One group of plant-eaters grew to become the biggest land animals ever. These were the sauropods – impressive long-necked, four-legged giants.
However, the ‘club’ has expanded to include the dwarfed, the short-necked, the sail-backed and the armoured. Membership is no longer just about size. Despite this, it is the ‘super heavyweight’ status of some sauropods that continues to captivate us. Why did some grow so big?
The suggestions include:
- A stable and warm climate resulted in an abundance of plants.
- The abundance of plants meant sauropods could eat large amounts of food.
- A massive gut was required to break down tough plant material. A big body was needed to support this gut.
- Being big is a useful adaptation. Adult sauropods were a challenge for predators (although you will meet some who still attacked them).
- A large body could maintain a constant body temperature. This helped reduce overheating in hot weather and loss of heat in cold weather.
Did you know?
Titanosaurs are a group of sauropods that include the largest-ever dinosaurs like Titanosaurus, Argentinosaurus and Paralititan, and the Australian Austrosaurus. They are primarily found in Gondwana.
Some examples of sauropods worldwide include:
- Europasaurus holgeri – Germany, 156–151 million years ago
- Shunosaurus lii – China, 168–161 million years ago
- Brachytrachelopan mesai – Argentina, 151–146 million years ago
- Brachiosaurus altithorax – USA, 156–146 million years ago
- Amargasaurus cazaui – Argentina, 146–125 million years ago
- Argentinosaurus huinculensis – Argentina, 112–89 million years ago
New evidence shows that there were ‘dwarf’ sauropods. Europasaurus holgeri grew to only six metres long. It lived in Germany when this area was a series of small islands. Smaller was better when restricted to small island spaces.
An example of an Australian sauropod is Rhoetosaurus brownei - found in Roma, Queensland, Middle Jurassic, 172–168 million years ago. The leg bones of Rhoetosaurus were adapted to carry a huge body weight. Rhoetosaurus is one of only a few sauropod species discovered in Australia.
Fran Dorey , Exhibition Project Coordinator