Willem is a wildlife artist based in South Africa. He says "My aim is simply to express the beauty and wonder that is in Nature, and to heighten people's appreciation of plants, animals and the wilderness. Not everything I paint is African! Though I've never been there, I'm also fascinated by Asia and I've done paintings of Asian rhinos and birds as well. I may in future do some of European, Australian and American species too. I'm fascinated by wild things from all over the world! I mainly paint in watercolours. . . but actually many media including 'digital' paintings with the computer!"

We took a look, a few weeks ago, at some of the few dinosaur species known from South Africa. They lived in the early Jurassic, and represent some of the earliest dinosaurs to exist in the world. There are some that are slightly older, from the mid- to late Triassic, known from South America, but generally the dinosaurs took until well into the Jurassic to really start dominating the world. Sadly, the fossil record for dinosaurs in South Africa ends in the early Jurassic, at which time massive volcanic eruptions in the east of the country ejected huge amounts of magma that 'capped' the earlier sediments, after which further sedimentation ended and the interior of the country was uplifted, from which time the region was subjected to erosion rather than further deposition. The rest of the history of the dinosaurs we know from sedimentary rocks laid down after this period in other countries.

So now let us look at some South African dinosaurs that were smaller and fleeter of foot than the previous ones, which were precursors of the 'sauropods' or 'lizard-footed' dinosaurs. I reconstruct all of them here as being covered in proto-feathers or fuzz, since it does appear that this feature was present in very early two-legged dinosaurs of both flesh- and plant-eating types. Much later, this proto-fuzz would evolve into proper feathers. Let us look first at some of the dinosaurs called the theropods or 'beast-footed' critters. These included the two-legged meat eaters, of which the fearsome Tyrannosaurus rex is of course the most famous example. While T-rex existed at the very end of the dinosaurian reign, the South African theropods were there at its start, and were rather more modest.

Megapnosaurus, 'Big Dead Lizard', was somewhat facetiously named. Its fossils were found in early Jurassic rocks in Zimbabwe as well as in South Africa. There are footprints in Zimbabwe from a bit earlier, the Late Triassic, which could have been made by it or something similar. It was quite a small dinosaur, reaching 2.2m/just over 7' in length, and about 13 kg/30 lbs in weight. It was a close relative of the well-known early dinosaur Coelophysis ('Hollow Form') which is known from numerous fossils from America. At first,
Megapnosaurus was classified in the genus Syntarsus until palaeontologists realized that the name had already been used for a beetle. Then some classified it as a different species of Coelophysis but it then proved to have features unique enough to warrant its own genus. Presumably the scientists that gave it its present name were being flippant because of getting fed up with all the name changes, which wasn't our poor Megapnosaurus' fault! It was likely a fast-running catcher of small critters from insects and other invertebrates up to small vertebrates. Its long, slender jaws were furnished with many small, sharp teeth, and its clawed forelimbs could perhaps also be used in catching its prey. Several associated fossils have been found that suggest it hunted in packs. It might have been nocturnal, having quite large eyes. The environment at the time was a large floodplain, inhabited by the proto-mammals, early crocodiles, a variety of ancient lizard-like reptiles, and other dinosaurs. Megapnosaurus could reach the age of seven years, and its growth rate appears to have been variable, dependent on food and external circumstances.

Dracovenator ('Dragon Hunter') was a relative, but rather bigger and more robust, reaching 6.5 m/about 22' in length, and 250 kg/550 lbs in weight. Its fossils and name came from the Drakensberg Mountains, or 'Dragon Mountains', of South Africa. It is known from a skull that is similar to that of the dinosaur Dilophosaurus, famous from the Jurassic Park movies. That one had a pair of thin, side-by-side bone crests running along its snout and head, and Dracovenator might have had them as well although no crests have been preserved. It lived in the same kind of floodplain environment, and likely preyed on some of the larger herbivorous dinosaurs of the time and place.

The next four dinosaurs are all from the other branch of the dinosaur family tree, namely the Ornithischians or 'bird-hipped' dinosaurs, which include the well-known Stegosaurus, Ankylosaurus, Iguanodon and Triceratops. The very early origins of this group is still a paleontological puzzle, but the ones known from South Africa are some of the oldest, and indeed South Africa has the greatest diversity of early ornithischian fossils in the world. All of these were small, bipedal, fast-running types.

Eocursor ('Dawn Runner') was one of the most primitive of ornithischians ever found, and represented by quite ample fossil remains. Though much shorter than its hind legs, its front legs had comparatively large, grasping 'hands'. It was about 1m/yard in total length. It had small, triangular teeth packed tightly into its cheeks but smaller, pointed teeth further to the front of its jaws, which means it might have eaten both plant and animal material. All later ornithischians were as far as we can tell, strictly vegetarian.

Lesothosaurus ('Lesotho Lizard') was, if you can't tell, found in the small country of Lesotho which is entirely enclosed inside South Africa. Being similarly primitive to Eocursor, it also might have been somewhat omnivorous. Its teeth were small and suited to nipping and nibbling small food items, while the front of its jaws were toothless and likely covered by a horny beak. It might have had lips and cheeks that covered its teeth when its mouth was closed. It ranged from 1 to 2 m/yards in length, and might have lived in groups. The environment at the time appears to have been quite arid at the time, but nevertheless a diverse assemblage of critters lived there, including ancient amphibian types, proto-mammals, lizard like things, turtles, and other related small, ornithischian dinosaurs.

Heterodontosaurus ('Different-tooth Lizard') was another ancient ornithischian very well-known to science. Its teeth were differentiated into small, nipping front teeth, a pair of long, sharp canine-like teeth in both upper and lower jaw, followed by chisel-like cheek teeth. The 'canines' in its lower jaw were much larger than those in the upper, and both had serrated (saw-blade like) edges. The front of its jaws was covered in a horny beak. It might have been omnivorous, or perhaps already specialized more for eating plants. Compared to Lesothosaurus, it had larger hands more capable of grasping. Its back was stiffened by bony tendons, but its tail was more flexible. Uniquely as far as we know for ornithischians, it had 'belly ribs' or gastralia protecting the underside of its body. It reached about 1.75 m/5'9" in length, and 10 kg/22 lbs in weight. Related species were found to have long, upright bristle-like structures on the upper surface of their tails, so this one might have had them as well.

Lycorhinus ('Wolf Snout') was first identified as a dog-like protomammal, because of its 'canines', which were even longer than those of Heterodontosaurus. It reached 1.2 m/4' in length. Apart from it, and Heterodontosaurus, several other related dinosaurs are known from the time and place. It may have been that they diversified into different diets and lifestyles to avoid competition.

That wraps up the South African dinosaurs that we know of at present!

Willem

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