It is animals and plants which lived in or near water whose remains are most likely to be preserved, for one of the necessary conditions of preservation is quick burial, and it is only in the seas and rivers, and sometimes lakes, where mud and sit have been continuously deposited, that bodies and the can be rapidly covered over and preserved.
只有生活在水中或水邊的動(dòng)植物尸體最有可能被保存下來,因?yàn)楸4娴谋匾獥l件之一是迅速掩埋,所以只有在泥沙不停淤積的海洋和江河里,有時(shí)在湖泊里,尸體之類的東西才能被迅速地覆蓋而保存下來。