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Superorder Dinosauria

Intro | Dino Types | Links | Books

Painting © Doug Henderson, reproduced with permission.

Probably no creatures that have lived upon this Earth have excited the imagination more than the Dinosauria.  For some 150 million years they dominated ever medium to large to gigantic terrestrial vertebrate ecological niche, evolving into a wide range of forms and populating every continent.

Perhaps because they often had such bizarre forms, perhaps because they sometimes grew to such huge size, perhaps because after ruling this earth for so long they suddenly vanished, seemingly without a trace; all things add to the appeal of the dinosauria in the popular imagination.

In fact it turns out, as with so many other things, that the popular imagination is mistaken.  True, many dinosaurs did have rather strange forms, but were they any stranger in appearance than, say, a giraffe or an elephant?   True, many of them did grow to be quite large and even enormous size, but no dinosaur has ever rivalled even the smaller baleen whales in size.   It would in fact be physiologically impossible for a land animal of more than 100 tonnes to exist (it's legs would have to be so massive they would touch, leaving no space for the body between!).  So much for Godzilla and the dinosaurs of One Million Years B.C. (a laughable film better known for Rachel Welch in her animal-skin bikini) - such creatures belong to the realm of Hollywood fantasy.   The majority of dinosaurs were actually medium-sized creatures, equivalent to modern medium to large mammals in size.  Finally, as for dying out without a trace, this is also incorrect.  One lineage of small insectivorous/carnivorous dinosaurs did survive the great Mesozoic terminal extinction and are still with us today.  They're called birds.

Some ecological niches the dinosaurs didn't invade.  They never established themselves in the small terrestrial vertebrate niche (this was already taken over by mammals and lizards), nor (contrary to popular belief) did any of them ever adopt a marine or aquatic mode of life.  They did however take over the air with style; and so successfully that their descendents are still the most numerous and diverse of the link to palaeos com tetrapod (land-living vertebrates) even today.

UCMP The Dinosauria: Truth is Stranger than Fiction - an excellent introduction to the group

Dinosaur Groups

Conventionally, the dinosaurs are divided into two orders, depending on the structure of the hip bones.  Those that had a reptilian-like pelvic bone were put in the Order Saurischia or "lizard-hips"; while the ones with a bird-like pelvic bone made up the Order Ornithischia or "bird-hips".  (Paradoxically, it was the "lizard-hipped" and not the "bird-hipped" forms that evolved into birds).  This classification is still adhered to in most (especially older) popular and academic books, but has pretty much been rejected in favour of the cladistic interpretation.  My own position is that both the conventional Linnean and the Cladistic arrangements have good and bad points, and in a sense each supplements the other.

Dinosaurs - the Linnean Classification
Dinosaurs - the Cladistic Classification

Putting together a website allows one certain indulges, one of which is to present one's own interpretation of life, the universe, and everything (which may indeed be no better and no worse than anyone else's interpretation). The following, then, is my take on Dinosaur systematics and classification. Beginning with the Linnean approach (which is now out of fashion in most biology and paleontology books and web sites, but which still has certain advantages) I would divide the Superorder (this being the most appropriate Linnean ranking) Dinosauria into four orders as given below.

LagosuchusThe earliest proto-dinosaurs (or ancestral "Ornithodira") are a group of small early dinosaur-like archosaurs that do not fit into either the Saurischia or Ornithischia category.  These creatures, previously considered Ornithosuchian thecodonts, are not even formally considered dinosaurs (although they could be called "dinosauromorphs", which means dinosaurs and a few related ancestral forms). But they are the stem forms from which the others all evolved.  It has also for some years been suggested that they are ancestral to the Pterodactyls (flying reptiles), in which case one could follow Dr Bob Bakker in including the Pterosaurs under the Dinosauria (as a fifth linnean order). There is however a rival and equally persuasive theory which derives the pterosaurs from Prolacertiform "lizards" (archosauromorphs). This latter theory is favoured by David Peters in the (no longre on-line) Pterosaur Home Page.

TyrannosaurusThe Saurischia or "lizard hipped" dinosaurs are conventionally divided in turn into two groups, one carnivorous,  the other herbivorous.  The first of these are the Theropoda, the bipedal carnivorous dinosaurs, with their bird-like legs and necks.  Theropoda means "beast-feet", a rather inappropriate name; "bird(-like) feet" would have been better.  Included in this huge and diverse group are both small forms (among them the ancestors of birds) and large predators such as Allosaurus and Tyrannosaurus.  The Theropoda are such a diverse group of animals they should really be considered an order rather than a suborder (in the Linnean hierarchy)

RebbechisaurusThe other group of Saurischia, the Sauropodamorpha, are the herbivores.  There are two main subgroups, the Sauropoda (the inappropriately named "lizard-feet"), and their ancestors, the Prosauropoda ("before the sauropods".  Although the primitive Prosauropods were relatively small, the more advanced types, and especially all of the Sauropods, were elephantine giants with tiny heads, very long necks and tails, massive bodies, and pillar-like legs.  This group includes the famous Brontosaurus (or Apatasaurus) and its relatives.  Like modern-day elephants, they relied on their great size as a defense against carnivores.

