The paleontologist who served as a technical adviser on Jurassic Park and helped inspire Alan Grant is Jack Horner.
Horner is an American paleontologist best known for research into dinosaur growth, nesting, and parental care. With Bob Makela, he described Maiasaura, a dinosaur whose fossil evidence helped establish that at least some non-avian dinosaurs cared for their young. That scientific work made him a natural adviser for a film series concerned with dinosaur behavior.
Horner served as technical adviser for the first five Jurassic Park films. Michael Crichton also drew on Horner when creating Alan Grant, although Grant is not a literal portrait of him. Grant’s fictional achievements, including work associated with Maiasaura, combine elements linked to Horner and Makela; the character has also been compared with Philip J. Currie.
Horner’s film influence extended beyond scientific consultation. He advocated treating dinosaur behavior as an evidence-based question, while the movies sometimes dramatized or simplified scientific debates. That distinction explains why the correct answer is Horner rather than another prominent dinosaur researcher such as Robert Bakker or John Ostrom.