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	{{otheruses}}
	{{Taxobox
	\| name = Dinosaurs
	\| fossil_range = {{fossil range\|230.0\|65.5}}] – ]<br /> <small>(excluding ])</small>
	\| image = field_dinos_2.jpg
	\| image_width = 260px
	\| image_caption = Mounted skeletons of '']'' (left) and '']'' (right) at the ].
	\| regnum = ]ia
	\| phylum = ]
	\| classis = ]
	\| subclassis = ]a
	\| infraclassis = ]
	\| superordo = '''Dinosauria''' ]
	\| superordo_authority = ], 1842
	\| subdivision_ranks = Orders & Suborders
	\| subdivision = <div>
	* ''']'''
	** ]
	** ]
	* ''']'''
	** ]
	** ]
	</div>
	}}
	'''Dinosaurs''' were ] animals that dominated ] ]s for over 160 million years, first appearing approximately 230 ]. At the end of the ] ], 65 million years ago, a catastrophic ] ended the dominance of dinosaurs on land. One group of dinosaurs is known to have survived to the present day: ] believe modern ]s are direct descendants of ] dinosaurs.

	Since the first dinosaur ]s were recognized in the early nineteenth century, mounted dinosaur skeletons have become major attractions at museums around the world. Dinosaurs have become a part of world culture and remain consistently popular among children and adults. They have been featured in best-selling books and films, and new discoveries are regularly covered by the ].

	The term ''dinosaur'' is sometimes used informally to describe other prehistoric reptiles, such as the ] '']'', the winged ]s, and the aquatic ]s, ]s and ]s, although none of these were dinosaurs.

	==What is a dinosaur?==
	===Definition===
	]'' ] at the ] in New York City.]]
	The ] '''Dinosauria''' was formally named in 1842 by ] ] ], who used it to refer to the "distinct tribe or sub-order of Saurian Reptiles" that were then being recognized in England and around the world.<ref>Owen, R. (1842). "Report on British Fossil Reptiles." Part II. Report of the British Association for the Advancement of Science, Plymouth, England.</ref> The term is derived from the ] words δεινός (''deinos'' meaning "terrible", "fearsome", or "formidable") and σαύρα (''saura'' meaning "lizard" or "reptile"). Though the taxonomic name has often been interpreted as a reference to dinosaurs' teeth, claws, and other fearsome characteristics, Owen intended it merely to evoke their size and majesty.<ref name=FBS97>Farlow, J.O., and Brett-Surman, M.K. (1997). Preface. In: Farlow, J.O., and Brett-Surman, M.K. (eds.). ''The Complete Dinosaur.'' Indiana University Press: Bloomington and Indianapolis, ix-xi. ISBN 0-253-33349-0</ref>

	Dinosaurs were an extremely varied group of animals; according to a 2006 study, over 500 dinosaur genera have been identified with certainty so far, and the total number of genera preserved in the fossil record has been estimated at around 1,850, nearly 75% of which remain to be discovered.<ref>Wang, S.C., and Dodson, P. (2006). Estimating the Diversity of Dinosaurs. Proceedings of the National Academy of Sciences USA 103:37, pp. 13601–13605. </ref> An earlier study predicted that about 3,400 dinosaur genera existed, including many which would not have been preserved in the fossil record.<ref name="russell1995">Russell, Dale A. (1995). China and the lost worlds of the dinosaurian era. ''Historical Biology'' 10: 3-12.</ref> Some were ], others ]. Some dinosaurs were ]s, some were ]s, and others, such as '']'' and '']'', could walk just as easily on two or four legs. Regardless of body type, nearly all known dinosaurs were well-adapted for a predominantly terrestrial, rather than aquatic or aerial, habitat.

	====Distinguishing features of dinosaurs====
	While recent discoveries have made it more difficult to present a universally agreed-upon list of dinosaurs' distinguishing features, nearly all dinosaurs discovered so far share certain modifications to the ancestral ]ian skeleton. Although some later groups of dinosaurs featured further modified versions of these traits, they are considered typical across Dinosauria; the earliest dinosaurs had them and passed them on to all their descendants. Such common structures across a taxonomic group are called ].

	Dinosaur synapomorphies include an elongated crest on the ], or upper arm bone, to accommodate the attachment of ] muscles; a shelf at the rear of the ], or main hip bone; a ], or shin bone, featuring a broad lower edge and a flange pointing out and to the rear; and an ascending projection on the ], one of the ankle bones, which secures it to the tibia.<ref name=MJB04>Benton, M.J. (2004). Origin and relationships of dinosaurs. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). ''The Dinosauria'' (second edition). University of California Press:Berkeley, 7–19. ISBN 0-520-24209-2.</ref>

	]'' was an "armored dinosaur" of the group ].]]
	A variety of other skeletal features were shared by many dinosaurs. However, because they were either common to other groups of ] or were not present in all early dinosaurs, these features are not considered to be synapomorphies. Such shared features include a ] skull bearing two pairs of holes in the temporal region; holes in the snout and lower jaw (two characteristics shared by other archosaurs); loss of the skull's postfrontal bone; a long neck incorporating an S-shaped curve;<ref name=TRHJ00>Holtz, Jr., T.R. (2000). Classification and evolution of the dinosaur groups. In: Paul, G.S. (ed.). ''The Scientific American Book of Dinosaurs.'' St. Martin's Press:New York, 140–168. ISBN 0-312-26226-4.</ref> an elongated ], or shoulder blade; forelimbs shorter and lighter than hind limbs, coupled to asymmetrical hands; a ] composed of three or more fused ]e; and an ], or hip socket, with a hole at the center of its inside surface.<ref name=LARB99>Langer, M.C., Abdala, F., Richter, M., and Benton, M.J. (1999). A sauropodomorph dinosaur from the Upper Triassic (Carnian) of southern Brazil. ''Comptes Rendus de l'Academie des Sciences, Paris: Sciences de la terre et des planètes'' '''329''':511–517.</ref>

	The open, or "perforate", hip joint described above had significant implications for dinosaur movement and behavior. Most notably, it allowed dinosaur hind limbs to be "underslung", or situated directly beneath the animals' bodies; this, in turn, allowed dinosaurs to stand erect in a manner similar to modern mammals, but distinct from most other reptiles, whose limbs sprawl out to either side.<ref name=MJB00>Benton, M.J. (2004). ''Vertebrate Paleontology'' (second edition). Blackwell Publishers:London, xii-452. ISBN 0-632-05614-2.</ref> Vertical limb configuration also enabled dinosaurs to breathe easily while moving, which likely permitted stamina and activity levels that surpassed ].

