Diplodocids, or members of the family Diplodocidae, are sauropod dinosaurs such as the Diplodocus and the Apatosaurus. The family includes some of the longest creatures ever to walk the earth, including the Supersaurus, and the Seismosaurus, which might have reached lengths of up to 40 m (130 ft.). Families Brachiosauridae Camarasauridae Cetiosauridae Diplodocidae Euhelopodidae Nemegtosauridae Titanosauridae Vulcanodontidae Sauropoda, the sauropods, are a suborder or infraorder of the saurischian (lizard-hipped) dinosaurs. ... Orders Saurischia    Sauropodomorpha    Theropoda Ornithischia Dinosaurs are animals that dominated the terrestrial ecosystem for over 100 million years. ... Species (Hatcher, 1901) (Holland, 1924) (Marsh, 1878; holotype) Diplodocus ( Latin: double-beam) is a type of dinosaur of subgroup Sauropoda. ... Species Apatosaurus ajax Apatosaurus excelsius Apatosaurus louisae Apatosaurus, formerly known as Brontosaurus, is a genus of sauropod dinosaurs that lived about about 140 million years ago, during the Jurassic period. ... Species (Jensen, 1985) Supersaurus was discovered in a Colorado rock formation in 1972. ... Species Seismosaurus, meaning Earth-shaking lizard, is one of the giant sauropods of the late Jurassic period. ... The metre, or meter, is the basic unit of length in the International System of Units (SI: Système International dUnités). ... This article is about a foot as a unit of length. ...

While still massive, when compared to the titanosaurids and brachiosaurs, the diplodocids were relatively slender but extremely long. They had short legs, making them the "dachshund" of giant dinosaurs; and their rear legs were longer than than front legs, giving their back a distinctive downward slope towards the neck. Genera Aegyptosaurus Andesaurus Antarctosaurus Argentinosaurus Argyrosaurus Bruhathkayosaurus Paralititan Saltasaurus Titanosaurus A titanosaurid (or more informally, a titanosaur) is a member of the family Titanosauridae, which is composed of sauropod dinosaurs such as the Saltasaurus and the Titanosaurus. ... Species (type) For many decades, Brachiosaurus (brack-ee-oh-SORE-us) was the largest dinosaur known. ... Country of origin Germany Classification Breed standards (external links) The Dachshund is a short-legged, elongated dog breed of the hound family. ...

A diplodocid was recently found with a row of keratinous (horny, not bony) spines running down its back. Since dermal tissue is rarely preserved in the fossil record it is not known how widespread the feature is, but sails may be a common feature among diplodocids. Horn may refer to: horn (anatomy), a hollow, pointed projection of the skin of various animals Horn, Austria horn (diacritic), a diacritic mark used to indicate that a normally rounded vowel such as o or u is to be pronounced unrounded horn (instrument) horn, a slang term for any wind... A fossil Ammonite Fossils are the mineralized remains of animals or plants or other traces such as footprints. ...

Their necks were also extremely long, and according to recent computer simulations they may not have been able to lift their necks like other sauropods. Instead of reaching up into trees, they may have used their necks to graze over a broad area. They may also have used their necks to reach into dense stands of conifers, or over marshy ground. Alternatively the whole of the body was raised by standing on the hind legs or by resting the front legs on some hillock. A computer simulation or a computer model is a computer program which attempts to simulate an abstract model of a particular system. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers, division Pinophyta, are one of 13 or 14 division level taxa within the Kingdom Plantae. ... In geography, a marsh is a type of wetland, featuring grasses, rushes, reeds, typhas, sedges, and other herbaceous plants (possibly with low-growing woody plants) in a context of shallow water. ...

Like other sauropods, their heads are tiny with the nostrils on the top of the head, but unlike other sauropods they have a long, sloping snout. Their teeth are only in the front of their mouth, and look like pencils or pegs. They probably used their teeth to crop off food, without chewing, and relied on gastroliths (swallowed stones) to break down tough plant fibers (similar to the way modern birds swallow gizzard stones). Types of teeth Molars are used for grinding up foods Carnassials are used for slicing food. ... Gastroliths (gizzard stones) are rocks which are usually found in association with fossils of herbivorous animals thought to lack teeth, such as birds or, further in the past, dinosaurs. ... Divisions Land plants (embryophytes) Non-vascular plants (bryophytes) Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants Adiantum pedatum (a fern... Orders Many - see section below. ... The gizzard is a very muscular stomach that is found in birds, earthworms, and other animals. ...

Diplodocids also have a long, whip-like tail. It is thick at the base, and tapers off to be very thin at the end. Computer simulations have shown that the diplodocids could have easily snapped their tails, like a bullwhip. This could generate a sonic boom in excess of 200 decibels, and may have been used in mating displays, or to drive off predators. There is some circumstantial evidence supporting this as well: A number of diplodocids have been found with fused or damaged tail vertebrae (bones in the spine), which may be a symptom of cracking their tails. This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... A bullwhip is a single-tailed whip, usually made of braided leather, which was originally used as a farmers tool for working with livestock. ... When an aircraft breaks the sound barrier, an unusual cloud sometimes forms in its wake. ... Although it is widely used as a measure of the loudness of sound, the decibel (dB) is more generally a measure of the ratio between two quantities, and can be used to express a wide variety of measurements in acoustics and electronics. ... A diagram of a thoracic vertebra. ...

The Amphicoelias genera, which includes the rather dubious but spectactularly long Amphicoelias fragillimus, may also be a member of this family; but is usually classified as an incertae sedis (unknown) member of the parent clade, the Diplodocidimorpha. Not enough is known about the genera to classify it more precisely. Binomial name Amphicoelias fragillimus Cope, 1878 Amphicoelias fragillimus (pronounced AM-fee-SEEL-ee-as fra-JIL-i-mus, and meaning very fragile double cavities) may be the largest dinosaur ever discovered. ... Greek clados = branch) or phylogenetic systematics is a branch of biology that determines the evolutionary relationships of living things based on derived similarities. ...

External links

• Cracking the whip, from the NewScientist.
• Ivan Peterson's Whips and Dinosaur Tails.
• The Dinosauricon's cladogram of Diplodocidae.