The limited food and space on small islands can often lead to intense competition.
岛屿上有限的食物和空间时常激起激烈的竞争。
But some islands are immense.
但有些岛屿却幅员辽阔。
More like miniature continents.
更像是一块小型大陆。
And these provide opportunities for life to experiment and evolve.
这为不同生命的进化与试验提供了机会。
Madagascar is one of the biggest islands and also one of the oldest,
马达加斯加是地球上最大的岛屿之一,也是最古老的岛屿之一,
having split away from Africa over 120 million years ago.
它在一亿两千万年前就已经脱离非洲大陆。
With time and isolation,
随着时间流逝与地理隔断的出现,
its animals have adapted to take advantage of every available niche.
岛上的动物们不断适应充分利用一切可用资源。
The island now has some 250,000 different species, most found nowhere else on Earth.
这座岛上现存约二十五万不同的物种,大部分都是该地区特有种。
These are not monkeys, but lemurs.
这些不是猴子,而是狐猴。
From a single ancestor, about 100 different types have evolved.
他们从同一个祖先进化出一百个不同的种。