	====Phylogenetic definition====
	Under ], dinosaurs are usually defined as all descendants of the most recent common ancestor of '']'' and modern ].<ref name="padian&may1993">Padian, K., and May, C.L. (1993). "The earliest dinosaurs." pp. 379–381 in S.G. Lucas and M. Morales, eds., ''The Nonmarine Triassic''. Albuquerque: New Mexico Museum of Natural History and Science Bulletin 3.</ref> It has also been suggested that Dinosauria be defined as all the descendants of the most recent common ancestor of '']'' and '']'', because these were two of the three genera cited by Richard Owen when he recognized the Dinosauria.<ref name="olshevsky2000">Olshevsky, G. (2000). "An annotated checklist of dinosaur species by continent." ''Mesozoic Meanderings'', '''3''': 1–157</ref> They are divided into ] (''bird-hipped'') and ] (''lizard-hipped''), depending upon ] structure. Ornithischian dinosaurs had a four-pronged pelvic configuration, incorporating a caudally-directed (rear-pointing) ] bone with (most commonly) a forward-pointing process. By contrast, the pelvic structure of saurischian dinosaurs was three-pronged, and featured a pubis bone directed cranially, or forwards, only.<ref name=MJB00/> Ornithischia includes all ] sharing a more recent common ancestor with ''Triceratops'' than with Saurischia, while Saurischia includes those taxa sharing a more recent common ancestor with ''birds'' than with Ornithischia.

	]'' skeleton, ], ].]]
	There is an almost universal consensus among paleontologists that birds are the descendants of ] dinosaurs. Using the strict ] definition that all descendants of a single common ancestor are related, modern birds ''are'' dinosaurs and dinosaurs are, therefore, not extinct. Modern birds are classified by most paleontologists as belonging to the subgroup ], which are ], which are ], which are ]ns, which are dinosaurs.<ref name=KP04>Padian, K. (2004). Basal Avialae. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). ''The Dinosauria'' (second edition). University of California Press:Berkeley, 210–231. ISBN 0-520-24209-2.</ref>

	However, referring to birds as 'avian dinosaurs' and to all other dinosaurs as 'non-avian dinosaurs' is cumbersome. Birds are still referred to as birds, at least in popular usage and among ]s. It is also technically correct to refer to birds as a distinct group under the older ] system, which accepts ] taxa that exclude some descendants of a single common ancestor. Paleontologists mostly use ], which classifies birds as dinosaurs, but some biologists of the older generation do not.

	For clarity, this article will use 'dinosaur' as a synonym for 'non-avian dinosaur', and 'bird' as a synonym for 'avian dinosaur' (meaning any animal that evolved from the common ancestor of '']'' and modern birds). The term 'non-avian dinosaur' will be used for emphasis as needed.

	===Size===
	]''; human figures provide scale.]]

	While the evidence is incomplete, it is clear that, as a group, dinosaurs were large. Even by dinosaur standards, the ] were gigantic. For much of the dinosaur era, the smallest sauropods were larger than anything else in their habitat, and the largest were an ] more massive than anything else that has since walked the Earth. Giant prehistoric ]s such as the '']'' and the Columbian ] were dwarfed by the giant sauropods, and only a handful of modern aquatic animals approach or surpass them in size — most notably the ], which reaches up to 190,000 kg (209 tons) and over 30 m (100 ft) in length.

	Most dinosaurs, however, were much smaller than the giant sauropods. Current evidence suggests that dinosaur average size varied through the Triassic, early Jurassic, late Jurassic and Cretaceous periods.<ref> Working hypothesis for body size.</ref> According to paleontologist Bill Erickson, estimates of median dinosaur weight range from 500 kg to 5 ]s; a recent study of 63 dinosaur genera yielded an average weight greater than 850 kg — comparable to the weight of a grizzly bear — and a median weight of nearly 2 tons, or about as much as a giraffe. This contrasts sharply with the size of modern mammals; on average, mammals weigh only 863 grams, or about as much as a large rodent. The smallest dinosaur was bigger than two-thirds of all current mammals; the majority of dinosaurs were bigger than all but 2% of living mammals.<ref> Source of Erickson quote.</ref>

	====Largest and smallest dinosaurs====
	Only a tiny percentage of animals ever fossilize, and most of these remain buried in the earth. Few of the specimens that are recovered are complete skeletons, and impressions of skin and other soft tissues are rare. Rebuilding a complete skeleton by comparing the size and morphology of bones to those of similar, better-known species is an inexact art, and reconstructing the muscles and other organs of the living animal is, at best, a process of educated guesswork. As a result, scientists will probably never be certain of the ].

	]''.]]
	]''.]]
	The tallest and heaviest dinosaur known from good skeletons is '']'' (also known as '']''). Its remains were discovered in ] between 1907–12. Bones from multiple similarly-sized individuals were incorporated into the skeleton now mounted and on display at the ] of ];<ref name=EC68>Colbert, E.H. (1968). ''Men and Dinosaurs: The Search in Field and Laboratory.'' E. P. Dutton & Company:New York, vii + 283 p. ISBN 0140212884.</ref> this mount is 12 m (38 ft) tall, 22.5 m (74 ft) long, and would have belonged to an animal that weighed between 30,000–60,000 kg (33–66 ]s). The longest complete dinosaur is the 27 m (89 ft) long '']'', which was discovered in ] in the ] and displayed in ] ] in 1907.

	There were larger dinosaurs, but knowledge of them is based entirely on a small number of fragmentary fossils. Most of the largest ] specimens on record were all discovered in the 1970s or later, and include the massive '']'', which may have weighed 80,000–100,000 kg (88–121 tons); the longest, the 40 m (130 ft) long '']''; and the tallest, the 18 m (60 ft) '']'', which could have reached a sixth-floor window. The longest of them all may have been '']'', known only from a now lost partial vertebral ] described in 1878. Extrapolating from the illustration of this bone, the animal may have been 58 m (190 ft) long and weighed over 120,000 kg (132 tons),<ref name=KC06>{{cite book \|last=Carpenter \|first=Kenneth \|authorlink=Kenneth Carpenter \|year=2006 \|chapter=Biggest of the big: a critical re-evaluation of the mega-sauropod ''Amphicoelias fragillimus'' \|editors=Foster, John R.; and Lucas, Spencer G. (eds.) \|title=Paleontology and Geology of the Upper Jurassic Morrison Formation \|series=New Mexico Museum of Natural History and Science Bulletin, '''36''' \|publisher=New Mexico Museum of Natural History and Science \|location=Albuquerque, New Mexico \|pages=131-138 \|url=https://scientists.dmns.org/sites/kencarpenter/PDFs%20of%20publications/Amphicoelias.pdf \|format=pdf}}</ref> heavier than all known dinosaurs except possibly the poorly known '']'', which could have weighed 175,000–220,000 kg (193–243 tons). The largest known ] dinosaur was '']'', reaching a length of 16–18 meters (53–60 ft), and weighing in at 9 tons.<ref name=SMBM06>dal Sasso, C., Maganuco, S., Buffetaut, E., and Mendez, M.A. (2006). New information on the skull of the enigmatic theropod ''Spinosaurus'', with remarks on its sizes and affinities. ''Journal of Vertebrate Paleontology'' '''25'''(4):888–896.</ref> Other large meat-eaters included '']'', '']'', '']'' and '']''.

	Not including modern birds, the smallest dinosaurs known were about the size of a ] or a ]. The theropods '']'' and '']'' were both under 60 cm (2 ft) in length.

	===Behavior===
	]'' was discovered in 1978.]]

	Interpretations of dinosaur behavior are generally based on the pose of body fossils and their ], ]s of their ], and comparisons with modern animals in similar ]s. As such, the current understanding of dinosaur behavior relies on speculation, and will likely remain controversial for the foreseeable future. However, there is general agreement that some behaviors which are common in crocodiles and birds, dinosaurs' closest living relatives, were also common among dinosaurs.

