Dinosaur Expedition Born Free is a TV Series made by Tsuburaya Productions.
The show was the first in the Tsuburaya Dinosaur Trilogy and because Tsuburaya was filming Aztecizer, they could not have the show in Live action. Japan Sunrise did the animation. Paleontologist Ikuo Kobata criticized Tsuburaya for using costumes with the "Godzilla" posture, so Tsuburaya used stop-motion to have accurate dinosaurs.
A main inspiration for creating the series was the discovery of Taniwhasaurus (Ezo Mikasa Ryu) in 1976. At the time they thought the moasasaur was a tyrannosaur which explains the inaccurate Ezomikasa Dragon.