The Jurassic Park franchise grossed more than $2 billion at the box office over the span of three movies and eight years, with the original film ranking in the top 20 American box-office performances of all time. On Friday, the franchise roars again with Jurassic World, a fourth installment that imagines how things might turn out if a dinosaur theme park attempted to attract visitors by creating a genetically modified hybrid dinosaur. (By all appearances, the answer is "not well.")
In 2015, we need genetic mutants and modern technology to amp up the drama. But in 1939, there was plenty of drama in the sheer possibility of seeing dinosaur fossils in a museum. That year, New York City’s American Museum of Natural History debuted the largest fossil exhibit in the world, consisting of 200 specimens covering a time period of 200 million years.
Much of the collection came thanks to the paleontologist Barnum Brown, who had been excavating fossils since the 1890s. Among Brown’s treasures were a 66-ft. brontosaurus discovered in Wyoming and a nodosaurus, “resembling a huge horned toad,” originally found in 10,000 pieces near Billings, Mont.
Decidedly absent from the momentous exhibition? Indominus rex, Jurassic World’s violent hybrid of four real-life dinosaur species. Let’s hope that one remains a figment of Hollywood’s imagination.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter @lizabethronk.