	The first direct evidence of ]ing behavior was the 1878 discovery of 31 '']'' dinosaurs which were thought to have perished together in ], ], after they fell into a deep, flooded ] and drowned.<ref>Johan Yans, Jean Dejax, Denise Pons, Christian Dupuis, Philippe Taquet.(2005) Palaeontological and geodynamical implications of the palynological dating of the wealden facies sediments of Bernissart (Mons Basin, Belgium). ''C. R. Palevol 4 (2005)'' 135–150.</ref> Despite the deposition of those skeletons being now regarded as more gradual,<ref>Deposition of ''Iguanodon'' skeletons occurred in at least 3 different events.</ref> other, well supported, mass death sites were subsequently discovered. Those, along with multiple trackways, suggest that ] or ] behavior was common in many dinosaur species. Trackways of hundreds or even thousands of herbivores indicate that ] (hadrosaurids) may have moved in great herds, like the ] or the African ]. Sauropod tracks document that these animals traveled in groups composed of several different species, at least in ], England,<ref>Day, J.J. and Upchurch, P. (2002). Sauropod Trackways, Evolution, and Behavior. ''Science'' 296:1659. </ref> and others kept their young in the middle of the herd for defense according to trackways at Davenport Ranch, ]. Dinosaurs may have congregated in herds for defense, for ] purposes, or to provide protection for their young.
	], ].]]
	] 1978 discovery of a '']'' ("good mother dinosaur") ]ing ground in ] demonstrated that parental care continued long after birth among the ]s.<ref>Horner J.R., Makela R., 1979. Nest of Juveniles Provides Evidence of Family-Structure Among Dinosaurs, ''Nature'' 282 (5736): 296–298</ref> There is also evidence that other Cretaceous-era dinosaurs, like the ]n sauropod '']'' (1997 discovery), had similar nesting behaviors, and that the animals congregated in huge nesting colonies like those of ]s. The ]n ]n '']'' was discovered in a ]-like ]ing position in 1993, which may mean it was covered with an insulating layer of feathers that kept the ] warm.<ref> ] nests or ]?</ref> Trackways have also confirmed parental behavior among sauropods and ornithopods from the ] in northwestern ].<ref> Footprints show maternal instinct after leaving the nest.</ref> Nests and eggs have been found for most major groups of dinosaurs, and it appears likely that dinosaurs communicated with their young, in a manner similar to modern birds and crocodiles.

	]'', herbivorous ] dinosaurs from the late Cretaceous fauna of North America.]]
	The ] and frills of some dinosaurs, like the ]ns, ]s and ]s, may have been too fragile to be used for active defense, so they were likely used for sexual or aggressive displays, though little is known about dinosaur mating and ]. The nature of dinosaur ] also remains enigmatic, and is an active area of research. For example, recent evidence suggests that the hollow crests of the lambeosaurines may have functioned as ]s used for a wide range of ]s.

	From a behavioral standpoint, one of the most valuable dinosaur fossils was discovered in the ] in 1971. It included a '']'' attacking a '']'',<ref> The discovery of two ] dinosaurs entangled together proved many theories.</ref> proving that dinosaurs did indeed attack and eat each other. While ]istic behavior among ]s is no surprise,<ref> The mystery of a dinosaur ].</ref> this too was confirmed by tooth marks from Madagascar in 2003.<ref>Rogers, R.R., Krause, D.W. and Rogers, K.C. (2003). Cannibalism in the Madagascan dinosaur Majungatholus atopus. ''Nature'' 422:515-518..</ref>

	Based on current fossil evidence only a single dinosaur, '']'', shows adaptations suggestive of a partially ] lifestyle, and relatively few were ], most notably the primitive ] such as ]. Since the later mammalian radiation in the ] produced numerous burrowing and tree-climbing species, e.g., ]s and ]s, the lack of evidence for a similar radiation of species among the dinosaurs is somewhat surprising. Because most dinosaur species seem to have relied on land-based locomotion, a good understanding of how dinosaurs moved on the ground is key to models of dinosaur behavior; the science of ], in particular, has provided significant insight in this area. For example, studies of the forces exerted by muscles and gravity on dinosaurs' skeletal structure have investigated how fast dinosaurs could run,<ref> Gait and his formula on estimating a dinosaur's speed.</ref><ref> More on Gait and his speed calculations.</ref> whether ]s could create ]s via ]-like tail snapping,<ref>Douglas, K. and Young, S. (1998). The dinosaur detectives. ''New Scientist'' 2130:24. .</ref> whether giant theropods had to slow down when rushing for food to avoid fatal injuries,<ref>Hecht, J. (1998). The deadly dinos that took a dive. ''New Scientist'' 2130. .</ref> and whether sauropods could float.<ref>Henderson, D.M. (2003). Effects of stomach stones on the buoyancy and equilibrium of a floating crocodilian: A computational analysis. ''Canadian Journal of Zoology'' 81:1346–1357. .</ref>

	==Evolution of dinosaurs==
	Dinosaurs diverged from their ] ancestors approximately 230 million years ago during the Middle to Late ] period, roughly 20 million years after the ] wiped out an estimated 95% of all ].<ref>Citation for Permian/Triassic extinction event, percentage of animal species that went extinct. </ref><ref>Another citation for P/T event data. </ref> ] of fossils from the early dinosaur ] '']'' establishes its presence in the fossil record at this time. Paleontologists believe ''Eoraptor'' resembles the ] of all dinosaurs;<ref>Hayward, T. (1997). The First Dinosaurs. ''Dinosaur Cards''. Orbis Publishing Ltd. D36040612.</ref> if this is true, its traits suggest that the first dinosaurs were small, bipedal predators.<ref>Sereno, P.C., C.A. Forster, R.R. Rogers, and A.M. Monetta. 1993. Primitive dinosaur skeleton from Argentina and the early evolution of Dinosauria. Nature 361:64–66.</ref> The discovery of primitive, dinosaur-like ornithodirans such as '']'' and '']'' in ] ] strata supports this view; analysis of recovered fossils suggests that these animals were indeed small, bipedal predators.

	The first few lines of primitive dinosaurs ] through the rest of the Triassic period; dinosaur species quickly evolved the specialized features and range of sizes needed to exploit nearly every terrestrial ]. During the period of dinosaur predominance, which encompassed the ensuing ] and ] periods, nearly every known land animal larger than 1 meter in length was a dinosaur.

	The ], which occurred approximately 65 million years ago at the end of the Cretaceous period, caused the extinction of all dinosaurs except for the line that had already given rise to the first birds. Other ] species related to the dinosaurs also survived the event.

	==Study of dinosaurs==
	Knowledge about dinosaurs is derived from a variety of fossil and non-fossil records, including ]ized ]s, ], ]s, ]s, ]s, impressions of skin, ] and ]s.<ref name="softtissue">Dal Sasso, C. and Signore, M. (1998). Exceptional soft-tissue preservation in a theropod dinosaur from Italy. ''Nature'' 292:383–387. </ref><ref>Schweitzer, M.H., Wittmeyer, J.L. and Horner, J.R. (2005). Soft-Tissue Vessels and Cellular Preservation in Tyrannosaurus rex. ''Science'' 307:1952–1955. </ref> Many fields of study contribute to our understanding of dinosaurs, including ], ], ], and the ] (of which ] is a sub-discipline).

