Diplodocus Size Comparison
Diplodocus 3D Viewer pairs published D. carnegii sauropod figures with a 1.8 m person on screen - length about 24-26 m (Size vs human uses about 25 m), weight about 12-14.8 tonnes (about 13.5 tonnes on the facts panel), and era 152-149 Mya - so the long-tailed scale gap stays readable at a glance.
Diplodocus published figures
The Diplodocus facts panel and this table disclose published ranges rather than one invented single number; the Size vs human control uses about 25 m as the length scale ratio:
| Measure | Figure | Vs a 1.8 m person |
|---|---|---|
| Length | about 24-26 m (D. carnegii reference specimen); Size vs human uses about 25 m | ~13.9x a person end-to-end at the 25 m scale figure |
| Height | about 4.5 m (model heightM used by the scene) | ~2.5x adult standing height |
| Weight | about 12-14.8 tonnes (D. carnegii); facts panel uses about 13.5 tonnes / 13500 kg | sources disagree by study - shown as a range with one representative point |
| When it lived | 152-149 million years ago | Kimmeridgian, Late Jurassic; herbivore; named by Othniel Charles Marsh in 1878; D. carnegii described by John Bell Hatcher in 1901; CM 84 specimen from Sheep Creek, Wyoming (1899) |
How the Diplodocus size-vs-human toggle stays honest
The Diplodocus model is drawn to a fixed on-screen length so it fits the canvas; the Size vs human control then places a 1.8 m person at the true length ratio used by the viewer (about 25 m). Tap Size vs human under the canvas to show or hide the scale figure - the comparison is proportional, not a decorative sticker. Published length still spans about 24-26 m for D. carnegii, so the toggle picks one clear scale inside that disclosed range. The shared sauropod builder does not use tallForelimbs, so the silhouette stays the long-necked, long-tailed horizontal body rather than a giraffe-like raised forelimb stance.
What a person would see beside a Diplodocus
What a person would see is a quadrupedal sauropod whose body length at the 25 m scale dwarfs a 1.8 m adult end-to-end, with a long neck and a counterweight tail that can hold about 80 caudal vertebrae in published reconstructions - turn on the person in the viewer and orbit beside a hind leg to feel how the horizontal-back posture and whip-like counterweight tail sit relative to the scale figure. Skin and color are an artistic reconstruction, not a fossil-accurate skeleton. Click head, neck, body, leg, or tail in the viewer for the fossil facts tied to those parts.
What the Diplodocus size numbers are not
What these size numbers are not is a claim of one precise length or weight beyond the cited D. carnegii range: the Diplodocus size comparison discloses about 24-26 m and about 12-14.8 tonnes and uses about 25 m / 13.5 tonnes only as representative points inside those ranges; it does not invent soft-tissue or color accuracy, no free-licensed Diplodocus glTF is re-hosted yet so the viewer stays procedural, and this is not a win/lose game. For the control walkthrough see how to view Diplodocus in 3D. For trade-offs versus phone AR apps see Diplodocus 3D viewer vs AR apps.
Other dinosaurs to compare
Other dinosaurs in the collection make useful size comparisons too: Diplodocus is a Late Jurassic sauropod (D. carnegii reference from Sheep Creek, Wyoming), so for a taller giraffe-like sauropod see the Brachiosaurus 3D Viewer and its published-figures comparison, or for another Late Jurassic herbivore closer to the ground see the Stegosaurus 3D Viewer.
Frequently asked questions
Can you rotate and zoom the Diplodocus model yourself, or does it just auto-play?
Drag to orbit and use the scroll wheel or a pinch gesture to zoom in the Diplodocus 3D Viewer; a separate toggle turns automatic rotation on or off, another toggles idle motion, and a Fullscreen button expands the canvas - all independent of the Size vs human control described above.
What happens if you click on an empty area instead of a body part?
Clicking an empty area next to the model closes whichever body-part fact is showing and brings back the general Diplodocus fact sheet - length, weight, era, and diet - rather than leaving a single part's note on screen.
Is the tail's whip-crack sound a proven fact?
No - the whip-like tail is built from about 80 caudal vertebrae with double-beamed chevron bones, but whether it could crack like a whip for defense or signaling is a proposed hypothesis in the paleontology literature, not a settled fact. The copy and viewer both present it that way rather than as confirmed behavior.
What did Diplodocus eat, and how do its teeth show that?
Diplodocus was a herbivore with small, forward-pointing peg teeth suited to stripping leaves from branches in one direction rather than chewing them - a distinct feeding method from a broad, grinding dentition.
Does viewing the Diplodocus model send anything to a server?
No - the viewer renders entirely in the browser using WebGL. Rotating, zooming, toggling Size vs human, and clicking parts all happen client-side; there is no account, no upload, and nothing about the visit is sent to a server to generate the model or the facts panel.
Where do these Diplodocus size figures come from?
The length, weight, and era ranges are drawn from Wikipedia's synthesis of the published paleontology literature for the D. carnegii reference specimen, which is also why the figures are shown as ranges - about 24-26 m and about 12-14.8 tonnes - instead of one invented precise number.
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