In 1978, American paleontologists John R. Horner (1946–) and Bob Makela discovered the fossilized remains of what would subsequently be called Maiasaura, or “good mother lizard,” in Montana. This was the first known nest of baby dinosaurs, and indicated the young had been cared for by adult dinosaurs. Starting in 1979, and working into the 1980s, Horner uncovered evidence of herding behavior in the dinosaurs, as well as nesting grounds, providing new insights into the social behavior of these dinosaurs. The herd was estimated to have been almost 10,000 dinosaurs strong.

Currently, John R. Horner is the regents’ professor and curator of paleontology for the Museum of the Rockies at Montana State University in Bozeman, Montana. He is one of the most famous North American paleontologists, known for his dinosaur fossil discoveries and for being the consultant for Hollywood’s Jurassic Park films.