The more fit a parent is, the more chances it will have to reproduce by being in the parent population multiple times.

亲本越适合，在亲本种群中出现的次数就会多，因而就会有更多机会繁殖下去。

youdao

Bears reproduce slowly, he says, so killing even a few could have large repercussions on the state's population of black, brown and grizzly bears.

他说，熊繁殖很缓慢，所以即使只杀掉很少的熊都会对该州黑熊、棕熊和灰熊的数量产生很大的影响。

youdao

Taking only this uncertainty of ability to reproduce into account, extinction is unlikely if the number of individuals in a population is above about 50 and the population is growing.

只考虑这些不确定的繁殖能力，灭绝不太可能如果个体的数字在一个种群数量超过50并且种群数量在增长。

youdao

There is no way that the shrunken generation of the 1990s can reproduce enough to stabilize the population.

WSJ: A Lost Opportunity to Save Russia