TriceratopsThe Ornithischia ("bird hipped" dinosaurs), or Predentata (so called beacuse they posses a unique extra bone in front of the jaw, which served as a sort of beak) were a more diverse group of herbivores.  Being much smaller than the sauropods, they had to evolve various other means to protect themselves against their meat-eating theropod contemporaries.  The inoffensive Ornithopods depended on fleetness of foot and acute sight and hearing.  The Ceratopsian dinosaurs (Triceratops, etc) were the rhinoceroses of the dinosaur world, their formidable horns ample protection against even the largest and fiercest carnivores.  And the Stegosaurs and Ankylosaurs evolved armour plates, spikes, and tail-clubs as defensive and offensive weapons.

The Ornithischia - unlike Saurischian dinosaurs, reptiles and birds - possessed mammalian cheek- muscles and -pouches to aid in the chewing.  In this respect they paralleled the mammalian form.  Certainly, many ornithischia filled similar ecological roles to mammalian ungulates.

So we see among the dinosaurs the tendency towards both an avimorphisation or bird-form-tendency in the Theropods, and a theromorphisation or mammal-form-tendency) in the Ornithischia.  The dinosaurs of the link to palaeos com Mesozoic era in a sense presaged the birds and mammals of the link to palaeos com Cenozoic era.

(Lizard Hipped dinosaurs)
Ornithischia (Bird Hipped dinosaurs)

A word now about birds.

Many palaeontologists and dino-enthusiasts nowadays also consider the Birds to be a subgroup of dinosaurs.  Cladistically (phylogenetically) speaking this is correct: birds evolved from dinosaurs, so if dinosaurs are to retain their monophyletic status (which is necessarily if they are to remain a valid taxon in the eyes of the cladists) they have to include Birds.

There is no denying birds are indeed very dinosaur-like in many ways.  My own feeling is that Birds have the same relationship to Dinosaurs as link to palaeos com mammals have to Therapsids (mammal-like reptiles).  One option might be to consider the Birds as a superorder of link to palaeos com Archosaurs alongside the paraphyletic Superorder Dinosauria. Birds thus constitute the culmination of link to palaeos com Sauropsid evolution, just as mammals constitute the culmination of link to palaeos com Theropsid evolution.

Aves (Protobirds and True Birds)

books DVDsBooks, DVDs and Web Links Web links

Dinosaurs seem to be the most popular form of prehistoric creature on the Web.  Here are some of the better dino sites, grouped according to topic.

Note - this list of links is in no way intended to be definitive, or even one quater complete!  But by following links from some of these links you can find more dino sites.

general sites
specific species
dinosaur art
dinosaur icons
technical papers
other paradigms true and (more often) false

Dinosauria Sites - general

There are so many dinosaur sites on the web it's ridiculous.  Most of them are generally orientated to kids, but there are still a few good ones.

UCMP page The Dinosauria: Truth is Stranger than Fiction
a good overall intro, but not as much detail as some other sites

The Dinosauricon The Dinosauricon (formerly the Dinosaur Pages) by T.Mike Keesey.  The mother of all dinosaur sites!  Lists every known family, genus and species, gives evolutionary relationships between genera, and includes glossary, art gallery, charts, links, glossary, and "ask Mike" forum.  The Dinosauricon's server was down for some months but is now back on line.

web site Dinosaurs! Gone, But Not Forgotten - a good non-technical introduction, with original dinosaur art. Covers all the main groups of dinosaurs

web site The Dinosaur Web

Dinosauria On-line by Jeff Poling
Including Dinosaur Omnipedia, Picture Gallery
Articles and discussions from enthusiasts and actual paleontologists on various dinosaur topics

Dinosaur Database DINOBASE - the Dinosaur Database

Dinosaur Reference Center The Dinosaur Reference Center

web sitefeatures cladogram Thescelosaurus! Justin Tweet's Dinosaur site includes not only the obigatory cladogram and summary of each group, but also a short but very informative description of each species

Walking with dinosaursaudio (requires Real Player) The site of the excellent abc/bbc TV series that featured computer reconstructed dinosaurs.  Beats Jurassic Park any day!  The site has some real play clips from the series, also fact files and info about the making of each episode. Get the DVDs of the series!

web pagedrawingaudio (requires Real Player)sound Fossil Zone - includes Dinosaur sounds and movement - by the Discovery Channel On-line

web pagelinks Nearctica - Paleontology - Dinosaurs - Main Page - good annoitated list of links

web pagelinks Dinosaur Topics - a good list of links

Dinosaur mailing list archives Dinosaur Internet mailing list Archives

web page Mesozoic Meanderings - despite the name, just on dinosaurs only but quite a good site

coverage of specific species

Dinosaur Kingdom (Japanese & English) Nakasato Dinosaur Kingdom
Nakasato Virtual Museum

web pageart worklinks Dann's Dinosaur Reconstructions  includes descriptions of a number of less well-known dinosaurs, and also Australian Mesozoic marine reptiles.

