On the other hand, fish eggs develop outside the mother's body, and the entire process from insemination to completion of embryonic development takes only two days, giving fish advantages such as rapid growth and short generational cycles.
相對地，魚類屬於體外孵化，而且從受精到發育完成只需要短短兩天的時間，具有生長迅速、世代週期短等優點。