名詞 natural selection:

1. a natural process resulting in the evolution of organisms best adapted to the environment
   同義詞：survival, survival of the fittest, selection

1. A systematic long-term change of this kind suggests the action of natural selection and indicates that female skeletal characteristics confer greater fitness. But is this the whole story.
   這種長期的系統(tǒng)變化說明自然選擇的作用，并表明女性骨骼的特性較大的適應性。但是，情況完全是這樣的嗎？