Final answer:
The author suggests that predators can harm animals and that an animal's shell helps protect it.
Step-by-step explanation:
The author suggests to the reader that predators can harm some animals and an animal's shell helps protect it. The sentence mentions that the shells save the animals from storms or predators such as starfish, birds, and otters. This implies that predators are a threat to animals and that their shells serve as a defense mechanism.