Palaeontological Treasures of Karonga
The reconstructed skeleton of Malawisaurus
in Karonga Museum
We all know Karonga as the most northerly town on our lakeshore which recently suffered devastating earthquakes. However, few people know about the amazing dinosaur remains and other fossils discovered in the District. Elizabeth Gomani Chindebvu, Phd, Director of Culture in the Ministry of Tourism, Wildlife and Culture, has first-hand knowledge of the rich and important findings uncovered in 1984.
What are dinosaurs?
Dinosaurs were reptiles that existed many millions of years ago. There was a huge variety of sizes and shapes. Some dinosaurs were giants three times larger than an elephant while others were no bigger than a chicken. They are categorized into two major groups based on their hip structures: bird-hipped dinosaurs and lizard-hipped dinosaurs.
They had different physical features, some of which include claws, feathers and armour on their body. Some dinosaurs were quadrupedal, which means they walked on four limbs, while others were bipedal, meaning they walked on two legs. While some were herbivores (plant eaters), others were carnivores (meat eaters). We can determine what the dinosaurs’ diet was by comparing them with modern animals. Today, herbivores generally have blunt, grinding teeth while carnivores have sharp, biting teeth. Some dinosaurs’ teeth are blunt, so we know they were herbivorous, while others have sharp and serrated teeth and were, therefore, carnivorous.
It is known that dinosaurs were social animals that probably roamed around in herds, wandering over long distances in search of food and other amenities. They laid eggs just as most reptiles do today and must have looked after their offspring in a way similar to crocodiles today.
What are dinosaurs?
Dinosaurs were reptiles that existed many millions of years ago. There was a huge variety of sizes and shapes. Some dinosaurs were giants three times larger than an elephant while others were no bigger than a chicken. They are categorized into two major groups based on their hip structures: bird-hipped dinosaurs and lizard-hipped dinosaurs.
They had different physical features, some of which include claws, feathers and armour on their body. Some dinosaurs were quadrupedal, which means they walked on four limbs, while others were bipedal, meaning they walked on two legs. While some were herbivores (plant eaters), others were carnivores (meat eaters). We can determine what the dinosaurs’ diet was by comparing them with modern animals. Today, herbivores generally have blunt, grinding teeth while carnivores have sharp, biting teeth. Some dinosaurs’ teeth are blunt, so we know they were herbivorous, while others have sharp and serrated teeth and were, therefore, carnivorous.
It is known that dinosaurs were social animals that probably roamed around in herds, wandering over long distances in search of food and other amenities. They laid eggs just as most reptiles do today and must have looked after their offspring in a way similar to crocodiles today.
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How does one know where to look for dinosaurs?
Dinosaurs have been found all over the world. They are normally found in sedimentary rocks (formed by the accumulation of mineral and organic fragments deposited by water, ice or wind) and rarely in low grade metamorphic rocks (transformed by heat, pressure or other natural causes). Igneous rocks (formed from solidified volcanic lava) would have been too hot and would have scorched the bones. Sedimentary rocks are ideal because, as sedimentation is taking place, the sediments bury the bones and prevent scavengers from chewing them. These sediments are from the Mesozoic age, which is generally referred to as the Age of Dinosaurs. The age is determined through dating of the associated rocks in which the dinosaur remains are found. The dating can be relative based on stratigraphic position (position in the rock strata) or absolute based on radiometric dating (a system based on the decay of its constituent radioactive atoms). Absolute dating is the one that provides the age brackets for fossils. Geologists have produced geologic maps indicating what types of rocks are found where. These maps also indicate the ages of the rocks concerned. A palaeontologist (who studies fossils and remains of past animal life) will study these geologic maps to determine the area of research based on the rock type and the age of animals being researched. Having established where the right rocks are found on the map, the palaeontologist will go to the area for a site survey to determine if any fossils are found. Fossils are usually found in the form of bones but can also be in the form of footprints, skin impressions, eggs and items that would indicate the presence of life. Fossils have to be seen on the surface before excavation starts. These fossils could be in place or washed away from uphill. Excavation will only take place where the bones are in place. Before uprooting the bone from the ground, its orientation relative to the north, the depth in the ground where it is found, its length and width are measured. This is because the bones are not always lying in their natural positions and there may be more than one individual in a single excavation pit. These measurements are essential during analysis in determining which bones belong to one individual and what might have happened before the skeleton was buried. The details of the sediments around the skeleton are also recorded to help in interpreting the prevailing deposition conditions at that time. Reconstructing a dinosaur skeleton Having stayed in the ground for millions of years, the fossils are usually extremely fragile and, therefore, need to be handled with care. Consequently, they are plastered (like a broken human limb today) before they are removed from the ground. They are usually collected together with the sediments around them to help cushion the bones.As stated earlier, the fossils are not always found complete. |
 From: Levin, H.L. 1992. The Earth Through Time   Karonga Museum |
When they are incomplete, comparative anatomy is used to determine the position of the bones found and then work out what is missing. Specimens used in this comparative analysis are both from modern animals and also from other fossil specimens that have been found nearly complete. Putting together the bones is like a jigsaw puzzle and requires a great deal of patience!
