{{Short description|Hypothetical species and thought experiment}} [[File:Dinosauroid.jpg|thumb|A model of the hypothetical dinosauroid, Dinosaur Museum, Dorchester|273x273px]] The '''dinosauroid''' is a hypothetical species created by Dale A. Russell in 1982. Russell theorized that if a dinosaur such as ''Stenonychosaurus'' had not perished in the Cretaceous–Paleogene extinction event, its descendants might have evolved to fill the same ecological niche as humans.<ref name=russell1982>{{Cite journal | last1 = Russell | first1 = D. A. | last2 = Séguin | first2 = R. | year = 1982 | title = Reconstruction of the small Cretaceous theropod ''Stenonychosaurus inequalis'' and a hypothetical dinosauroid | url = https://archive.org/details/syllogeus37nati | journal = Syllogeus | volume = 37 | pages = 1–43 }}</ref> While the theory has been met with criticism from other scientists, the dinosauroid has been featured widely in books<ref>{{Cite book|title=The New Dinosaurs|last=Dixon|first=Dougal|publisher=Salem House|year=1988|isbn=978-0881623017|page=111 |access-date=17 June 2021|url-access=registration|url=https://archive.org/details/newdinosaursalte0000dixo}}</ref><ref>{{cite book |last1=Cranfield |first1=Ingrid |title=The Illustrated Directory of Dinosaurs and Other Prehistoric Creatures |date=2000 |publisher=Salamander Books |isbn=1-55267-119-4 |page=44 |url=https://books.google.com/books?id=VOAvE4UZTuwC |access-date=29 June 2021}}</ref><ref>{{cite book |last1=Lambert |first1=David |title=The Ultimate Dinosaur Book |date=2000 |publisher=Dorling Kindersley Publishing |isbn=0789476207 |url=https://books.google.com/books?id=AngsAQAACAAJ |access-date=17 June 2021}}</ref> and documentaries<ref>{{cite episode |title=Troodon: Portrait of a Killer |series=Paleoworld |season=2 |number=13 |date=1995 |network=Discovery Channel}}</ref><ref>{{cite web |last=Naish |first=Darren |date=26 May 2023 |title=My Own Personal Dinosauroid |website=Tetrapod Zoology |url=https://tetzoo.com/blog/2023/5/26/my-own-personal-dinosauroid}}</ref> since the theory's inception.
==Theory== In 1982, Dale A. Russell, then curator of vertebrate fossils at the Canadian Museum of Nature in Ottawa, conjectured a possible evolutionary path for ''Stenonychosaurus'', if it had not perished in the Cretaceous–Paleogene extinction event, suggesting that it could have evolved into intelligent beings similar in body plan to humans. Over geologic time, Russell noted that there had been a steady increase in the encephalization quotient or EQ (the relative brain weight when compared to other species with the same body weight) among the dinosaurs. Russell had discovered the first Troodontid skull, and noted that, while its EQ was low compared to humans, it was six times higher than that of other dinosaurs. Russell suggested that if the trend in ''Stenonychosaurus'' evolution had continued to the present, its brain case could by now measure 1,100 cm<sup>3</sup>, comparable to that of a human.<ref name=russell1982/>
Troodontids had semi-manipulative fingers, able to grasp and hold objects to a certain degree, and binocular vision.<ref name=russell1982/> Russell proposed that his dinosauroid, like members of the troodontid family, would have had large eyes and three fingers on each hand, one of which would have been partially opposed. Russell also speculated that the dinosauroid would have had a toothless beak. As with most modern reptiles (and birds), he conceived of its genitalia as internal. Russell speculated that it would have required a navel, as a placenta aids the development of a large brain case. However, it would not have possessed mammary glands, and would have fed its young, as some birds do, on regurgitated food. He speculated that its language would have sounded somewhat like bird song.<ref name=russell1982/><ref name=naish>{{cite web |last=Naish |first=Darren |date=2 November 2006 |title=Dinosauroids revisited |website=Darren Naish: Tetrapod Zoology |url=https://darrennaish.blogspot.com/2006/11/dinosauroids-revisited.html |access-date=23 April 2011}}</ref>
[[File:Stenonychosaurus head neck NHM.jpg|thumb|upright|Head and neck of Dale Russell and Ron Seguin's ''Stenonychosaurus'' sculpture, Natural History Museum, London]] Reflecting on the dinosauroid theory, Russell said in an interview in 2000;
{{Quote | style=font-size:100% |"The 'dinosauroid' was a thought experiment, based on an observable, general trend toward larger relative brain size in terrestrial vertebrates through geologic time, and the energetic efficiency of an upright posture in slow-moving, bipedal animals. It seems to me that such speculation remains acceptable, particularly if directed toward non-anthropoid anatomical configurations. However, I very nearly decided not to publish the exercise because of the damaging effects it might have had on the credibility of my work in general. Most people remained polite, although there were hostile reactions from those with 'ultra-quantitative' and 'ultra-intuitive' world views."<ref>{{cite magazine |last1=Black |first1=Riley |title=Troodon sapiens?: Thoughts on the "Dinosauroid" |magazine=Wired |date=23 October 2007 |url=https://www.wired.com/2007/10/troodon-sapiens-thoughts-on-the-dinosauroid/ |access-date=17 June 2021}}</ref> }}
