Link To Dino News - "Sauropod Skin and Nests"
Link To Introduction to the DinoMorph Project to learn about computer modelling of sauropods
Sauropods
- gigantic quadrupeds
- largest land living animals of all time
- up to 55 tons
- up to 40 or more meters in length (130ft)
- early Jurassic to Cretaceous, but most abundant during Jurassic/Cretaceous transition
2 major families:
Diplodocidae and Camarasauridae
Minor families:
Brachiosauridae, Cetiosauridae, Titanosauridae
Diplodocids:
-skulls long and slender with elongate muzzles
- jaws have slender, peg-like teeth confined to front of mouth
- nostrils were on top of the skull in front of and above the orbits
- long and relatively lightly built bodies
- neck is extremely long with increased number of cervical vertebrae at expense of dorsal vertebrae
- cervical vertebrae have unusually short ribs
- neural spines of cervical and anterior dorsal vertebrae marked by deep "V"-shaped groove
- high spines on sacral vertebrae
- chevrons of caudal vertebrae were considerably modified from typical earlier sauropods, with fore and aft extensions into parallel rods
- tails very long with up to 80 caudal vertebrae
- last 30 - 40 caudal vertebrae little more than elongate rods - "whiplash" - defensive?
- limbs relatively slender
- rib cages deep and narrow
- forelimbs relatively short with humerous to femur ratio .66
- # of wrist and ankle bones reduced
- only 1 or 2 in wrist
- only one in ankle (astragalus)
Camarasauridae
- very different skull from Diplodocids
- short and heavy with blunt snout
- relatively large, spoon shaped (spatulate) teeth along entire length
- nostrils large and located on sides of skull just in front of eyes
- body is neither exceptionally long or heavy
- only 12 cervical vertebrae
- "U"-shaped trough in neural spines extended along 1st 4 dorsal vertebrae
- spines along sacral vertebrae lower and thicker than in Diplodocids
- extensive pleurocoels in cervical and dorsal vertebrae
Camarasaurids (continued)
- stout limbs with typical humerus to femur ratio .70
- 2 bones in both wrist and ankle and elongated foot.
Brachiosaurids
- heaviest land animals of all time
- Brachiosaurus up to 50 tons
- skull and teeth resemble Camarasaurids
- fore-limb very long with humerus to femur ratio greater than 1, so shoulders are higher than hips
- 13 elongate cervical vertebrae and 11 to 12 dorsal vertebrae
- neural spines are low and undivided
- 50 short caudal vertebrae result in short tail
Cetiosaurids
- relatively small sauropods (only 12m long)
- skull similar to Camarasaurids but with longer muzzle
- numerous slender teeth with small spoon-shaped crowns (intermediate between Diplodocids and Camarasaurids)
- 12 cervical and 13 dorsal vertebrae
- neck vertebrae short and lacked development of pleurocoels
- neural spines not divided
- 3 bones in wrist and 2 in ankle
- humerus to femur ratio .66 (same as Diplodocids)
- forked chevrons
- Shunosaurus had a clubed tail
Titanosaurids
- similar to Diplodocids
- procoelus caudal vertebrae
- large # of sacral vertebrae
- armored
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