演化

• Our galaxy is a continuously evolving system .
  我们的星系是一个不断演化的星系。
• Plants had gradually evolved along diverging and converging pathways .
  植物是沿着趋异和趋同两种途径逐渐演化的。
• This evolution has occurred chiefly as a response to increasing labor cost .
  这种演化主要是随劳力费用增加而引起的。
• During the early stages of planetary evolution they served to sweep the solar system .
  在行星演化的早期，他们用来清扫太阳系。
• These were the protoplanets from which the planets of the present developed .
  这些就是原行星，现在的行星正是从它们演化而来的。
• Evolution of stars of all masses takes place on a hydrodynamic time scale .
  各种质量的恒星的演化，均以流体力学的时间尺度进行。
• The dicotyledons diverged at an early stage of their evolution into two main groups .
  双子叶植物在演化的早期阶段就已分化为两大支派。
• The evolution of today's universe follows with very few missing links in the chain of reasoning .
  当前的宇宙演化的一套理论中有很少的未知环节。
• We are surely not unmindful of our debt to the great classical figures of cosmogony .
  我们无疑不会忘记我们从天体演化学经典大师们那里得到的教益。
• The introduction emphasized the thoroughly evolutionary nature of modern astrophysics .
  在绪论中业已强调，现代天体物理学是彻底的承认演化的科学。