1809 - A lower
shin- bone of a large unknown animal was collected at Cuckfield by William
Smith ("Father of English Geology"). This fossil was deposited at the British
Museum in London and years later was identified as that of Iguanodon.
Dinosaur fossils had been known for centuries as "dragon bones" or the remains of giants, but it wasn't until Dean William Buckland of Oxford, England described the carnivorous "lizard" Megalosaurus (in 1824) that they were formally studied as an extinct group of giant reptiles. The English country doctor Gideon Mantell described Iguanodon in 1825, and today there are more than 800 known types of non-avian dinosaurs (plus some 10,000-plus birds).
The term "Dinosauria" was invented by Sir Richard Owen in 1842 to describe these "fearfully
great reptiles", specifically Megalosaurus, Iguanodon, and Hylaeosaurus,
the only three dinosaurs known at the time. The irony of Owen's invention of Dinosauria is
that he devised the taxonomic group as an argument against progressive evolution, but
actually had presented evidence supporting evolution.
The First Discoveries
The clade Dinosauria was originally defined by Sir Richard Owen in 1842, in a two hour speech that reportedly held the audience captivated. The original dinosaurs of this new group were Megalosaurus, Iguanodon and Hylaeosaurus. However, each of these animals was known only from fragmentary specimens. It wasn't until the discoveries of dinosaurs in North America in the mid-19th century that people began to get a clearer picture of what dinosaurs looked like.
It is generally accepted that the first discovery of dinosaur remains in North America was made in 1854 by Ferdinand Vandiveer Hayden during his exploration of the upper Missouri River.
Near the confluence of the Judith and Missouri Rivers (shown
above) Hayden's party recovered a small collection of isolated teeth which were later
described by the Philadelphia paleontologist Joseph Leidy in 1856, in the Proceedings
of the Academy of Natural Sciences of Philadelphia.
An important, more complete
specimen
A short two years later, Leidy had the honor of describing
the first reasonably complete dinosaur skeleton the world would know, Hadrosaurus foulkii. Named after its
discoverer William Parker Foulke, this specimen was
recovered during quarrying of a sand pit in Haddonfield, New Jersey.
The real significance of this specimen was in its limb
proportions. For the first time scientists studying these animals could see that some
dinosaurs were bipedal, walking on two legs instead of on all fours. Bipedalism was a
revolutionary thought for a reptilian posture.
This specimen, now on display at the Academy of Natural Sciences of Philadelphia, was
originally mounted in a free-standing bipedal pose by Benjamin Waterhouse Hawkins in 1868.
The records for attendance at the Academy show that visitation increased three-fold with this new exhibit, testimony to the public's long-standing and intense fascination with dinosaurs.
For many years, Hadrosaurus foulkii was the only dinosaur on public display.
Duplicate casts of the skeleton were made for other institutions both in the United States
and in Europe.
Events surrounding the discovery of the Bushmans River dinosaur.
- 1845 - Dr WG Atherstone and Mr AG Bain discovered the fossil of "Cape Iguanodon" in the Bushmans River valley near Dassieklip[1].
1849 & 1853 - Bain sent collections of SA fossils to the Natural History Museum in London for identification by Sir Richard Owen. This material included the lower jaw of the "Cape Iguanodon" from Bushmans River[5,6].
1857 - Dr WG Atherstone[1] published the account of their trip to the Bushmans River valley and the discovery of this fossil.
1871 - Dr WG Atherstone[7] mentioned that the "Cape Iguanodon" had still not been identified and that it was still housed in the Natural History Museum in London.
1876 - Sir Richard Owen published an illustrated description of the fossil of "Cape Iguanodon" and named it Anthodon serrarius[8] .
1890 - Richard Lydekker[6], a curator of palaeontology at the British Museum of Natural History in London, corrected Owen's mistake regarding the locality yet failed to distinguish them as separate species - Anthodon serrarius, a pareiasaur and "Cape Iguanodon" a dinosaur.
