EASC 103 Test 5

Sauropod characteristics

• long neck and tails

• Gigantic size

• Small head size relative to their bodies

• Pneumatic vertebrae

• Air-sac system

• Peg-like / spatulate teeth

• Dorsally located nasal openings

• Pillar like legs with clawed pedal digits 1-3 (sometimes 4)

Types of air-sac systems

• abdominal air sac

• Cervical air sac

• Clavicular air sac

• Lungs

How did dinosaurs get so big?

Their hollow bones made them lighter and made their bones stronger. This made it better to hold the body up against gravity. When sauropods got larger, other dinosaurs did too to keep up with them

Types of sauropod teeth

Peg-like (ex. Apatosaurus and Diplodocus)

Spatulate (ex. Camarasaurus)

Sauropod nasal opening

Are located dorsally. The nares are located right in front of the eyes/orbit

Sauropod rearlimbs

• pedal digits 1-3 (and sometimes 4) have claws

• Their digits curve away from the midline

Sauropod forelimbs

• have a crescent shaped manus

• Have a very large claw on digit 1

• Some titanosaurs don’t have phalanges and walk on their metacarpals

Steps to how sauropods make nests

1. Use pes to make a pit

2. Lay eggs in pit

3. Put leaves and sediment to incubate the eggs OR use the earth’s core to keep the eggs warm

4. Would stand around to protect nesting site

Barapasaurus

“Big leg lizard” that is a basal sauropod from Early Jurassic India. It’s 14m long with most being neck & tail, which makes it a relatively small sauropod

Golden Age of Dinosaurs

The Late Jurassic (150Ma) at the Morrison Fm which is a rich fossil area in the states. Had the most abundant and diverse dinosaurs during this time

Diplodocus

• “Double beam” because the chevrons flatten to beams at the middle of the tail and disappear at the end of the tail

• have long, slender skulls and slender, peg-like teeth

• Have long necks and extremely long whip-like tails

• Relatively lightweight

• Has more horse-like skulls

Dippy

A famous Diplodocus that resides at the Natural History Museum in London.

Dwarf sauropods

Characterized by relatively short necks and smaller body size

Ex. Amsrgasaurus and Nigersaurus

Amargasaurus

9-10m in length with crazy neural spines. Around the size of Carnosaurus or an Allosaurus. Lived in Argentina ~125Ma Earth Cretaceous

1 metric tonne in kg

1000kg