giraffe's long neck長(zhǎng)頸鹿的脖子 　　Why the giraffe's neck is so long？ The giraffe's ancestors didn't have such a long neck. Long， long ago， the trees on the earth grew taller and taller. The giraffes at that time had to stretch out their necks to reach the tree leaves. Those with short necks died of starvation， while the long-necked giraffes survived. The long neck is heredity of the giraffes. 　　長(zhǎng)頸鹿的脖子為什么那么長(zhǎng)？實(shí)際上長(zhǎng)頸鹿的祖先的脖子也不是太長(zhǎng)。在很早的時(shí)候，因?yàn)榈厍蛏系臉淠驹介L(zhǎng)越高，長(zhǎng)頸鹿為了吃到樹上的葉子，就必須伸長(zhǎng)脖子去吃樹葉。脖子短的長(zhǎng)頸鹿因?yàn)殚L(zhǎng)期吃不上食物，就死去了，剩下脖子長(zhǎng)的長(zhǎng)頸鹿。而且隨著時(shí)間的推移，長(zhǎng)頸鹿為了吃到更多的樹葉，就把脖子長(zhǎng)的特點(diǎn)遺傳了下來(lái)。所以現(xiàn)在我們看到的長(zhǎng)頸鹿的脖子都特別長(zhǎng)。