	Dinosaur remains have been found on every continent on Earth, including ]. Numerous fossils of identical and closely related dinosaur species have been found on different continents, in accordance with the generally-accepted theory that all land masses were once connected in a super-continent called ].<ref>Evans, J. (1998). ''Ultimate Visual Dictionary - 1998 Edition''. Dorling Kindersley Books. 66–69. ISBN 1-871854-00-8.</ref>

	===The "dinosaur renaissance"===
	{{main\|Dinosaur renaissance}}
	The field of dinosaur research has enjoyed a surge in activity that began in the 1970s and is ongoing. This was triggered, in part, by ]'s discovery of '']'', an active, vicious ] that may have been ], in marked contrast to the then-prevailing image of dinosaurs as sluggish and ]. ], arguably the primary scientific discipline involved in dinosaur research, has become a global ]. Major new dinosaur discoveries have been made by paleontologists working in previously unexploited regions, including ], South America, ], ], and most significantly in ] (the amazingly well-preserved ] in ] have further consolidated the link between dinosaurs and their conjectured living descendants, modern birds). The widespread application of ], which rigorously analyzes the relationships between biological organisms, has also proved tremendously useful in ] dinosaurs. Cladistic analysis, among other modern techniques, helps to compensate for an often incomplete and fragmentary ].

	===Classification===
	{{main\|Dinosaur classification}}

	Dinosaurs (including birds) are ]s, like modern ]ns. Archosaurs' ] skulls have two holes, called ], located where the jaw muscles attach. Most reptiles (including birds) are diapsids; mammals, with only one temporal fenestra, are called ]s; and ]s, with no temporal fenestra, are ]s. Anatomically, dinosaurs share many other archosaur characteristics, including teeth that grow from sockets rather than as direct extensions of the jawbones. Within the archosaur group, dinosaurs are differentiated most noticeably by their gait. Dinosaur legs extend directly beneath the body, whereas the legs of lizards and crocodylians sprawl out to either side. All dinosaurs were land animals.

	Many other types of reptiles lived at the same time as the dinosaurs. Some of these are commonly, but incorrectly, thought of as dinosaurs, including ]s (which are not closely related to the dinosaurs) and ], which developed separately from reptilian ancestors in the late Triassic period.

	Collectively, dinosaurs are usually regarded as a ] or an unranked ]. They are divided into two ], the '']'' and the '']'', on the basis of their hip structure. Saurischians ('lizard-hipped', from the ] ''sauros'' (''σαυρος'') meaning 'lizard' and ''ischion'' (''ισχιον'') meaning 'hip joint') are dinosaurs that originally retained the hip structure of their ancestors. They include all the ] (bipedal ]s) and ] (long-necked ]s). Ornithischians ('bird-hipped', from the ] ''ornitheios'' (''ορνιθειος'') meaning 'of a bird' and ''ischion'' (''ισχιον'') meaning 'hip joint') is the other dinosaurian order, most of which were ]al herbivores. ('''NB:''' the terms "lizard hip" and "bird-hip" are misnomers — birds evolved from dinosaurs with "lizard hips".)

	<center><gallery>
	Image:Saurischia.png\|]n pelvis structure (left side)
	Image:Tyrannosaurus pelvis left.JPG\|'']'' pelvis (showing saurischian structure - left side)
	Image:Ornithischia.png\|]n pelvis structure (left side).
	Image:Edmontosaurus pelvis left.JPG\|'']'' pelvis (showing ornithischian structure - left side)
	</gallery></center>

	The following is a simplified classification of dinosaur families. A more detailed version can be found at ].

	The dagger (†) is used to indicate taxa that are ].

	===Order Saurischia===
	]'', an ostrich-like ] dinosaur.]]
	* †Infraorder ]ia
	* Suborder ]
	** †Superfamily ]
	** †Infraorder ]
	*** Family ]
	*** Family ]
	** Clade ]
	*** †Superfamily ]
	**** Family ]
	**** Family ]
	*** †Infraorder ]
	*** Clade ]
	**** †Superfamily ]
	**** †Infraorder ]
	**** †Infraorder ]
	**** †Infraorder ]
	**** †Infraorder ]
	***** Family ]
	***** Family ]
	]'' is an example of a ] dinosaur.]]
	* †Suborder ]
	** Infraorder ]
	*** Family ]
	*** Family ]
	*** Family ]
	** Infraorder ]
	*** Family ]
	*** Family ]
	*** Family ]
	*** Family ]
	*** Family ]
	*** Family ]
	*** Clade ]
	*** Clade ]
	**** Superfamily ]
	**** Family ]
	**** Family ]
	**** Superfamily ]

	=== †Order Ornithischia ===
	] dinosaurs and one ]. Far left: '']'', left: '']'', center background: '']'', center foreground: '']'', right: '']'', far right (small): '']'', far right (large) '']''.]]
	* Family ]
	* Suborder ]
	** Family ]
	** Infraorder ]
	** Infraorder ]
	*** Family ]
	*** Family ]
	* Suborder ]
	** Family ]
	** Infraorder ]
	*** Family ]
	*** Family ]
	*** Superfamily ]
	** Clade ]
	*** Infraorder ]
	*** Infraorder ]
	**** Family ]
	**** Family ]
	**** Family ]

	==Areas of debate==
	===Physiology===
	{{main\|Physiology of dinosaurs}}
	]'' skull and upper vertebral column, Palais de la Découverte, Paris.]]
	A vigorous debate on the subject of temperature regulation in dinosaurs has been ongoing since the 1960s. Originally, scientists broadly disagreed as to whether dinosaurs were capable of regulating their body temperatures at all. More recently, dinosaur ]y has become the consensus view, and debate has focused on the mechanisms of temperature regulation.

	After dinosaurs were discovered, paleontologists first posited that they were ]ic creatures: "terrible ]s" as their name suggests. This supposed cold-bloodedness implied that dinosaurs were relatively slow, sluggish organisms, comparable to modern reptiles, which need external sources of heat in order to regulate their body temperature. Dinosaur ectothermy remained a prevalent view until ], an early proponent of dinosaur endothermy, published an influential paper on the topic in 1968.

	Modern evidence indicates that dinosaurs thrived in cooler temperate climates, and that at least some dinosaur species must have regulated their body temperature by internal biological means (perhaps aided by the animals' bulk). Evidence of ]ism in dinosaurs includes the discovery of ] and ] (where they would have experienced a cold, dark six-month winter), the discovery of dinosaurs whose feathers may have provided regulatory insulation, and analysis of blood-vessel structures that are typical of endotherms within dinosaur bone. Skeletal structures suggest that theropods and other dinosaurs had active lifestyles better suited to an endothermic cardiovascular system, while sauropods exhibit fewer endothermic characteristics. It is certainly possible that some dinosaurs were endothermic while others were not. Scientific debate over the specifics continues.<ref>Parsons, K.M. (2001). ''Drawing Out Leviathan''. Indiana University Press. 22–48. ISBN 0-253-33937-5.</ref>

	Complicating the debate is the fact that warm-bloodedness can emerge based on more than one mechanism. Most discussions of dinosaur endothermy tend to compare them to average birds or mammals, which expend energy to elevate body temperature above that of the environment. Small birds and mammals also possess ], such as ], ], or ]s, which slows down heat loss. However, large mammals, such as elephants, face a different problem because of their relatively small ratio of surface area to volume (] principle). This ratio compares the volume of an animal with the area of its skin: as an animal gets bigger, its surface area increases more slowly than its volume. At a certain point, the amount of heat radiated away through the skin drops below the amount of heat produced inside the body, forcing animals to use additional methods to avoid overheating. In the case of elephants, they are hairless, and have large ears which increase their surface area, and have behavioral adaptations as well (such as using the trunk to spray water on themselves and mud wallowing). These behaviors increase cooling through evaporation.

