Most oceanic islands are similar to one another in latitude and contain plants and animals typical of tropical islands.
大多数海洋岛屿彼此都纬度相近,并且都有热带岛屿典型的动植物。
This is because middle- and upper- latitude timberlines are strongly influenced by the duration and depth of the snow cover.
这是因为中纬度和高纬度地区的林木线受到积雪存留时间和厚度的强烈影响。
If they kept on going, and the next night they saw the pair of stars setting separately, then they would know that they were at a different degree of latitude.