古生代
Paleozoic, geological era from about 545 to 250 million years ago
词频 2.5
含义
- Paleozoic, geological era 545-250m years ago, covering Cambrian 寒武紀|寒武纪, Ordovician 奧陶紀|奥陶纪, Silurian 志留紀|志留纪, Devonian 泥盆紀|泥盆纪, Carboniferous 石炭紀|石炭纪, Permian 二疊紀|二叠纪
Paleozoic, geological era from about 545 to 250 million years ago
词频 2.5