	Large dinosaurs would presumably have had to deal with similar issues; their body size suggest they lost heat relatively slowly to the surrounding air, and so could have been what are called ], animals that are warmer than their environments through sheer size rather than through special adaptations like those of birds or mammals. However, so far this theory fails to account for the vast number of dog- and goat-sized dinosaur species which made up the bulk of the ecosystem during the ] Era.

	===Feathered dinosaurs and the origin of birds===
	{{main\|Feathered dinosaurs}}
	{{main\|Origin of birds}}

	Birds and non-avian dinosaurs share many features. Birds share over a hundred distinct anatomical features with ] dinosaurs, which are generally accepted to have been their closest ancient relatives.<ref>Mayr, G., Pohl, B. and Peters, D.S. (2005). A Well-Preserved Archaeopteryx Specimen with Theropod Features. ''Science'' 310:1483-1486..</ref>

	====Feathers====
	]''.]]

	'']'', the first good example of a "feathered dinosaur", was discovered in 1861. The initial specimen was found in the ] in southern Germany, which is a '']'', a rare and remarkable geological formation known for its superbly detailed fossils. Archaeopteryx is a ], with features clearly intermediate between those of modern reptiles and birds. Brought to light just two years after Darwin's seminal '']'', its discovery spurred the nascent debate between proponents of ] and ]. This early bird is so dinosaur-like that, without a clear impression of feathers in the surrounding rock, at least one specimen was mistaken for '']''.<ref name=PW88>Wellnhofer, P. (1988). Ein neuer Exemplar von ''Archaeopteryx''. ''Archaeopteryx'' 6:1–30.</ref>

	Since the 1990s, a number of additional ] have been found, providing even stronger evidence of the close relationship between dinosaurs and modern birds. Most of these specimens were unearthed in ] province, northeastern ], which was part of an island continent during the Cretaceous period. Though feathers have been found only in the ] of the ] and a few other places, it is possible that non-avian dinosaurs elsewhere in the world were also feathered. The lack of widespread fossil evidence for feathered non-avian dinosaurs may be due to the fact that delicate features like skin and feathers are not often preserved by ]ization and thus are absent from the fossil record.

	A recent development in the debate centers around the discovery of impressions of "protofeathers" surrounding many dinosaur fossils. Said protofeathers suggest that the ] may have been feathered.<ref>Xu, ''et al.'' "Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids." ''Nature.'' 2004 October 7; 431(7009):680-4. PMID: 15470426</ref> However, others claim that these protofeathers are simply the result of the decomposition of collagenous fiber that underlaid the dinosaurs' integument.<ref>Feduccia, ''et al.'' "Do feathered dinosaurs exist? Testing the hypothesis on neontological and paleontological evidence." ''J Morphol.'' 2005 Nov; 266(2):125-66. PMID: 16217748</ref>

	The feathered dinosaurs discovered so far include '']'', '']'', '']'', '']'', '']'', '']'', '']'', '']'', and '']''. Dinosaur-like birds like '']'', which are anatomically closer to modern avians, have also been discovered. All of these specimens come from the same formation in northern China. The ] family in particular seems to have been heavily feathered, and at least one dromaeosaurid, '']'', may have been capable of flight.

	====Skeleton====
	Because feathers are often associated with birds, feathered dinosaurs are often touted as the ] between birds and dinosaurs. However, the multiple skeletal features also shared by the two groups represent the more important link for ]s. Furthermore, it is increasingly clear that the relationship between birds and dinosaurs, and the evolution of flight, are more complex topics than previously realized. For example, while it was once believed that birds evolved from dinosaurs in one linear progression, some scientists, most notably ], conclude that dinosaurs such as the ]s may have evolved from birds, losing the power of flight while keeping their feathers in a manner similar to the modern ostrich and other ]s.

	]s, a diverse group of carnivorous dinosaurs that included '']'', are generally accepted to have been birds' closest relatives.]]
	Comparison of bird and dinosaur skeletons, as well as ], strengthens the case for the link, particularly for a branch of theropods called ]s. Skeletal similarities include the neck, ], ] (semi-lunate ]), arm and ], ], ] and ].

	====Reproductive biology====
	A discovery of features in a '']'' ] recently provided even more evidence that dinosaurs and birds evolved from a common ancestor and, for the first time, allowed paleontologists to establish the sex of a dinosaur. When laying eggs, female birds grow a special type of bone in their limbs. This ] bone, which is rich in calcium, forms a layer inside the hard outer bone that is used to make eggshells. The presence of endosteally-derived bone tissues lining the interior marrow cavities of portions of the ''Tyrannosaurus rex'' specimen's hind limb suggested that ''T. rex'' used similar reproductive strategies, and revealed the specimen to be female.

	A dinosaur embryo was found without teeth, suggesting that some parental care was required to feed the young dinosaur. It is also possible that the adult dinosaurs regurgitated into a young dinosaur's mouth to provide sustenance, a behavior that is also characteristic of numerous modern bird species.

	====Lungs====
	Large meat-eating dinosaurs had a complex system of air sacs similar to those found in modern birds, according to an investigation which was led by ] of ]. The lungs of theropod dinosaurs (carnivores that walked on two legs and had birdlike feet) likely pumped air into hollow sacs in their ]s, as is the case in birds. "What was once formally considered unique to birds was present in some form in the ancestors of birds", O'Connor said. The study was funded in part by the ].<ref>O'Connor, P.M. and Claessens, L.P.A.M. (2005). "Basic avian pulmonary design and flow-through ventilation in non-avian theropod dinosaurs". ''Nature'' 436:253.</ref>

	]'', a four-winged dinosaur with long ]s.]]
	====Heart and sleeping posture====
	Modern ] (CT) scans of a dinosaur chest cavity (conducted in 2000) found the apparent remnants of complex four-chambered hearts, much like those found in today's mammals and birds.<ref>Fisher, P. E., Russell, D. A., Stoskopf, M. K., Barrick, R. E., Hammer, M. & Kuzmitz, A. A. (2000). Cardiovascular evidence for an intermediate or higher metabolic rate in an ornithischian dinosaur. Science 288, 503–505.</ref> The idea is controversial within the scientific community, coming under-fire for bad anatomical science<ref>Hillenius, W. J. & Ruben, J. A. (2004). The evolution of endothermy in terrestrial vertebrates: Who? when? why? Physiological and Biochemical Zoology 77, 1019–1042.</ref> or simply wishful thinking.<ref>Dinosaur with a Heart of Stone. T. Rowe, E. F. McBride, P. C. Sereno, D. A. Russell, P. E. Fisher, R. E. Barrick, and M. K. Stoskopf (2001) Science 291, 783 </ref> A recently discovered ] fossil demonstrates that the dinosaurs slept like certain modern birds, with their heads tucked under their arms.<ref>Xu, X. and Norell, M.A. (2004). A new troodontid dinosaur from China with avian-like sleeping posture. ''Nature'' 431:838-841..</ref> This behavior, which may have helped to keep the head warm, is also characteristic of modern birds.

