小编klo*_*kop的帖子

给定一个看起来像这样的文件：

Crab
  some text that doesn't need sorting.
  more textual descriptination
Albatross
  some text or other
  perhaps a list that needs no sorting:
    1. a
    2. bee
Dolphin
Pterodactyl
  long story about this particular animal.

我如何告诉 Vim（第 7 版）按动物名称的字母顺序对这个文件进行排序？不可能的？否则如何对这个文件进行排序？