* ActorAllusion: From the 3D movie, this wouldn't be [[WesternAnimation/IceAge the first time]] John Leguizamo played a prehistoric animal, although this time he's playing a bird. And not [[Film/SuperMarioBros the first time]] [[Film/IceAgeDawnOfTheDinosaurs he's been surrounded by dinosaurs]].
** Humorously enough, his Ice Age costar, Ray Romano was picked to host the Discovery Channel premier of "Walking With Beasts" in order to promote Ice Age.
* ExecutiveMeddling: For the ''Walking with Dinosaurs'' movie, 20th Century Fox decided to add voices to the dinosaurs to help kids get the film, but the decision was made really late in production to the point where there isn't even lip syncing. The majority of viewers disliked the change, as they found the voices annoying and distracting. The DVD thus contains a "Cretaceous cut", which cuts out all the voices.
* OrphanedReference: The 'Cretaceous Cut' (the dialog-free version) of The Movie leaves in a few gags that make no sense without dialog:
** In the theatrical cut, Alex explains some gorgosaurus stats to the viewer with close up shots and diagrams (and he keeps getting distracted by its tiny arms). The visuals for this scene are left in the Cretaceous Cut.
** The film gets inexplicably re-wound when Patchi falls in the river (originally, Alex questions patchi's claim of diving in to save Jennifer)
** There is a close up of one of the knocked-out gorgosaurus teeth (which becomes the fossil in the present day scenes)
** The closing credits pop music starts to fade in and is interrupted by the gorgosaurus fourth wall break, but the actual credits with that song have been cut.
* WhatCouldHaveBeen:
** ''[[StockDinosaursTrueDinosaurs Baryonyx]]'' and ''Cetiosaurus'' were to appear in the main series, but they were replaced with ''[[StockDinosaursTrueDinosaurs Utahraptor]]'' and scrapped entirely, respectively.
** The ''Sea Monsters'' book describes a number of scenes that didn't make it into the series, such as the female [[UsefulNotes/PrehistoricLifeNonDinosaurianReptiles nothosaurs]] leaving their eggs on the beach at night (there is also a picture of Nigel inspecting those eggs, meaning it was filmed) and Nigel meeting the utterly bizarre [[http://en.wikipedia.org/wiki/Thalassocnus aquatic ground sloth]] ''[[UsefulNotes/PrehistoricLifeMammals Thalassocnus]]'' before going to look for the shark ''[[UsefulNotes/PrehistoricLifeOtherExtinctCreatures C. megalodon]]''.
** Originally ''Walking With Beasts'' was going to air first (the idea being that the trilogy would be moving backwards through time), but they only recieved enough money for a show about dinosaurs, and they made ''Walking With Dinosaurs''.
** Among the proposed episode ideas for ''WWB'' was one based around the Riversleigh fossil site from Australia. They chose to abandon it, as they already had enough stories planned.
*** For people wondering, such episode [[http://www.create.unsw.edu.au/research/files/Archer%20et%20al%20%281989%29%20Fossil%20Mammals%20of%20Riversleigh,%20Northwestern%20Queensland.PDF could have featured]] diprotodonts, thylacines, a ''Gastornis''-like bird (''Bullockornis''), running crocodiles and a python (since then included into ''Morelia'', but hard to believe they would pass the chance to drop the original name ''[[Creator/MontyPython Montypythonoides]]'').