The game was planned for the Nintendo 64, and much of its DNA still exists in Star Fox Adventures.
Nintendo historian “Forest of Illusion” shared his find online. “Dinosaur Planet” is therefore fully playable and in a very advanced stage of development, they say. Still, it doesn’t run perfectly on emulators.
The build seems to come from the time after Nintendo already decided to integrate elements of “Star Fox”.
“Forest of Illusion” bought the build of “Dinosaur Planet” from the end of 2000 from a collector in Sweden. Attached you can see gameplay material from the discontinued project, which would certainly have been a hit for the Nintendo 64 of the time.