Final answer:
External fertilization in water protects eggs, increases genetic diversity, and requires rapid maturation of offspring for higher survival rates.
Step-by-step explanation:
External fertilization in an aquatic environment is beneficial because it protects the eggs from drying out. It also allows for a greater mixture of genes within a group, leading to higher genetic diversity and a greater chance of species survival in a hostile environment. Additionally, the presence of fertilized eggs and developing young in the water provides opportunities for predation, resulting in a loss of offspring. Therefore, many eggs must be produced to increase the chances of survival. The offspring produced through external fertilization must also mature rapidly to improve their survival rate.