The Sunday News
THE Museum at 50 has seen a joint effort by the staff of the department of geology, palaeontology and other departments to publicise the geology department through articles. We are confident that those who are interested in dinosaurs, nature and the earth, will be impressed by this special article. The Department of Geology is indeed the oldest department within the Natural History Museum. In fact, the Natural History Museum was established (1964) on the basis of its geology collections. The first geology gallery, The Mennel Gallery, was named in honour of the first geology keeper, Mr F P Mennel, who set a high standard in his contributions to the knowledge of geology in Zimbabwe, of which the subsequent ‘‘keepers’’ of geology have also maintained. The geology galleries represent samples of meteriorite, volcanic and natural rocks, minerals, precious stones, fossils of ancient animals, including wood fossils, Stone Age tools, the skeletal material of small early Jurassic theropod (Syntarsus non coelophysis dinosaur,) from the Chitaki River north central Zimbabwe. Dinosaurs are among the most significant prehistoric animals discovered in the country, and Zimbabwe has a well preserved record of prehistoric life forms for both flora (plants) and fauna (animals).
Fossil remains of dinosaurs are now well known in Zimbabwe and they come from several localities. Dinosaurs became extinct 270 million years ago but they continue to fascinate us. Many dinosaur fossils have been discovered from Zimbabwe and studies of the dinosaur fossils tell us how they were buried, fossilised and how the environment has changed through time. Combined research projects of geology-palaeontology provide the best opportunities for truly understanding the ancient world of the dinosaur.
Dinosaurs
Dinosaurs descended from a reptile Triassic group called Theco donts which also gave rise to crocodiles, flying reptiles and birds. They evolved from the same ancestor and split into two groups, the ornithischians and saurischians. Dinosaurs were either quadripedal (four legged) or bipedal (two legged) but became extinct leaving no descendants. Fortunately, a great number of these bones have found their way into the Natural History Museum of Zimbabwe collection since their early discoveries. Hence, there is a remarkable exhibit of dinosaur bones in the geology gallery in the museum.
The first dinosaurian bone in Zimbabwe was found in 1914 in the Bubi district and was assigned to the species Theconontosaurus skirtopodus. More sites were found during the first half of the 20th century in the Nyamandlovu and Madubisa mudstones around Hwange Bubi district. Some of these species which were discovered brought the country to the attention of the scientific world. Other remains were found in the Zambezi Limpopo Karoo basins which include diverse dinocephalian fauna, the skeletal material of the small Early Jurassic theropod dinosaur, Coelophysis rhodesiensis (formerly Syntarsus rhodesiensis) by Dr Mike Raath in 1965 through detailed excavations in Nyamandlovu. More excavations and interpretations of fossils were made, the extraordinary footprints from Chiwore Safari Area and sauropod dinosaurs have been found in the Kadzi River in the Dande Communal Lands, are on display at the Natural History Museum. This special edition of Zimbabwean giant carnivores, herds of horned and plant eating dinosaurs leads people to understand the earth’s history systematically, providing us with information about specific material in the museum.
Coelophysis rhodesiensis
The species coelophysis was a small to medium size, lightly built and bipedal carnivore that could grow up to 3 metres. It was thought to have been covered with feathers which would protect it from harsh desert temperatures. The specimen QG165 (coelophysis rhodesiensis) exhibited at the Natural History Museum Bulawayo is part of a skeleton that was recovered from a bone-rich deposit in the Early Jurassic fine-grained Forest Sandstone Formation in the Chitaki River, north-central Zimbabwe.
This small carnivorous dinosaur was discovered in 1963 by a group of boys from Northlea High School Bulawayo, under the direction of their teacher Mr Ian K Stewart. They came across a partially exposed fossil in the Forest Sandstone at Southcote Farm in Nyamandlovu District of Zimbabwe and since then, the area has been visited several times.
Massospondylus
These were large animals of about three to five metres long and one of the most widespread early dinosaurs. They were the most common dinosaur in Zimbabwe. They were plant eaters, and ate tough leaves. Remains of Massospondylus harriesi and Massospondylus carinatua are also housed in the Natural History Museum Bulawayo.
Massospondylus harriesi
The specimen bones were discovered by Mr T Tossup in January 1953 from Southcote Farm Nyamandlovu and remains have been found in Mana Pools. The genus Massospondylus has been described on the basis of well preserved material from Zimbabwe. Massospondylus is currently recorded from South America, Southern Africa and the Yunnan region of southern China and thus providing evidence that Southern China may have formed an integral part of Gondwanaland, enabling the free movement of animals.
Massospondylus carinatus
The bone materials which include the greater part of the left side of the Pelins and almost complete left hind leg and foot bones were excavated in situ in 1931 in Chelmer Spruit on Chelmer farm in the Nyamandlovu district as well as Chitake River Sentinel Ranch.
Vulcanodon
The Vulcanodon was a strange animal that was described and named in 1972. This dinosaur was first discovered in 1969 on an island in Lake Kariba, and this species has only been discovered in Zimbabwe. The dinosaur was about 6,5 metres long.
Brachiosaurus
This four footed herbivorous dinosaur was one of the largest and heaviest dinosaurs on earth and it existed during the Jurassic and Cretaceous times. The dinosaur was discovered near Kadzi River in the Dande Communal Lands in 1965. Other specimens of this dinosaur have also been found in the United States. The best skeletons were collected earlier in the past century in Tanzania.
Allosaurus
When dinosaurs and other animals step into soft sediments they leave impressions we call footprints. Foot prints attributed to Allosaurus were recovered on Forest Sandstone blocks. The first dinosaur trackway was found in Zimbabwe in Ntumbe river bed about five kilometres due Chenje airstrip in Chewore Safari area. Chewore trackway is the longest and one of the best preserved dinosaur trackways in Africa. These were discovered mid 1984 by Mr Mike Aldersey, an Australian hunter.
Senior geologist Mr T Brodrick of the Geological Department carried out the investigation and discovered fourteen clearly exposed footprints on the Sandstone pavement after excavations were carried a total forty-five footprints including the fourteen already exposed. Thirty two moulds were made and these are housed in the paleontological collection at the Natural History Museum Bulawayo. There were no signs of tail drag impressions observed, the trackway maker was habitual bipedal i.e. (walked on two legs). It is very likely that this dinosaur belonged to the Allosaurus, a carnivore.
The reason for the dinosaur extinction is not clear although diseases, sudden climate change, environmental change may have brought about their end. Although these remains are detached pieces (bones are usually found alone with no apparent association of bones from an individual skeleton) they are of great international significance.
The museum also contains a remarkable representative collection of dinosaur bones in the collections storerooms. Besides the museum, the main contributors in the quest for dinosaurs are the geologists at the University of Zimbabwe, the Geological Survey Department and Private Companies. Apart from the important scientific research it has carried over the years, the Natural History Museum has played an important part in the economic development of the country and in contributing to the knowledge of its geology. Though very many historical items are threatened or in danger of extinction through environmental destruction and are regarded as unimportant. The National Museum is keen to extend the scope of the dinosaur exhibits and therefore appeals to the mining companies, the individuals to assist them and the society to recover and preserve any dinosaur fossils which so often otherwise find their way to the dumps.
