little scavenging by other animals, a lack of swift currents and waves to jumble and carry away small bones, and fairly rapid burial.
英
美
- 但是它们的石化需要一系列因素:软组织的腐烂速度缓慢,很少被其它动物残食,缺少混杂、冲走小骨头的快速水流和波浪,以及相当快地被掩埋。