	====Gizzard====
	Another piece of evidence that birds and dinosaurs are closely related is the use of ] stones. These stones are swallowed by animals to aid digestion and break down food and hard fibres once they enter the stomach. When found in association with ]s, gizzard stones are called ]s. Because a particular stone could have been swallowed at one location before being carried to another during migration, paleontologists sometimes use the stones found in dinosaur stomachs to establish possible ] routes.

	===Evidence for Paleocene dinosaurs===
	In 2002, paleontologists Zielinski and Budahn reported the discovery of a single ] leg bone fossil in the San Juan Basin, New Mexico and described it as evidence of ]. The formation in which the bone was discovered has been dated to the early ] epoch approximately 64.5 million years ago. If the bone was not re-deposited into that ] by weathering action, it would provide evidence that some dinosaur populations may have survived at least a half million years into the Cenozoic Era.<ref>Fassett, J, R.A. Zielinski, & J.R. Budahn. (2002). Dinosaurs that did not die; evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico. In: Catastrophic events and mass extinctions; impacts and beyond. (Eds. Koeberl, C. & K. MacLeod): ''Special Paper - Geological Society of America'' 356: 307–336.</ref>

	===Soft tissue and DNA===
	One of the best examples of soft tissue impressions in a fossil dinosaur was discovered in ], ]. The discovery was reported in 1998, and described the specimen of a small, very young ], ''] samniticus''. The fossil includes portions of the intestines, colon, liver, muscles, and windpipe of this immature dinosaur.<ref name="softtissue" />

	In the March 2005 issue of '']'', ] and her team announced the discovery of flexible material resembling actual soft tissue inside a 68-million-year-old '']'' leg ] from the ] in ]. After recovery, the tissue was rehydrated by the science team.

	When the fossilized bone was treated over several weeks to remove mineral content from the fossilized bone marrow cavity (a process called demineralization), Schweitzer found evidence of intact structures such as ]s, bone matrix, and connective tissue (bone fibers). Scrutiny under the microscope further revealed that the putative dinosaur soft tissue had retained fine structures (microstructures) even at the cellular level. The exact nature and composition of this material, and the implications of Dr. Schweitzer's discovery, are not yet clear; study and interpretation of the material is ongoing.<ref>Schweitzer, M.H., Wittmeyer, J.L. and Horner, J.R. (2005). Soft-Tissue Vessels and Cellular Preservation in Tyrannosaurus rex. ''Science'' 307:1952–1955. Also covers the ]. </ref>

	The successful extraction of ancient DNA from dinosaur fossils has been reported on two separate occasions, but upon further inspection and ], neither of these reports could be confirmed.<ref>Wang, H., Yan, Z. and Jin, D. (1997). Reanalysis of published DNA sequence amplified from Cretaceous dinosaur egg fossil. ''Molecular Biology and Evolution''. 14:589–591. .</ref> However, a functional visual ] of a theoretical dinosaur has been inferred using analytical phylogenetic reconstruction methods on gene sequences of related modern species such as reptiles and birds.<ref>Chang, B.S.W., Jönsson, K., Kazmi, M.A., Donoghue, M.J. and Sakmar, T.P. (2002). Recreating a Functional Ancestral Archosaur Visual Pigment. ''Molecular Biology and Evolution'' 19:1483–1489. .</ref> In addition, several ]s have putatively been detected in dinosaur fossils,<ref>Embery, ''et al.'' "Identification of proteinaceous material in the bone of the dinosaur Iguanodon." ''Connect Tissue Res.'' 2003; 44 Suppl 1:41-6. PMID: 12952172</ref> including hemoglobin.<ref>Schweitzer, ''et al.'' "Heme compounds in dinosaur trabecular bone." ''Proc Natl Acad Sci U S A.'' 1997 Jun 10; 94(12):6291–6. PMID: 9177210</ref>

	Even if dinosaur DNA could be reconstructed, it would be exceedingly difficult to clone and "grow" dinosaurs using current technology since no closely related species exist to provide ]s or a suitable environment for ].

	==Extinction theories==
	{{main\|Cretaceous–Tertiary extinction event}}

	The sudden ] of non-avian dinosaurs, an event that occurred approximately 65 million years ago, is one of the most intriguing mysteries in ]. Many other groups of animals also became extinct at this time, including ]s (]-like ]s), ]s, plesiosaurs, pterosaurs, herbivorous ]s and ]s, most birds, and many groups of mammals.<ref name="changes">(November 2000). ''Earthwatch'' :6–13.</ref> The nature of the event that caused this mass extinction has been extensively studied since the 1970s; at present, several related theories are supported by paleontologists. Though the general consensus is that an impact event was the primary cause of dinosaur extinction, some scientists cite other possible causes, or support the idea that a confluence of several factors was responsible for the sudden disappearance of dinosaurs from the fossil record.

	===Asteroid collision===
	] at the tip of the ], the impact of which may have caused the dinosaur extinction.]]
	The asteroid collision theory, which was first proposed by ] in the late 1970s, links the ] at the end of the Cretaceous period to a ] impact approximately 65.5 million years ago. Alvarez proposed that a sudden increase in ] levels, recorded around the world in the period's rock stratum, was direct evidence of the impact. The bulk of the evidence now suggests that a 5–15 km wide ] hit in the vicinity of the ], creating the 170 km-wide ] and triggering the ]. Scientists are not certain whether dinosaurs were thriving or declining before the impact event. Some scientists propose that the meteorite caused a long and unnatural drop in Earth's atmospheric temperature, while others claim that it would have instead created an unusual heat wave.

	Although the speed of extinction cannot be deduced from the fossil record alone, various models suggest that the extinction was extremely rapid. The consensus among scientists who support this theory is that the impact caused extinctions both directly (by heat from the meteorite impact) and also indirectly (via a worldwide cooling brought about when matter ejected from the impact crater reflected thermal radiation from the sun).

	In September of 2007, ] researchers led by William Bottke of the ] in ], ], and ] scientists used ] simulations to identify the probable source of the Chicxulub impact. They calculated a 90% probability that a giant asteroid named ] (about 160 kilometres (100 miles) in diameter) orbiting in the asteroid belt which lies between ] and ], was struck by a smaller unnamed asteroid about 55 kilometres (35 miles) in diameter about 160 million years ago. The impact shattered Baptistina, creating a cluster which still exists today as the ]. Calculations indicate that some of the fragments were sent hurtling into earth-crossing orbits, one of which was the 10-km-wide (6-mile-wide) ] which struck ]'s ] ] 65 million years ago, creating the ] (175 kilometres wide (110 miles)). The researchers also calculated a 70% probability that an earlier-arriving fragment (108 million years BP) struck the ], creating the ]. Philippe Claeys of ] in ] stated that the findings were "''clear evidence that the solar system is a violent environment and that collisions taking place in the asteroid belt can have major repercussions for the evolution of life on Earth''."<ref></ref>