Dinosaurs of Colorado includes general info on dinosaurs as well - quite a few links

Dinosaur Art

Dinosaur Illustrations Dinosaur Illustrations - large index of links to Prehistoric Art - mostly dinosaurs but a few other prehistoric creatures here as well.  The site to go to to look for quality dino art.

web pagephotosart workDINO RUSS's COLLECTION OF DINO GIF's a lot of material available on this site, mostly photos and drawings; includes some material by Greg Paul.

web siteart work Douglas Henderson's Earth History Gallery - Doug Henderson is without doubt one of the greatest paleo-life artists around

web siteart work Brian Franczak's Paleolife Art - really fantastic paintings!  Another superb paleo artist

web siteart work MICHAEL WILLIAM SKREPNICK - Dinosaur Art - only a few images here, but they are all excellent

web siteart work Candi's Dino Art - really neat dino images, mostly theropods

web sitegraphics Paleontological Illustration - Frank DeNota

web siteart workDawn of Time Art Gallery - Dinosaur Paintings and Sculptures
featuring original Dinosaur Art by Mark Hallett, Douglas Henderson, and others

web siteart work Dinosaur Art and Modeling - features work by different artists

several web pagesart work Black and White Dinosaur Clipart - it is not as good as some of the professional stuff listed above, but it is free! (public domain).

Dinosaur Icons

JurassIcon Park - collection of general-purpose dinosaur icons

web pageart work Dinosaur Icons - a nice selection of icons by various artists

Technical Papers

on-line textLower to Middle Cretaceous Dinosaur Faunas of the Central Colorado Plateau. This paper was originally published in Brigham Young University Geology Studies, Volume 42, Part Two [1997], pages 69-103.

other paradigms

(true and (more often) false)

web siteart work The Great Dinosaur Mystery - this is a Creationist site, and although polemical still raises some good points - e.g. the page on species and taxonomy - there is also heaps of misinformation as well.

books Books and DVDs CD Roms

In Association with


Simple Basic Intermediate Advanced very technical not rated
Simple non-technical Intermediate Advanced very technical not rated
want to describe or rate a book? Or think my rating sux? Contact me

CD Rom Walking With Dinosaurs - if you haven't seen this magnificent series you are doing yourself a disservice. Makes Jurassic Park look like amateurs. - 5 star rating

CD Rom Allosaurus - A Walking With Dinosaurs Special The life and times of Big Al 5 star rating

Books from least to most Technical:

non-technical The Simon and Schuster Encyclopedia of Dinosaurs and Prehistoric Creatures: A Visual Who's Who of Prehistoric Life by Douglas Palmer, Barry Cox (Editor), R. J. G. Savage, Brian Gardiner, Douglas Dixon - more 3 star rating

non-technical Dinosaurs by Eugene S. Gaffney, illustr. by John Dawson - a simple guide and intro to Dinosaurs. If you want more detail you need to go for one of the following books

non-technical The Horned Dinosaurs by Peter Dodson - everything you wanted to know about these amazing creatures - (not yet rated)

intermediate Dinosaurs: The Encyclopedia by Donald F. Glut - superb alphabetical listing of every known genus! Requires a little technical knowledge but that is unavoidable with a subject like this. In fact, this is an extremely readable, wonderfully comprehensive book. Make sure you get the supplements - so far one and two are available - as well. 5 out of 5 stars

book in print Ultimate Dinosaur Book by David Lambert, John H. Ostrom (not yet rated)

Book in Print In the Presence of Dinosaurs by John Colagrande, Larry Felder (Illustrator), Jack Horner - (not yet rated)

Book in Print Encyclopedia of Dinosaurs ed. by Kevin Padian and Philip J. Currie - (not yet rated)

Book in Print The Complete Dinosaur ed. by James O. Farlow, M. K. Brett-Surman, and Robert F. Walters - (not yet rated)

non-technical The Scientific American Book of Dinosaurs ed. by Gregory S Paul (not yet rated)

in-depth textbook The Dinosauria - by David B. Weishampel, Peter Dodson, Halszka Osmolska - paperback - hardcover a bit dated now, but still a great reference on dinosaurs. Be ready for the technical jargon! 3 1/2 star rating

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