求解句子翻译，看不懂

Darwin held that many more individuals are produced than can find food and survive into adulthood.

answer is: Members of a species are forced to struggle for survival because many more individuals are born than can survive until the age of reproduction.

这里的than can是什么意思？

Dwrwin held that more individuals are produced than individuals can find food....

因为than后面的主语individuals和前面的是同样的 所以被省略了

第二句同上