the survival of the fittest短语⁹⁰⁸⁸⁷⁺⁷ 基本例句 adj.适者生存 Species in Yangtze River are deprived of the opportunities of the survival of the fittest. As the result, idioplasmic quality becomes increasingly degraded. 刀鲚、凤鲚、鳗鲡和中华绒螯蟹是当前全江尚具渔汛的四个江海洄游品种，但其资源日趋稀少。 fabiao