page_title: Diplodocidae
section_title: Description
hierarchical_section_title: Diplodocidae / Description
caption_attribution_description: Diplodocus longus
context_page_description: Diplodocids, or members of the family Diplodocidae, are a group of sauropod dinosaurs. The family includes some of the longest creatures ever to walk the Earth, including Diplodocus and Supersaurus, some of which may have reached lengths of up to 34 metres.
context_section_description: While the diplodocids were massive sauropods, they were relatively slender when compared to the titanosaurs and brachiosaurids, although they were also extremely long. They had short legs, making them the "dachshund" of giant dinosaurs, and their rear legs were longer than front legs, giving their back a distinctive downward slope towards the neck.
  Their necks were also extremely long. According to recent computer simulations, they may not have been able to lift their necks like other sauropods. However, these simulations do not take vertebral cartilage into account, which would likely allow a greater range of motion. 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.
  Their heads, like those of other sauropods, were tiny with the nasal openings on the top of the head (though in life the nostrils themselves would have been close to the tip of the snout).
  The heads of diplodocids have been widely depicted with the nostrils on top due to the position of the nasal openings at the apex of the skull. There has been speculation over whether such a configuration meant that diplodocids may have had a trunk. A 2006 study surmised there was no paleoneuroanatomical evidence for a trunk. It noted that the facial nerve in an animal with a trunk, such as an elephant, is large as it innervates the trunk. The evidence suggests that the facial nerve is very small in diplodocids. Studies by Lawrence Witmer (2001) indicated that, while the nasal openings were high on the head, the actual, fleshy nostrils were situated much lower down on the snout.
  Diplodocids also had long, whip-like tails, which were thick at the base and tapered 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, which may be a symptom of cracking their tails.
caption: Diplodocus, depicted with spines limited to the mid-line of the back
exif: {"Image Orientation": "Horizontal (normal)", "Image XResolution": "300", "Image YResolution": "300", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS Windows", "Image DateTime": "2007:10:25 22:44:14", "Image ExifOffset": "162", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "3464", "EXIF ExifImageLength": "2204"}