	===Multiple collisions—the Oort cloud===
	While similar to Alvarez's impact theory (which involved a single asteroid or comet), this theory proposes that "passages of the ] through the ] would trigger comet showers."<ref name="Koeberl">Koeberl, C. and MacLeod, K.G. (2002). ''Catastrophic Events and Mass Extinctions''. Geological Society of America. ISBN 0-8137-2356-6.</ref> One or more of these objects then collided with the Earth at approximately the same time, causing the worldwide extinction. As with the impact of a single asteroid, the end result of this comet bombardment would have been a sudden drop in global temperatures, followed by a protracted cool period.<ref name="Koeberl"/>

	===Environment changes===
	Before the mass extinction of the dinosaurs, the release of ]ses during the formation of the ] "contributed to an apparently massive ]. Some data point to an average rise in temperature of eight degrees Celsius (a change of 14.4 degrees Fahrenheit) in the last half million years before the ]]."<ref name="WRKtD">{{cite web\| author= Production Manager: Yolanda Ayres\|title=What Really Killed the Dinosaurs \|publisher=BBC Horizon\|url=http://www.bbc.co.uk/sn/tvradio/programmes/horizon/dino_trans.shtml}}</ref>

	At the peak of the dinosaur era, there were no ]s, and sea levels are estimated to have been from 100 to 250 meters (330 to 820 feet) higher than they are today. The planet's temperature was also much more uniform, with only 25 degrees Celsius separating average polar temperatures from those at the equator. On average, atmospheric temperatures were also much warmer; the poles, for example, were 50 °C warmer than today.<ref>: The effect climate change may have had on the extinction of the Dinosaurs</ref><ref> Sea levels during the dinosaur era; ]; ], ]</ref>

	The atmosphere's composition during the dinosaur era was vastly different as well. Carbon dioxide levels were up to 12 times higher than today's levels, and oxygen formed 32 to 35% of the atmosphere, as compared to 21% today. However, by the late ], the environment was changing dramatically. Volcanic activity was decreasing, which led to a cooling trend as levels of atmospheric carbon dioxide dropped. Oxygen levels in the atmosphere also started to fluctuate and would ultimately fall considerably. Some scientists hypothesize that climate change, combined with lower oxygen levels, might have led directly to the demise of many species. If the dinosaurs had respiratory systems similar to those commonly found in modern birds, it may have been particularly difficult for them to cope with reduced respiratory efficiency, given the enormous oxygen demands of their very large bodies.<ref name="changes" />

	==History of discovery==
	Dinosaur fossils have been known for millennia, although their true nature was not recognized. The Chinese, whose own word for dinosaur is ''konglong'' (恐龍, or "terrible dragon"), considered them to be ] ]s and documented them as such. For example, ''Hua Yang Guo Zhi'', a book written by Zhang Qu during the ], reported the discovery of dragon bones at Wucheng in ] Province.<ref>{{cite book\|author=]\|year=1992\|title=Dinosaurian Faunas of China\|publisher=China Ocean Press, Beijing\|id=ISBN 3-540-52084-8}}</ref> Villagers in central China have been digging up dinosaur bones for decades, thinking they were from dragons, to make traditional medicine.<ref>{{cite web\| last =\| first =\| authorlink =\| coauthors =\| title =Dinosaur bones 'used as medicine' \| work =\| publisher =BBC News\| date =2007\| url =http://news.bbc.co.uk/2/hi/asia-pacific/6276948.stm\| format =\| doi =\| accessdate =2007-07-06}}</ref> In Europe, dinosaur fossils were generally believed to be the remains of ] and other creatures killed by the ].

	].]]
	'']'' was the first dinosaur to be formally described, in 1677, when part of a bone was recovered from a ] ] at ] near ], ]. This bone fragment was identified correctly as the lower extremity of the ] of an animal larger than anything living in modern times. The second dinosaur genus to be identified, '']'', was discovered in 1822 by the English geologist ], who recognized similarities between his fossils and the bones of modern ]s. Two years later, the Rev ], a professor of ] at ], unearthed more fossilized bones of ''Megalosaurus'' and became the first person to describe dinosaurs in a ].

	The study of these "great fossil lizards" soon became of great interest to European and American scientists, and in 1842 the English paleontologist ] coined the term "dinosaur". He recognized that the remains that had been found so far, ''Iguanodon'', ''Megalosaurus'' and '']'', shared a number of distinctive features, and so decided to present them as a distinct taxonomic group. With the backing of ], the husband of ], Owen established the ] in ], ], to display the national collection of dinosaur fossils and other biological and geological exhibits.

	In 1858, the first known American dinosaur was discovered, in ] pits in the small town of ] (although fossils had been found before, their nature had not been correctly discerned). The creature was named ''] foulkii''. It was an extremely important find; ''Hadrosaurus'' was the first nearly complete dinosaur skeleton found and it was clearly a ] creature. This was a revolutionary discovery as, until that point, most scientists had believed dinosaurs walked on four feet, like other lizards. Foulke's discoveries sparked a wave of dinosaur mania in the ].

	], 19th century photograph.]]
	], 19th century photograph.]]

	Dinosaur mania was exemplified by the fierce rivalry between ] and ], both of whom raced to be the first to find new dinosaurs in what came to be known as the ]. The feud probably originated when Marsh publicly pointed out that Cope's reconstruction of an '']'' skeleton was flawed; Cope had inadvertently placed the ]'s head at what should have been the animal's tail end. The fight between the two scientists lasted for over 30 years, ending in 1897 when Cope died after spending his entire fortune on the dinosaur hunt. Marsh 'won' the contest primarily because he was better funded through a relationship with the ]. Unfortunately, many valuable dinosaur specimens were damaged or destroyed due to the pair's rough methods; for example, their diggers often used ] to unearth bones (a method modern paleontologists would find appalling). Despite their unrefined methods, the contributions of Cope and Marsh to paleontology were vast; Marsh unearthed 86 new species of dinosaur and Cope discovered 56, for a total of 142 new species. Cope's collection is now at the ] in ], while Marsh's is on display at the ] at ].<ref>Williams, P. (1997). The Battle of the Bones. ''Dinosaur Cards''. Orbis Publishing Ltd. D36040607.</ref>

	Since 1897, the search for dinosaur fossils has extended to every continent, including ]. The first Antarctic dinosaur to be discovered, the ]id '']'', was found on ] in 1986, although it was 1994 before an Antarctic species, the theropod '']'', was formally named and described in a scientific journal.

	Current dinosaur "hot spots" include southern South America (especially ]) and ]. China in particular has produced many exceptional ] specimens due to the unique geology of its dinosaur beds, as well as an ancient arid climate particularly conducive to ]ization.

