化石(fossi)l通常是指那些保存在地层中的地质历史时期古生物留下的遗体或者痕迹。然而,化石的记录存在不完备性,并非所有的史前生物都能保存下来成为化石。化石的形成与保存都需要十分严格的条件:首先,化石的形成与古生物本身有着非常重要的关系,通常生物的硬体(如脊椎动物的骨骼、腕足动物的壳体和 Fossil l Generally refers to the remains or traces left by paleontologists during the geological history preserved in strata. However, there are incomplete records of fossils, and not all prehistoric creatures can be preserved as fossils. Fossil formation and preservation are subject to very strict conditions: First, the formation of fossils and paleontology itself has a very important relationship, usually biological hardware (such as vertebrate bones, brachiopods shell and