At the heart of Jurassic Park, currently playing in Chicago in a new 3-D version, is a modest Chekhovian comedy about a longtime bachelor learning to accept the responsibilities of marriage and fatherhood. The bachelor, Dr. Alan Grant (Sam Neill), is a paleontologist who thinks he has it all: a dream job, a beautiful young girlfriend (Laura Dern), and, most importantly, his liberty. He travels extensively for his work, and since he’s often at the mercy of his grants, he can be pulled away to a new place at any time. He believes, like so many of us, that behaving a certain way will keep him young. Consider how he engages a preteen boy in his first scene, knowing how to appeal to his imagination and how to scare him. In a sense, being a paleontologist has made him the cool big brother every kid wants to have.