Melton Wold Fossil

Bradysaurus was a group of extinct early reptiles found in South Africa. An ancient group of animals with massive bodies, strong limds and huge groteque skulls.

"These animals roamed on the landscape that is today known as the Karoo more than 250 million years ago. 250 million years ago the Earth looked very different to today. What we recognise as the dry and arid Karoo was once a vast inland sea. Over time the sea slowly dried up and all that remains of that sea are fossils of the animals that lived along side its waters (like bradysaurus) and the sand and mud that has now turmed to sandstone and mudstone over time.
The rocks of the Karoo preserve a world class assemblage of fossils which show the early evolution of tortoises, dinosaurs and mammals. This is the only place in the world where such an extended fossil record of early evolution of “reptilian” life is preserved in a single place, a place that stores fossil treasures that show the most distant evolutionary ancestry of mammals in remarkable detail. The Karoo is a treasure chest of information about our ancient past and hold many secrets waiting to be uncovered." - Dr. Merrill van der Walt, WITS 21st Century, Institutes “Towards Global Top League Status”, Postdoctoral Fellow: Evolutionary Studies Institute (ESI)
Palaeosciences Centre 


STONE BONES of the ancient Karoo
Two hundred and fifty million years ago all the continents had come together into a single land area known as Pangea. This was a time, some 50 million years before the dinosaurs, when strange animals known as mammal-like reptiles ruled the land. From delicate mole-like burrowers to fat cow-sized grazers to terrible predators with slashing teeth, these animals were locked in an interwoven web of predator and prey. Over millions of years one group of these mammal-like-reptiles evolved into the first mammals. Yes, one of these creatures was the ancestor to all mammals, including us! All the mammal-like reptiles became extinct around 200 million years ago and if we had not discovered their fossilized remains in the rocks of the South African Karoo, we would never have known that they had ever existed. Palaeontologists who study these fossils are like detectives at the scene of a crime. They collect evidence from the skeletons and surrounding rock to reconstruct how they lived and died. The Karoo fossils shown here were collected from outcrops on Melton Wold by Iziko South African Museum palaeontologists. They all date back to the late Mid-Permian period around 260 million years ago.











SCAVENGER OF THE ANCIENT KAROO 
This very rare skull of a carnivorous gorgonopsian was found on Melton Wold in 2016 by Dr Eric Harley whilst prospecting with a group of Friends of Iziko South African Museum led by Prof. Roger Smith. The skull was prepared in the Iziko Karoo palaeo-laboratory in Cape Town and then an exact replica was made by skilled technicians in the casting laboratory of the Wits Evolutionary Studies Institute, Johannesburg. With only fossil skeletons to look at it is difficult to tell whether an animal was an active predator (hunted other animals) or primarily a scavenger (ate the meat off dead animals) or on perhaps both. It does seem likely that because so many different kinds of carnivorous mammal-like reptiles lived at the same time they had different feeding habits much like lions, hyenas, wild dogs and mongoose in East Africa today. This skull is from a scavenging mammal-like reptile known as Eriphostoma microdon. Armed with a set of sharp interlocking front teeth (incisors) and two stabbing serrated canines they would sink them into the tough leathery skin of the dead animal then with powerful jaw-closing muscles and twisting their head side to side, they would tear off chunks of flesh which were swallowed with very little chewing. There are only 14 fossil skulls of this animal that have ever been found, which is why it is necessary to keep the prepared fossil safe and sound in a National Museum Collection. Scientists still do not know what the rest of the body looked like, which is why they are still looking for more complete skeletons.


DIICTODON The “dassie” of the ancient Karoo
Diictodon (meaning 2 pointed teeth) was the most common small herbivore on the ancient Karoo floodplains. Looking like a hairless tortoise-beaked dassie, these strange animals were very well adapted to life underground. They lived in communal groups of 10 or more in a “township” of underground burrows. They rarely wandered far from their burrows during daylight for fear of being stalked by the much more fleet-footed gorgonopsians. At night they would have been able to forage safely in the riverbank undergrowth, using spade like claws on the front feet to dig for roots and rhizomes, then slicing off chunks with their horny beak. As Diictodon infants grew up, their skulls not only got larger but also changed shape depending on their gender. Roughly half of the Diictodon skulls between 5 and 12 cm long have canine tusks and the rest are tuskless. Scientists believe that the tusks were most likely used by male Diictodon for fighting and as a visible display of prowess when competing for mates within the community.
 
 
 
 
 
 
 
 
 
 
 
 
LUMBERING OLD “stuck in the mud”
Fossilised skeleton of Bradysaurus (meaning “robust reptile”), a lumbering hipposhaped herbivore that roamed the ancient Karoo plains 260 million years ago. It is a pareiasaur (meaning “reptile with cheek armour”) which were a group of rather bulky land animals that colonized all the lowlands of Pangea from 265-253 Mya. They can be easily recognized by the two flared-out extensions of the skull roof which resemble the helmets worn by ancient Greek gladiators. Small but distinctively multi-cusped teeth and round bony plates (osteoderms) embedded in the skin are other distinguishing features. The animal looks ungainly because of its barrel-shaped body and short elbows-out legs. However, the elongated vertically-positioned shoulder blade and pelvis confirm that the legs are in the right place and the large belly was held off the ground. Many of the Bradysaurus skeletons we find are preserved in a standing-up position (like this one), with their legs going down into the rock. The blunt leaf-shaped teeth suggest that Bradysaurus generally preferred to graze on the soft, lush vegetation around ponds and lakes. This could explain why they commonly got stuck in soft mud and died standing up. A Bradysaurus fossil laid out in concrete can be seen in the veld approximately 7 km from the guest house.
 
 
 
 
 

 
 
                                                                                        Bradysaurus on the RSA 8c stamp, 1982.