===Sculpture=== Dale Russell worked in collaboration with taxidermist and artist Ron Seguin to create models of both a ''Stenonychosaurus'' and the fictional dinosauroid. While the model of ''Stenonychosaurus'' was constructed to reflect the biology of ''Stenonychosaurus'' as accurately as possible, the dinosauroid was wholly fabricated. The models were made in tandem, the ''Stenonychosaurus'' model taking about seven months to construct and the dinosauroid model taking about three and a half months to construct. The two models were built using similar techniques, built up over a skeleton of the creature, the final sculpt then being recast in fiberglass and filled with sand.<ref name=russell1982/>
==Reception== left|thumb|upright|Illustration of the original dinosauroid design Russell's thought experiment has been met with criticism from other paleontologists since the 1980s, many of whom point out that his Dinosauroid is overly anthropomorphic. Gregory S. Paul (1988) and Thomas R. Holtz, Jr., consider it "suspiciously human" and Darren Naish has argued that a large-brained, highly intelligent troodontid would retain a more standard theropod body plan, with a horizontal posture and long tail, and would probably manipulate objects with the snout and feet in the manner of a bird, rather than with human-like "hands".<ref name=naish/>
As Darren Naish explained in a 2012 Scientific American article on the subject of the dinosauroid,
{{Quote | style=font-size:100% |"The reason that we humans have the body shape that we do is not – I think – because it's the 'best' body shape for a smart, big-brained biped to have, it is instead the result of our specific lineage's evolutionary history. Given that, so far as we know, the humanoid body shape has evolved just once, we simply have no way of knowing whether it's a particularly 'good' morphology or not."<ref name=dinosauroids2012>{{cite web |last1=Naish |first1=Darren |date=27 October 2012 |title=Dinosauroids revisited, revisited |url=https://blogs.scientificamerican.com/tetrapod-zoology/dinosauroids-revisited-revisited/ |publisher=Scientific American. |access-date=17 June 2021}}</ref> }}
Some authors, however, had more favourable opinions on the dinosauroid, with David Norman remarking in the 1985 book ''The Illustrated Encyclopedia of Dinosaurs'' that “Such an idea is an obviously fanciful, though provocative thought.”<ref>{{cite book |last1=Norman |first1=David |title=The Illustrated Encyclopedia of Dinosaurs |date=1985 |publisher=Salamander Books |isbn=1840652047 |page=55}}</ref>
The dinosauroid theory, along with the often repeated fact that Troodontids were the most intelligent dinosaurs, may have led to an overestimation of its intelligence among the general public; while ''Stenonychosaurus'' did have a larger brain to body ratio when compared to other theropod dinosaurs of its time, its intelligence was likely comparable to that of modern birds such as bustards and emus.<ref name=dinosauroids2012/>
==Modernisation== Since Russell's original work in the 1980s, alternate interpretations of intelligence in non-avian dinosaurs have been depicted in art. The collaborative work of Turkish artist C. M. Kosemen and Canadian comic book artist Simon Roy is a particularly notable example of a modern take on the dinosauroid concept. These art pieces from the late 2000s show dinosaurs with anatomy more reflective of modern paleontological understanding and retain more of their ancestral, theropod features. These designs for a dinosauroid were based on Darren Naish's writings on Russell and Seguin's original.<ref name=Kosemen2009>{{cite web |last1=Kosemen |first1=C. M. |title=A World of Dinosauroids |url=http://www.cmkosemen.com/dinosauroids.html |date=2008 |access-date=24 September 2023}}</ref>
Kosemen and Roy's work expands upon the original concept by creating a wide range of different dinosauroid species and placing them inside of an entirely speculative ecosystem in a world without the Cretaceous–Paleogene extinction. These new dinosauroids are more inspired by birds and their tool use capability, with some inspiration from early hunter-gatherer societies as well.<ref name=Kosemen2009/>
==See also== *''The New Dinosaurs'' * Silurian hypothesis
==Further reading== * {{cite journal |last1=Naish |first1=Darren |last2=Tattersdill |first2=Will |date=17 May 2021 |title=Art, anatomy, and the stars: Russell and Séguin’s dinosauroid<sup>1</sup> |journal=Canadian Journal of Earth Sciences |volume=58 |issue=9 |pages=968-979 |url=https://cdnsciencepub.com/doi/full/10.1139/cjes-2020-0172}}
==References== {{Reflist}}
Category:Anthropomorphic dinosaurs Category:Speculative evolution Category:Thought experiments Category:Anthropomorphic reptiles Category:Fictional reptilians Category:Fictional species and races