第三章的标题是“生存竞争” (The Struggle for Existence)，在物种起源这个基准之下，何处竞争最为严酷？
2
?生存斗争
我们现在要更加详细一点讨论生存斗争（the struggle for existence）的细节。在我以后的工作中会考察这一主题，因为一个长的多的该主题是很值得而为的。
双语例句
1
Thestruggleforexistence occurs not in fights, but in the competition for limited feeding areas and for the occupancy of areas free from meat-eating animals.
为生存而进行的斗争不是发生在战斗中，而是在争夺有限的觅食区和占用没有肉食动物的区域的竞争中。
2
Thestruggleforexistence occurs not in such fights, but in the competition for limited feeding areas and for the occupancy of areas free from meat-eating animals.
生存的斗争并不发生在这种争斗中，而是为了争夺有限的摄食区域，以及为了争夺没有食肉动物的领地。
3
Those individuals who possess characteristics that provide them with an advantage in thestruggleforexistence are more likely to survive and contribute their genes to the next generation.