In some official sources, the elderly Styracosaurus Eema is revealed to be one hundred years old, while Baylene, the Brachiosaurus, is said to be in her sixties.
The attraction called Dinosaur (previously called Countdown to Extinction) at Disney's Animal Kingdom Theme Park was originally to be created/opened at the same time as the movie's release as part of the company's "synchronicity" between branches of the WDC, but due to the overwhelming technology development required to begin production, the film's opening was delayed. Even though it was started after the film was in-production, the theme park ride opened first (by almost 18 months) before the movie's release; hence, the ride's name change later.
The elderly Brachiosaurus named Baylene was initially meant to be a much younger male Brachiosaurus named Sorbus who was described by the makers as a sort of Chris Farley-like character who had a fear of heights and so kept his head close to the ground. The character was revised to become Baylene, who, according to her official background story, was the last of a group of elderly Brachiosaurus.
The movie takes place in prehistoric North America, yet the Carnotaurs, the main antagonists were actually South American dinosaurs. The characters do claim that they haven't been seen "this far up north" before, however this doesn't rectify the mistake, since North and South America weren't connected back then. The Carnotaurs would have had to swim through the sea to reach North America, which would have been impossible.
When Baylene is running to jump in the lake at the Nesting Grounds, she is shown to run right near the water's edge. After three shots, she is back where she started to run.