	==Dinosaurs in culture==
	{{main\|Cultural depictions of dinosaurs}}
	]'' stalks ] in ].]]
	By human standards, dinosaurs were creatures of fantastic appearance and often enormous size. As such, they have captured the public imagination and become an enduring part of human culture. Only three decades after the first scientific descriptions of dinosaur remains, the famous ] were erected in ] in ]. These sculptures excited the public so strongly that smaller replicas were sold, one of the first examples of ] ]. Since Crystal Palace, dinosaur exhibitions have opened at parks and ] around the world, both catering to, and reinforcing, the public interest.<ref name="torrens1993">Torrens, H.S. (1993). "The dinosaurs and dinomania over 150 years." ''Modern Geology'' 18(2): 257-286.</ref> Dinosaur popularity has long had a reciprocal effect on dinosaur science, as well. The competition between museums for public attention led directly to the ] waged between Marsh and Cope, each striving to return with more spectacular fossil remains than the other, and the resulting contribution to dinosaur science was enormous.<ref name="breithaupt1997">Breithaupt, Brent H. (1997) "First golden period in the USA." In: Currie, Philip J. & Padian, Kevin (Eds.). ''The Encyclopedia of Dinosaurs''. Berkeley: University of California Press. Pp. 347-350.</ref>
	]'', itself a result of massive public interest in dinosaurs, catapulted the animals to new heights of popularity.]]
	Dinosaurs hold an integral place in modern culture. The word "dinosaur" itself has entered the English ] as an expression describing anything that is impractically large, slow-moving, or obsolete, bound for extinction.<ref name="m-w">"" Merriam-Webster's Online Dictionary. Accessed ] ].</ref> The public preoccupation with dinosaurs led to their inevitable entrance into worldwide ]. Beginning with a passing mention of ''Megalosaurus'' in the first paragraph of ]' '']'' in 1852,<ref name="bleakhouse">"''London. Michaelmas term lately over, and the Lord Chancellor sitting in Lincoln's Inn Hall. Implacable November weather. As much mud in the streets, as if the waters had but newly retired from the face of the earth, and it would not be wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborne Hill.''" From page 1 of Dickens, Charles J.H. (1852). ''Bleak House''. London: Bradbury & Evans.</ref> dinosaurs have been featured in a broad array of ]al works. ]'s 1912 book '']'', the iconic 1933 ] '']'', the 1954 introduction of '']'' and its many subsequent sequels, the best-selling 1990 novel '']'' by ] and its 1993 ], briefly the ], are just a few prominent examples of the long tradition of dinosaurs in fiction. ] authors, including some prominent paleontologists, have also sought to take advantage of dinosaur popularity, especially among children, to educate readers about dinosaurs in particular and science in general. Dinosaurs are ubiquitous in ], with numerous ] seeking to utilize dinosaurs to sell their own products or to characterize their rivals as slow-moving or obsolete.<ref name=DFGlut1997>Glut, Donald F, and Brett-Surman, Michael K. (1997) "Dinosaurs and the media." In: Farlow, James O. & Brett-Surman, Michael K. (Eds.). ''The Complete Dinosaur'' Bloomington: Indiana University Press. Pp. 675-697</ref>

	==Religious views==
	{{main\|Creationist perspectives on dinosaurs}}
	Various religious groups have views about dinosaurs that differ from those held by scientists, usually due to conflicts with ] in their scriptures. However, the ] community does not accept these religiously-inspired interpretations of dinosaurs.<ref name="Kitcher">{{cite book\| last =Kitcher\| first =Philip\| authorlink =\| coauthors =\| title = Abusing Science: The Case Against Creationism\| publisher =MIT Press\| date =1983\| location =\| pages = 213\| url =http://mitpress.mit.edu/catalog/item/default.asp?ttype=2&tid=5383\| doi =\| id = 978-0-262-61037-7 }}</ref><ref name="Dawkins">{{cite book\| last =Dawkins\| first =Richard\| authorlink =\| coauthors =\| title = The Blind Watchmaker: Why the Evidence of Evolution Reveals a Universe Without Design\| publisher =W.W. Norton\| date =1996\| location =\| pages =400\| url =\| doi =\| id =978-0393315707}}</ref>

	==See also==
	{{portalpar\|Dinosaurs}}
	* ]
	* ]s
	* ]
	* ] ''(with link directory)''
	* ]
	* ]
	* ]s

	==Notes and references==
	{{reflist\|2}}
	<!-- Dead note "reptilia": From the classical standpoint, reptiles included all the amniotes except birds and mammals. Thus reptiles were defined as the set of animals that includes crocodiles, alligators, tuatara, lizards, snakes, amphisbaenians and turtles, grouped together as the class Reptilia. However, many taxonomists have begun to insist that taxa should be monophyletic, that is, groups should include all descendants of a particular form. The reptiles as defined here would be paraphyletic, since they exclude both birds and mammals, although these also developed from the original reptile. Thus, some cladists redefine Reptilia as a monophyletic group, including both the classic reptiles as well as the birds and perhaps the mammals (depending on ideas about their relationships). Others abandon it as a formal taxon altogether, dividing it into several different classes. -->
	<!-- Dead note "jpii": Catholic Opinions on Evolutionary Origins. -->

	==General references==
	<div class="references-small">
	* Kevin Padian, and Philip J. Currie. (1997). ''Encyclopedia of Dinosaurs''. Academic Press. ISBN 0-12-226810-5. (Articles are written by experts in the field).
	* ] (2000). ''The Scientific American Book of Dinosaurs''. St. Martin's Press. ISBN 0-312-26226-4.
	*Paul, Gregory S. (2002). ''Dinosaurs of the Air: The Evolution and Loss of flight in Dinosaurs and Birds''. Baltimore: The Johns Hopkins University Press. ISBN 0-8018-6763-0.
	*] (2004). ''The Dinosauria''. University of California Press; 2nd edition. ISBN 0-520-24209-2.
	</div>

	==External links==
	<!--Sorted (roughly) from least to most technical-->
	{{commons\|Dinosauria}}
	{{Spoken Misplaced Pages\|Dinosaur.ogg\|2005-12-30}}
	<!-- link to the recorded version: http://en.wikipedia.org/search/?title=Dinosaur&oldid=33253062 -- It should be inserted into the template, as an actual link, because it's rather laborious to roll back among thousands of changes and find a specific revision in the history.-->

	;For children
	* (''www.enchantedlearning.com'') From Enchanted Learning. Kid's site, info pages, theories, history.

	;Images
	* of The Dinosauricon, hosting over 2000 images from many different artists working in different styles.
	*, featuring skeletal restorations of a variety of prehistoric animals.
	* Professional restorations of numerous dinosaurs, and discussions of dinosaur anatomy.

	;Popular
	*: From the ], a well illustrated dinosaur directory.
	<!--* (''www.dinosaur.org'') The first online dinosaur magazine.(cited in ''The Dinosauria'')-->
	* (''www.dinosaurnews.org'') The dinosaur-related headlines from around the world. Recent news on dinosaurs, including finds and discoveries, lots of links.
	* From UC Berkeley Museum of Paleontology Detailed information - scroll down for menu.
	* All about dinosaurs, with current featured articles.
	* hosts a large collection of dinosaur-related links.

	;Technical
	* From Coquina Press. Online technical journal.
	* A searchable dinosaur database, from the University of Bristol, with dinosaur lists, classification, pictures, and more.
	* (''www.dinodata.org'') Technical site, essays, classification, anatomy.
	* (''www.dinosauria.com'') Technical site, essays, pronunciation, dictionary.
	* By T. Michael Keesey. Technical site, cladogram, illustrations and animations.
	* By Justin Tweet. Includes a cladogram and small essays on each relevant genera and species.
	* From . A detailed amateur site about all things paleo.
	*, an extensive overview of genera-based dinosaur information from 1999 and before.

	{{featured article}}

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	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]
	]

Revision as of 18:32, 10 October 2007