Editing Walking with Dinosaurs (section)

==== Scientific errors ====
[[File:Acinonyx jubatus -Southern Namibia-8.jpg|left|thumb|A [[cheetah]] marking its territory through urination. ''Walking with Dinosaurs'' controversially depicted this behaviour in the [[pseudosuchia]]n ''[[Postosuchus]]''.]]
Although the academic response to ''Walking with Dinosaurs'' was largely positive, the series was criticised by some palaeontologists for its speculative storylines and the boldness of some of its claims, noting that some aspects presented as fact were very much speculative and possible to be challenged in the future.<ref name=":9" /> In the companion book of the series, Haines admitted that speculating about dinosaur behaviour in of itself is unscientific since the theories cannot be tested, but maintained that it "seems well worth trying to find out more about how [the dinosaurs] may have lived", using both science and reasoned speculation.<ref name=":11" /> A handful of decisions and sequences in the series came under particular palaeontological criticism.<ref name=":9" /> Several supposed errors identified in the first weeks after the series aired fizzled out after a while, as critics found points about which they disagreed with one another and were unable to definitively prove their views.<ref name=":10" /> Most of the errors or otherwise questionable decisions of ''Walking with Dinosaurs'' were not the fault of the production team since they worked based on the advice of their consultants.<ref name=":9" />

''New Blood'' shows a male ''[[Postosuchus]]'' urinating to mark a female's territory as his own after she is driven away from it. A number of critics pointed out that birds and crocodiles, the closest living relatives of the dinosaurs, do not urinate; they shed waste chemicals as more solid [[uric acid]]. However, Michael J. Benton, a consultant of the series, noted that nobody could prove that this was a real mistake: copious urination is the primitive state for tetrapods (seen in fish, amphibians, turtles, and mammals), and perhaps basal [[archosaur]]s did the same.<ref name=":10" /> ''New Blood'' also depicts ''[[Plateosaurus]]'' as a [[Quadrupedalism|quadruped]], but more recent studies suggest that it was an obligate [[Bipedalism|biped]] due to its inability to [[pronate]] its [[Manus (anatomy)|manus]].<ref>{{Cite journal |last=Mallison |first=Heinrich |date=July 2010 |title=The Digital Plateosaurus I: Body Mass, Mass Distribution, and Posture Assessed by Using CAD and CAE on a Digitally Mounted Complete Skeleton |url=https://palaeo-electronica.org/2010_2/198/index.html |journal=Palaeontologia Electronica |volume=13 |issue=2}}</ref>

''[[Diplodocus]]'' was reconstructed with mostly horizontal necks in ''Walking with Dinosaurs'', an idea consistent with what was thought of their biology at the time, and thus pushed by the palaeontological consultants of the series, but challenged by new research in 2009.<ref name=":9" />

The pterosaur identified as ''Ornithocheirus'' in ''Giant of the Skies'' was actually based on fossils of the pterosaur ''[[Tropeognathus]]'', the two having been considered synonyms by David Unwin, one of the consulting palaeontologists.<ref name=":9" /> Additionally, it is depicted as far larger than it actually was. In the companion book, it was claimed that several large bone fragments from the [[Romualdo Formation]] of Brazil possibly indicate that ''Ornithocheirus'' may have had a wingspan reaching almost 12 metres and a weight of a hundred kilograms, making it one of the largest known pterosaurs.<ref>Haines, T., 1999, ''"Walking with Dinosaurs": A Natural History'', BBC Books, p. 158</ref> However, the largest definite ''Tropeognathus'' specimens described at the time measured {{convert|6|m|ft|sp=us}}, in terms of wingspan.<ref name="wellnhofferencyclo">Wellnhofer, P. (1991). ''The Illustrated Encyclopedia of Pterosaurs''. New York: Barnes and Noble Books. pp. 124. {{ISBN|0-7607-0154-7}}.</ref> The specimens which the producers of the program used to justify such a large size estimate were described in 2012 (with the designation MN 6594-V) and were under study by Dave Martill and David Unwin at the time of the production of the series. The final description of the remains found a maximum estimated wingspan of {{convert|8.70|m|ft|sp=us}} for this large specimen.<ref name="kellneretal2013">{{Cite journal |last1=Kellner |first1=A. W. A. |last2=Campos |first2=D. A. |last3=Sayão |first3=J. M. |last4=Saraiva |first4=A. N. A. F. |last5=Rodrigues |first5=T. |last6=Oliveira |first6=G. |last7=Cruz |first7=L. A. |last8=Costa |first8=F. R. |last9=Silva |first9=H. P. |last10=Ferreira |first10=J. S. |year=2013 |title=The largest flying reptile from Gondwana: A new specimen of Tropeognathus cf. T. Mesembrinus Wellnhofer, 1987 (Pterodactyloidea, Anhangueridae) and other large pterosaurs from the Romualdo Formation, Lower Cretaceous, Brazil |journal=Anais da Academia Brasileira de Ciências |volume=85 |issue=1 |pages=113–135 |doi=10.1590/S0001-37652013000100009 |pmid=23538956 |doi-access=free}}</ref> Unwin stated that he did not believe the higher estimate used by the BBC was likely, and that the producers likely chose the highest possible estimate because it was more "spectacular."<ref name="dmlbrdeow2">{{Cite web | author=Bredow, H.P. | url=http://dml.cmnh.org/2000Apr/msg00446.html | title=Re: WWD non-dino questions | archive-url=https://web.archive.org/web/20160404084446/http://dml.cmnh.org/2000Apr/msg00446.html | archive-date=2016-04-04 | date=2000-04-18}}</ref> Another famously "super-sized" animal in ''Walking with Dinosaurs'' is the pliosaur ''[[Liopleurodon]]'', described as reaching lengths of 25 metres in the series (but in reality probably only reaching 6.4 metres); the extreme size was based on fragmentary specimens, and the estimate was at the time justifiable extrapolation provided by some of the consultants, who pushed it as scientifically supported.<ref name=":9" />