Mesosaurus tenuidens
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Mesosaurus tenuidens
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The Mesosaurus Fossil site is on Farm
Spitzkoppe West 138 which is about 48km north-east of Keetmanshoop alongside the
C17 Road that runs to Koes. Also on the C37 road you will find the Giants'
Playground and the Quiver Tree Forest.
The Spitzkoppe Farm a variety of fascinating features that promise you a
couple of very interesting hours, some unusual sights and excellent photography
opportunities. Here you can visit a hillside where some of the
world's best examples Mesosaurus tenuidens fossils are to be
found. During your guided tour you will be taken to a forest of Quiver-Trees and
see outcrops of unusual dolerite rock formations ' Giant's Playground ' style
and, for those interested in the history of battles, the graves of two young Schutztruppe killed in the 1904-1907 native uprising.
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Mesosaurus tenuidens in Namibia - A discovery that supported and
important theory:
The farms in the south of Namibia
are vast and for most of the year dry. Apart from the scattered tough flocks of African Damara and Dorper
sheep they are seemingly empty. There's always plenty of work to do
on a farm, and every farmer's son enjoys spending his school
vacation time working alongside his father. There are many and
diverse jobs that a farmer has to know and do, so the sooner a boy
takes interest the better he will learn. It was on such a working
day in 1988 when Giel Steenkamp was maintaining one of his farm
roads with his motor-grader that his 10 year old son, Hendrik, shouted for his
father to stop. Hendrik noticed something unusual as the grader cut
its way through the soft laminated sedimentary rock. The boy's keen eyes had
spotted an unusual pattern on one of the rock's faces. A skeletal
pattern. A closer inspection revealed the imprint of a lizard-like
creature's spine along with rib cage, legs and feet. But let us
start at the beginning of this adventure for it involves far more than just the discovery of an
ancient life form.
The Permian Period ( 280 - 248 million years ago)
is known as being the age of the amphibians. It was a time when many
of the land reptiles returned to the lakes and seas in favour of an
aquatic life and the first known of reptile to do so was the
Mesosaurus
(meaning 'Middle Lizard' in Greek). It grew to about 50cm in length
and had a long broad paddle-like tail, which along with its large
webbed feet allowed it to swim
and manoeuvre quickly. Its nostrils were positioned near to its eyes
and forward of the head protruded a long narrow set of jaws equipped
with needle like teeth. There are differing theories with regards to the
eating habits of Mesosaurus. As to whether the needle-like teeth
were used to trap and either chew or filter the small marine life foods
that it preyed upon.
During the
Permian Period this area experienced,
at times, violent dust storms. It is possible that some of the dust
storms were of such intensity that areas experiencing heavy dust
deposits rendered the sea water so muddy that some of the marine
life forms would have 'drowned'. Wind born sands and dusts would
also settle down to the sea-bed covering in a blanket of mud any life forms that
had recently died and not succumbed to scavengers.
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| The location of the
discovery |
Hendrik & Giel
Steenkamp |
Gondwana 260Ma ago |
Gondwana 95Ma ago |
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Mesosaurus tenuidens and the connection with
Continental Drift:
It was as
early as 1620 that the English philosopher Francis Bacon commented
on the apparent similarity of the shape of the West coastline of
Africa and the Eastern coastline of South America. However, Bacon
made no reference
that the two continents could have once been joined. In 1858, an
American called Antonio Schneider made the suggestion that the
continents had somehow moved in respect to each other. But, it
was not until 1915 that German meteorologist Alfred Lothar Wegener
(1880-1930)published in his book, 'THE ORIGIN OF CONTINENTS AND
OCEANS' the theory of
Continental Drift
. Wegener proposed that the
earth had once consisted of a single land mass surrounded by a vast
ocean. He named this super continent Pangaea and explained that it
had long ago divided forming two great continents - Laurasia in the
North and Gondwana in the South and that, in time, these two
continents had further divided.
Wegener's theory was viewed
with scepticism by the Geological fraternity until the 1960s by
which time advanced scientific measuring equipment had been
developed and the phenomenon of Paleomagnetism was accepted.
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Whitehill Formation |
Bowel section with coprolite |
Spinal section |
Lower Jaw and Needle like teeth |
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Rear section, leg & foot |
Mesosaurus tenuidens |
A beautifully 'sandwiched' trace fossil |
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Mesosaurus tenuidens of Namibia and the Brazilian Connection:
The above left shows the great inland
Lake Gai-As
that lay across an area of the super continent of Gondwana that
would divide about 120 million years ago forming the continents of
Africa and South America. It was along the shoreline of this ancient
lake where Mesosaurus lived.
The discovery of Mesosaurus fossils being found in
Southern Africa and also in Brazil added further support to the
theory that the continents were once been joined, and that
Mesosaurus had inhabited the great inland Lake Gai-As that had in the Permian Period spread deep inland on both of the
modern day continents. The fossil remains of the creature found in
Brazil are referred to as Mesosaurus brazilosaurus
whereas those found in Southern Africa are known as Mesosaurus tenuidens
The Mesosaurus tenuidens Fossils Site on Farm Spitzkoppe:
When looking over the arid landscape of
Southern Namibia it takes an amount of imagination to understand
that this was once the bed of a great inland sea. There are
hills of about 50 metres in height that on closer inspection have
been built by layer upon layer of sediments that were deposited by
wind blown sands and dusts at an estimated rate of 1 cm per 1000
years. The softer areas of sediments that once were positioned
alongside these hills has long ago been washed and 'blown' away. The
sedimentary rocks in this area are known as the Whitehill Formation
which is a carbon rich black mudstone that weathers to a whitish
colour as can be seen above left. Close inspection of the rock
layers, in places, show what appears to be a small hole. Further
investigation usually reveals that this is a point where a
spinal section of a Mesosaurus can be found.
Footnote: The Farm Spitzkoppe West in the Karas Region of Namibia is possibly one of the world's richest and
easily accessible depositories of Mesosaurus fossils. In the future
event of the site being professionally explored one is left to wonder
as to what size of Mesosaurus fossil or even a previously
unknown of ancient life form could be found.
There's a small reception office at the farm where you
will be warmly greeted by the
owner Giel Steenkamp and his son Hendrik, one of whom will guide you on a personal tour of the points of interest on the
farm. Your time is about 2 hours and includes a personally guided
tour of the Mesosaurus site, plus a visit to the farm's own 'Forest
of Quiver Trees and 'Giant's Playground" style Dolerite rock
formations.
Acknowledgements and
further reading: G1, G2, G3, P1, W1, W2, W9
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Mesosaurus Tour pt 2
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Local Area Attractions and Articles of
Associated Interest
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Did You Know ?
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- Pangaea means "All The Land" in Greek.
- The continents of Africa and South America are estimated to
still be drifting apart at the rate of about 1cm per year.
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