论文部分内容阅读
在西双版纳州的景洪县,一个叫勐宋的地方生长着一片树林子,树高只有八、九米,棵棵树都是光光的树干,没有枝桠,只是顶端有一片片大绿叶,那些绿叶像鸟类的羽毛,向两边分去,有几米长.这便是冰川时期留下来的原始植物——树蕨.科学家们介绍,树蕨是世界上最早的植物.大约在一亿年前,世界上的大多数地区还是一片汪洋大海,现今的五大洲也还是连在一起的时候,陆地上就生长着高大的蕨类植物,比今天见到的树蕨要高大几倍甚至几十倍.但是,沧海桑田,地质变迁的结果使那些高大的蕨类
In Jinghong County of Xishuangbanna Prefecture, a place called Mengsong grew a tree with only eight or nine meters of trees, and all the trees were bare trunks without branches and branches, but there was a piece of big green leaves at the top. Green leaves like bird feathers, divided to two sides, a few meters long.This is the original plant left in the glacial period - tree ferns.Scientists introduced the tree fern is the world’s first plant.About 100 million years ago In most parts of the world, there is still a sea of vast oceans. Nowadays, the five continents are still connected together. There are tall ferns growing on land, which is several times or even tens of times higher than the tree ferns seen today However, the vicissitudes of life, the result of geological changes so that those tall ferns