Scientists have uncovered an enduring mystery, discovering what sauropods look like brontosaurus i Diplodocus – they rested their gigantic bodies on the ground.
A team led by the University of Queensland and Monash University used engineering and 3D modeling methods to digitally reconstruct and test the function of different sauropod foot bones.
Dr Andréas Jannel, who carried out the research during his PhD studies at UQ’s Dinosaur Laboratory, said the team found that the sauropod’s hind feet had a soft tissue pad under the “heel”, that cushioned the foot to absorb its immense weight.
“We have finally confirmed a long-suspected idea and provided biomechanical evidence that a soft tissue pad would have played a crucial role in reducing locomotor pressures and bone stresses,” said Dr. Jannel.
“It’s mind-boggling to imagine that these giant creatures could have supported their own weight on earth.”
Sauropods were the largest land animals that roamed the Earth for over 100 million years.
They were first thought to be semi-aquatic with the buoyancy of water supporting their massive weight, a theory disproved by the discovery of sauropod tracks in terrestrial deposits in the mid-20th century.
Monash University Dr. Olga Panagiotopoulou he said that sauropods were thought to have feet similar to those of a modern-day elephant.
“Popular culture, think Jurassic Park or Walking with Dinosaurs, often depicts these giants with almost cylindrical, thick, elephant-like feet,” Dr Panagiotopoulou said.
“But when it comes to their skeletal structure, elephants are actually ‘toes’ on all fours, while sauropods have different foot configurations on their front and hind feet.
“The front feet of sauropods are more columnar, while they have more ‘high wedge heels’ in the back supported by a large soft tissue pad.”
UQ Associate Professor Steve Salisbury said this was because sauropods and elephants had different evolutionary origins.
“Elephants belong to an ancient order of mammals called proboscideans, which first appeared in Africa approximately 60 million years ago as small, nondescript herbivores,” Dr Salisbury said.
“In contrast, sauropods, whose ancestors first appeared 230 million years ago, are more closely related to birds.
“They were agile, two-legged herbivores and only later in their evolution did they walk on all fours.
“Crucially, the transition to becoming the largest land animals to walk on land appears to have involved the adaptation of a heel pad.”
The researchers now plan to use 3D modeling and engineering methods to make further discoveries.
“I am interested in applying a similar method to a whole limb and including additional soft tissues such as muscles, which are rarely preserved in fossils,” said Dr Jannel.
“We are also excited to study the limbs and feet of other prehistoric animals.
“This should allow us to answer different questions about the biomechanics of extinct animals and better understand their environmental adaptations, movement and lifestyle.”
Read the full paper in Science Advances.
More pictures and videos here
Top left image: Dr Andreas Jannel. supplied
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