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 including Mesosaurus 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.
 The location of the
discovery |
 Hendrik & Giel
Steenkamp |
 Gondwana 260Ma ago |
The two continents 95Ma ago |
Mesosaurus tenuidens fossils 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.
Whitehill Formation
|
Bowel section with coprolite
|
Spinal section
|
Lower Jaw and Needle like teeth
|
Rear section, leg & foot |
Mesosaurus tenuidens |
A beautifully 'sandwiched' trace fossil |
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 similar fossils being found in Southern Africa and also in
Brazil added further support to the theory that the continents were once been
joined, and the creature once 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 brasiliensis
whereas those found in Southern Africa are known as Mesosaurus tenuidens
The Fossil 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 2 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 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 fossils 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 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
Mesosaurus Tour pt 2
Of Interest: 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.
Mesosaurus tenuidens
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