Dr. Alan Grant: [finding egg shells] Oh my God. Do you know what this is? This is a dinosaur egg. The dinosaurs are breeding.
Tim: But Grandpa said all the dinosaurs were girls.
Dr. Alan Grant: Amphibian DNA.
Lex: What's that?
Dr. Alan Grant: Well, on the tour, the film said they used frog DNA to fill in the gene sequence gaps. They mutated the dinosaur genetic code and blended it with that of a frog's. Now, some West African frogs have been known to spontaneously change sex from male to female in a single sex environment. Malcolm was right. Look... [we see a trail of baby dinosaur footprints]
Dr. Alan Grant: Life found a way.