 At the visitor center , the group learns that the cloning was accomplished by extracting dinosaur DNA from mosquitoes that had been preserved in amber . DNA from frogs was used to fill in gaps in the dinosaur genomes . To prevent breeding , all the dinosaurs were made female . Malcolm scoffs at the idea of such controlled breeding , declaring it impossible . The crew witness the birth of a baby raptor and visit the raptor enclosure . Grant , Sattler , and Malcolm have reservations about the idea of resurrecting dinosaurs , but Hammond and Gennaro dismiss their fears . 