1909 - Dr Robert Broom visited the British Museum of Natural History and examined the Bushmans River material. He concluded that the fossil was in fact from a herbivorous dinosaur and noted that "..... when we compare the teeth with those of Cretaceous reptiles of other parts we find that they are strikingly similar to those of some herbivorous Dinosaurs"[9]. Broom noted a striking similarity between the Bushmans River teeth and a tooth of Palaeoscincus costatus, an ankylosaur which is now regarded as a close relative of the stegosaurs. He went on to suggest that as the Bushmans River teeth were so similar to those of the ankylosaur Palaeoscincus costatus it was probable that they belonged to the same genus. He recommended that the Bushmans River specimen be provisionally named Palaeoscincus africanus, emphasizing that it was definitely not the pareiasaur Anthodon serrarius and pretty certainly dinosaurian.
1913 - Prof. E.H.L. Schwarz and students from Rhodes University revisited the discovery site and they found more fossil bone, including a heavy femoral head, the head of a tibia, some vertebra and numerous smaller fragments[10]. These specimens (a total of 22 fragments) are housed in the Albany Museum. In describing this material Schwarz, however, did not adopt the name proposed by Broom and persisted with the mistaken name Anthodon serrarius. Recent examination of this material suggests that it may not be from a stegosaur but rather from some large sauropod dinosaur. This material was however collected in the general area where Atherstone found the stegosaur.
1929 - Frans Baron Nopsca[11], apparently unaware of the name proposed by Broom, studied the Bushmans River fossil at the British Museum of Natural History and named it Paranthodon oweni recognizing that it was in fact a stegosaur. He introduced the new stegosaur genus Paranthodon into the literature.
1972 - Walter P. Coombs examined the fossil and requested that it be prepared for detailed study[2].
1981 - Peter M. Galton and Walter P. Coombs tied up most of the loose ends of this saga and establish the taxonomy of this specimen in their paper entitled "Paranthodon africanus (Broom) - A Stegosaurian Dinosaur from the lower Cretaceous of South Africa"[2] .
Remains of Dinosaurs
If the diverse and numerous dinosaurs (except birds) are extinct, then how
can we better understand they lived? Despite the fact that the great dinosaurs of the Mesozoic are gone, they have left us many clues about
what they looked like and how they lived. This is because dinosaur fossils are not limited
to bones, but include skin, eggs, nests, footprints, and other special kinds of fossils
that give us clues about their lifestyles.
Dinosaur Nests
The news has recently carried several stories of wonderful finds of nesting dinosaurs, and it is true that an explosion of data on dinosaurian nesting and social behavior has been uncovered in the past 20 years. Some of the most well known and compelling evidence comes from Dr. Jack Horner's (Museum of the Rockies) ongoing work at the "Egg Mountain" site in Montana, where he has documented evidence of a large nesting area used by hadrosaurian (duckbill) dinosaurs. These dinosaurs were named Maiasaura, "good mother reptile," referring to the closely packed nests that contain fossilized eggs, embryos, and juveniles (such as the one pictured at right). This is one case where we can be fairly confident that parental care was involved in these dinosaurs' lifestyle. Actually, this is not a surprising assertion, because both crocodilians (their closest living relatives) and birds (their living descendants), both show some degree of parental care and extensive nest building.
Other dramatic finds of dinosaur nests include theropod dinosaurs (Oviraptor and Troodon) that apparently died while brooding their nests, and abundant nests of the early ceratopsian dinosaur Protoceratops. An interesting story about Oviraptor: the so-called "egg stealer" was so named because it was found atop a clutch of eggs that were assumed to belong to Protoceratops. This idea held for some 70 years until a find in the 1990s showed an Oviraptor embryo inside one of those eggs... Egg stealer exonerated!
We know of literally thousands of non-avian dinosaur footprints scattered around the globe, from Late Triassic to Late Cretaceous age. You might not think that a footprint, or a sequence of footprints (called a trackway), could tell us much, but actually it can tell us some general things about the biology of dinosaurs.
From trackway data, we can tell that (1) some non-avian dinosaurs travelled in large groups; (2) non-avian dinosaurs moved with their feet held underneath their body (as birds and mammals do); and (3) some non-avian dinosaurs moved rather quickly, but some plodded along at a more leisurely pace -- see our section on dinosaur speeds for more info. See Dinosaurs Tracks
Dinosaur Diet
Dinosaurs, living and extinct, have varied diets. We have some strong evidence of exactly what the diets of some of the extinct dinosaurs was, and we can observe birds directly to learn about their diets. Dentition (tooth structure) is one of the most abundant lines of evidence useful for determining dinosaur diets. Most ornithischian and sauropodomorph dinosaurs had rather simple, short stubby crenellated teeth, which are similar to those of living herbivores, and clearly not too good for eating much meat.
