Tim Murphy is Lex Murphy's brother and John Hammond's grandson. In the novel, he is described as a bespectacled boy of about eleven who has an interest in dinosaurs and computers. His quick thinking and encyclopedic knowledge of dinosaurs aid the group several times, and he is instrumental in discovering that dinosaurs have escaped the island, as well as regaining the means to warn the mainland. Later, Tim's ingenuity and technical knowledge allow him to navigate the park's computer systems and to reactivate the physical security systems before the "Velociraptors" gain access to the visitor's lodge. His expertise regarding dinosaurs rivals Grant's, and is superior to that of Dr. Wu, the scientist who created the dinosaurs. Already familiar with his work before they meet, Tim almost immediately strikes up a friendship with Grant, who notes "it's hard not to like someone so interested in dinosaurs". Tim's father does not share his interest in paleontology, so the dinosaur-loving Grant forms an instant bond with Tim during their time in the park.