Fossiliferous rocks of Malawi
The rifting associated with the formation of Lake Malawi also helped to expose the rocks that contain the fossils in Malawi. In the northern part of the Malawi rift lie three rock formations next to each other on the western shore of Lake Malawi, which stretch for more than hundred kilometers from the Songwe River in the north to the Livingstonia-Mchenga areas on the Chiweta Escarpment in the south. One of these sedimentary rock formations is known as the Dinosaur Beds. These sedimentary rocks were mostly deposited by rivers into a kind of basin.
The palaeontological work on dinosaurs in Malawi
The palaeontological work on dinosaurs in Malawi has been carried out by the Department of Culture, particularly the Antiquities Division, in collaboration with International Researchers from Southern Methodist University of Dallas, Texas, USA under the project called “Malawi Dinosaur Project.” This work started in 1984 and has collected a number of fossils. The project has collected at least three species of dinosaurs, three species of crocodiles, turtles, some frogs and fish scales.
Dinosaurs in MalawiHere in Malawi dinosaurs have been found in Karonga District in the Northern Region. The dinosaurs from Malawi are estimated to be from the Cretaceous period between 145 and 97 million years old. The dinosaurs include both plant eaters and meat eaters. The plant eaters are Malawisaurus (after the name of the country plus -saurus, Greek for lizard) and Karongasaurus (after the name of the district where it was found). Malawisaurus, the skeleton mounted in Karonga Museum, constitutes the majority of the fossils collected from Malawi so far.
Relatives of Malawi’s dinosaurs are found in Tanzania, Niger, Madagascar and South America. This is because Africa and South America were once one supercontinent referred to as Gondwanaland. These continents are now far apart because the continents are constantly shifting due to the movement of the tectonic plates within the Earth, which is loosely referred to as the Continental Drift.
The movement of the tectonic plates is also the cause of earthquakes and explains the existence of Lake Malawi. The underlying forces can push these tectonic plates towards one another (compressional forces), common in areas where there are volcanoes, or away from each other (tensional forces), common in areas where there are rift valleys. Malawi lies in an area of tensional forces within the Great East African Rift System. This rifting caused the formation of Lake Malawi and hot springs and was, of course, the reason why Karonga recently experienced a series of frightening earthquakes which, sadly, claimed lives and left many families homeless.
Fossiliferous rocks of Malawi
The rifting associated with the formation of Lake Malawi also helped to expose the rocks that contain the fossils in Malawi. In the northern part of the Malawi rift lie three rock formations next to each other on the western shore of Lake Malawi, which stretch for more than hundred kilometers from the Songwe River in the north to the Livingstonia-Mchenga areas on the Chiweta Escarpment in the south. One of these sedimentary rock formations is known as the Dinosaur Beds. These sedimentary rocks were mostly deposited by rivers into a kind of basin.
The palaeontological work on dinosaurs in Malawi
The palaeontological work on dinosaurs in Malawi has been carried out by the Department of Culture, particularly the Antiquities Division, in collaboration with International Researchers from Southern Methodist University of Dallas, Texas, USA under the project called “Malawi Dinosaur Project.” This work started in 1984 and has collected a number of fossils. The project has collected at least three species of dinosaurs, three species of crocodiles, turtles, some frogs and fish scales.
Dinosaurs in MalawiHere in Malawi dinosaurs have been found in Karonga District in the Northern Region. The dinosaurs from Malawi are estimated to be from the Cretaceous period between 145 and 97 million years old. The dinosaurs include both plant eaters and meat eaters. The plant eaters are Malawisaurus (after the name of the country plus -saurus, Greek for lizard) and Karongasaurus (after the name of the district where it was found). Malawisaurus, the skeleton mounted in Karonga Museum, constitutes the majority of the fossils collected from Malawi so far.
Relatives of Malawi’s dinosaurs are found in Tanzania, Niger, Madagascar and South America. This is because Africa and South America were once one supercontinent referred to as Gondwanaland. These continents are now far apart because the continents are constantly shifting due to the movement of the tectonic plates within the Earth, which is loosely referred to as the Continental Drift.
The movement of the tectonic plates is also the cause of earthquakes and explains the existence of Lake Malawi. The underlying forces can push these tectonic plates towards one another (compressional forces), common in areas where there are volcanoes, or away from each other (tensional forces), common in areas where there are rift valleys. Malawi lies in an area of tensional forces within the Great East African Rift System. This rifting caused the formation of Lake Malawi and hot springs and was, of course, the reason why Karonga recently experienced a series of frightening earthquakes which, sadly, claimed lives and left many families homeless.
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Are dinosaurs still living today?
It depends on whose school of thought one wants to follow. However, it is now generally considered that dinosaurs still live today in the form of birds and that a number of dinosaur species disappeared at the end of the Mesozoic Era around 65 million years ago. The dying out of animal species at a particular time is referred to as Mass Extinction. The question that is often asked is what killed the dinosaurs or how and why did dinosaurs disappear on earth? The dying out of these great animals did not happen in one event but in different frenzies that took vast lengths of time. There are also a number of explanations as to why they died, including climatic change due to intense volcanic activity, meteorite impacts and climatic changes. It is generally considered that all these factors played a role in creating a non-conducive environment for the survival of these dinosaurs. |
 Artist’s impression of the Malawisaurus |
Research team excavating the fossils