Theropod teeth, on the other hand, retain the primitive archosaurian characteristic of being recurved, serrated, laterally -compressed, and knife-like. There is some variation in tooth structure among extinct theropods, but most are fairly similar and obviously related to a carnivorous diet.
Stomach contents are another line of evidence, somewhat more direct but also a bit more tricky to interpret accurately. Well-preserved dinosaur skeletons sometimes have traces of apparent food items preserved in their abdominal cavity, where it's safe to assume that they had a stomach. This includes pine cones and/or needles in some herbivores' guts, and traces of some vertebrates in some theropods' guts. So this independent line of inquiry substantiates the data from tooth morphology. Also, some sauropodomorph stomachs contain well- rounded stones, caled gastroliths, that were probably used to grind food in a muscular crop or gizzard, like some birds (and crocodilians) do.
The general hypothesis that most ornithischians and sauropodomorphs were largely, if not completely herbivorous, and that theropods (at least before the origin of birds) were mostly carnivorous, thus holds. More specific hypotheses have been proposed and supported by data, while others have fallen by the wayside. It is likely that new discoveries will illuminate more about dinosaur diets as the global "dinosaur renaissance" continues.
You can learn more about the diets of sauropods from our page on that
subject.
Dinosaur Classes
With the discovery of many new species since the 1840s, the Dinosauria now contains two major groups of dinosaurs: the Ornithischia, or "bird-hipped" dinosaurs, and the Saurischia, or "lizard-hipped" dinosaurs. The division between the two groups was made by H.G. Seeley in 1888. The etymology behind the two names ("bird-hipped" vs. "lizard-hipped") is not very accurate, since some saurischians had bird-like hips, and ornithischians' hips were somewhat birdlike due to convergent evolution, not due to direct ancestry. In fact, birds are saurischians! Goto Dinosaur Groups to see examples.
Saurischia contains two main groups:
- Sauropodomorpha is the first group, and includes both the "prosauropods" -- a probably paraphyletic (artificial) group of largely herbivorous, dominantly quadrupedal dinosaurs such as Plateosaurus; and the Sauropoda: long-necked, long-tailed, enormous herbivorous dinosaurs like Apatosaurus (formerly called Brontosaurus), Brachiosaurus, and Diplodocus.
- Theropoda is the second saurischian group, consisting of the carnivorous dinosaurs. The Theropoda includes some extinct dinosaurs such as Tyrannosaurus rex and Dilophosaurus, but it also includes the living dinosaurs -- the birds.
Ornithischia contains several groups of herbivorous dinosaurs, including several basal groups, but primarily three large ones:
- Thyreophora includes the various armored dinosaurs, like Stegosaurus and Ankylosaurus.
- Marginocephalia consists mainly of the pachycephalosaurs (bone-heads) and the ceratopsians (horned dinosaurs), like Triceratops.
- Ornithopoda is the third Ornithischian group, and includes not only small bipedal plant-eaters like Heterodontosaurus, but also the often large hadrosaurs, or "duck-billed dinosaurs", like Maiasaura and Edmontosaurus.
Dinosaurs and other Mesozoic Animals
| Acrocanthosaurus | |||
Coelophysis |
|||
Compsognathus |
Maiasaura |
||
|
|||
Dilophosaurus |
Ornithomimus |
||
| Archaeopteryx | Oviraptor |
||
| Bagaceratops | |||
Plateosaurus |
|||
Edmontosaurus |
Procompsognathus |
||
| Brachyceratops | Prosaurolophus | ||
| Camarasaurus | Protoceratops Protoceratops |
||
| Camptosaurus | Eoraptor |
Psittacosaurus | |
| Pterosaur Pterosaur |
|||
Centrosaurus |
Saltopus |
||
Ceratosaurus |
Hadrosaurus |
Saurolophus |
|
| Heterodontosaurus | |||
DinoData Dinosaur Index
Exhibits A-Z
Dinosaur Types
Jurassic Dinosaurs
Cretaceous Dinosaurs
Extinction
Go to
Blast From the Past To see the Asteroid Theory of Extinction
Sixty-five million years ago the curtain came down on the Age of Dinosaurs when a
cataclysmic event led to mass extinctions of life. This interval of abrupt change in
Earth's history, called the "K/T Boundary", closed the Cretaceous (K) Period and
opened the Tertiary (T) Period.
