How does the author use foreshadowing in Dark Life: Book 1?

When Ty points out to Doc that the prisoners cannot have developed gifts unless they grew up under the sea as children, Doc insists that they may have developed abilities due to the water pressure. Although Ty isn't yet aware of it, he has actually come close to unraveling the secret behind Seablite and the doctor's involvement with it. The Seablite Gang actually have grown up under the sea, as they were sent to Seablite as children. Ty's comments here foreshadow the revelations to come.