The calves have about a 20 % mortality rate , so mating with bigger females could increase a male 's chance of reproductive success by siring larger , hardier offspring , pack says .
亚当包说雄性有20%的死亡率,因此与强壮的雌性结合可能增加雄性成功产强壮后代的几率。
Yet corals may be hardier than biologists have thought .
但是珊瑚也许比生物学家想得要更坚强。
Hardier creatures soon face another threat : people .
命硬的动物很快还会面临来自人类的威胁。
Theoretically , experiments with genes that confer resistance to disease or herbicides could create hardier weeds .
从理论上说,用含有抗病或抗除草剂的基因进行试验,可能产生更难于对付的杂草。
Maybe if I were a hardier person , little details likethat wouldn 't trouble me .