EARTH 7 Lecture Notes - Lecture 10: Amphicoelias, Dreadnoughtus, Brontomerus
Sauropod novelties:
1. Denser limb bones --> To support lots of weight!
2. Nasal openings on top of skull
3. Necks with at least 12 vertebrae
4. Even smaller heads relative to size
2013 Study:
Sauropods had multiple sets of teeth per socket (up to five in some specimens) which may have
been replaced in as little as every 35 days. Also the teeth were covered in a very thin layer of
enamel. This all suggests that teeth were used to simply clip off abrasive vegetation to swallow
it whole, and replaced frequently once the enamel wore down
Adaptations for long neck (and large size)
1. Hollow spaces in neck vertebrae
a. This made the neck lighter, and likely had other
b. Light bones above, dense bones below
2. Small head
3. Cable of ligaments held up head and neck
4. Must have had huge hearts
- Sauropods probably walked with neck parallel to ground
- Still reason to believe that some sauropods often did have their hands held u high
Shale is weak
Brachiosaurus --? Arm lizard
~ 13m tall = 43ft
~25m long = 80ft
Titanosaurians - worldwide distribution in Late Jurassic and Cretaceous
These appear to have replaced other sauropods that began to die out in the Late Jurassic and
early Cretaceous
Include some of the largest of all sauropods (beside amphicoelias)
Dreadnoughtus - a newly described (Sept. 14) Late Cretaceous Titanosaurian from Argentine
Patagonia. The largest well-known land vertebrate yet described.
Why so big?
- Larger size → can subsist on low quality food
Scaling Problems in Sauropods
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Sauropod novelties: denser limb bones --> to support lots of weight, nasal openings on top of skull, necks with at least 12 vertebrae, even smaller heads relative to size. Sauropods had multiple sets of teeth per socket (up to five in some specimens) which may have been replaced in as little as every 35 days. Also the teeth were covered in a very thin layer of enamel. This all suggests that teeth were used to simply clip off abrasive vegetation to swallow it whole, and replaced frequently once the enamel wore down. Sauropods probably walked with neck parallel to ground. Still reason to believe that some sauropods often did have their hands held u high. Titanosaurians - worldwide distribution in late jurassic and cretaceous. These appear to have replaced other sauropods that began to die out in the late jurassic and early cretaceous. Include some of the largest of all sauropods (beside amphicoelias)