A recently recovered deep-sea core provides convincing
support to the hypothesis that an asteroid collision devastated terrestrial and marine
environments world-wide. It shows a record of flourishing marine life before the event,
followed by mass extinction and then evolution of new species and slow recovery of
surviving life forms after the event.
There have been LOTS of extinctions that affected animals
besides dinosaurs. There were even some that the dinosaurs lived through and survived.
- Cretaceous-Tertiary extinction, about 65 million years
ago - loss of land animals including dinosaurs. probably caused or aggravated by
impact of several-mile-wide asteroid that created the Chicxulub crater now hidden on the
Yucatan Peninsula and beneath the Gulf of Mexico. Some argue for other causes, including
gradual climate change or flood-like volcanic eruptions of basalt lava from India’s
Deccan Traps. The extinction killed 16 percent of marine families, 47 percent of marine
genera (the classification above species) and 18 percent of land vertebrate families,
including the dinosaurs.
- End Triassic extinction, roughly 199 million to 214
million years ago - loss of marine animals. most likely caused by massive floods of
lava erupting from the central Atlantic magmatic province -- an event that triggered the
opening of the Atlantic Ocean. The volcanism may have led to deadly global warming. Rocks
from the eruptions now are found in the eastern United States, eastern Brazil, North
Africa and Spain. The death toll: 22 percent of marine families, 52 percent of marine
genera. Vertebrate deaths are unclear.
- Permian-Triassic extinction, about 251 million years
ago - loss of land species: animals, plants, insects. Many scientists suspect a
comet or asteroid impact, (scientist estimates the object was 9 to 12 miles (15 to 20
kilometers) wide.) although direct evidence has not been found. Others believe the
cause was flood volcanism from the Siberian Traps and related loss of oxygen in the seas.
Still others believe the impact triggered the volcanism and also may have done so during
the Cretaceous-Tertiary extinction. The Permian-Triassic catastrophe was Earth’s
worst mass extinction, killing 95 percent of all species, 53 percent of marine families,
84 percent of marine genera and an estimated 70 percent of land species such as plants,
insects and vertebrate animals. Recent analysis of South African rocks reveals that
rivers suddenly became clogged with sediments 251 million years ago, indicating Earth’s
worst mass extinction wiped out many trees and other plants that held soil in
place. Sedimentary rocks from that time show that large meandering rivers throughout
South Africa’s Karoo Basin took on a braided, multichannel appearance, resembling
streams in areas devastated by Mount St. Helens’ big eruption or areas logged by
clear-cutting. That supports the notion of a global die-off of land plants, including
extinction of Glossopteris trees and bushes, which resembled modern ginkos. Ward
said a variety of ferns, seed ferns and early pine trees also went extinct. In July,
Doug Erwin of the Smithsonian Institution’s National Museum of Natural History
published a study in Science in which marine rocks from China revealed the
Permian-Triassic extinction happened in less than 160,000 years. And in July’s
issue of the journal Geology, a study of seafloor rocks now in the Austrian Alps
concluded the extinction happened in less than 60,000 years and perhaps in less than 8,000
years.
- Late Devonian extinction, about 364 million years ago
- loss of marine animals cause unknown. It killed 22 percent of marine families and 57
percent of marine genera. Erwin said little is known about land organisms at the
time.
- Ordovician-Silurian extinction, about 439 million years ago - loss of marine animals caused by a drop in sea levels as glaciers formed, then by rising sea levels as glaciers melted. The toll: 25 percent of marine families and 60 percent of marine genera
Webs Sites
Dinosauria
On-Line Dinosaur Omnipedia
Dinosaurium Hooper
Virtual Natural History Museum. The Department of Earth Sciences, Carleton
University, Ottawa, Ontario, Canada
Dinosaur List This
page lists all known Dinosaur genera.
Dinosaur News Here
you will find all the latest bits of dinosaur news. New discoveries, theories, statements,
research, etc. Be the first to find out.
Dinosauria Translation and Pronunciation
Guide A Pronunciation, meaning, and information of all dinosaur species.
Dinosaurs
End, The Gravitational Process
Earth's Geologic Time Line
Journal of Dinosaur Paleontology
Oceans of Kansas Paleontology: Fossils From the
Western Interior Sea
Official State Dinosaur Page