它们的种子的顶端向上生长，其距离地面的高度刚好可以接触到风；它们的体型大小也刚好是生长所需的尺寸；它们的茎是空心的，且仅仅是通过体内的含水量来保持自身的坚挺。

Their seed heads raised just high enough above the ground to catch the wind, the plants are no bigger than they need be, their stems are hollow, and all the rigidity comes from their water content.

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