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‘Rise of the Continents’

11 Jun

In the new BBC series ‘Rise of the Continents‘ Professor Iain Stewart discussed the origin of the African continent in the first episode, which aired on the 9th June and is available on the BBC Iplayer here, and nicely tied the opening episode with evolutionary history.  Africa is rich in wildlife and geographical diversity, and it is, of course, the birthplace of our species, Homo sapiens.  For me this program highlighted the importance of understanding geology and geography when considering the origin and evolution of animal life on earth (us included, of course).  In particular the way in which the continents themselves effect evolution through the combined changes of the landscape, climate and geography, which are fundamentally altered through deep geological time as continents shift.  This is important in considering the effects of both evolution on animal species (including the Homo lineage), and the impact of a changing landscape on human populations.

On viewing the program (and becoming engrossed by the palaeontology), my immediate thoughts shifted to two massive geographical changes which impacted on European human and animal populations during the Mesolithic period.

Doggerland‘ is the modern name for the submerged landscape where now the North Sea sits in North-West Europe.  However, up until around 5000 BC the area was dry land which helped connect the islands of the UK to mainland Europe, and the area, termed ‘Doggerland‘, was home to a variety of flora and faunal populations and home to hunter-gatherer humans societies (Gaffney et al. 2009).  This was due to water being locked up in the form of ice during the last Ice Age which substantially lowered sea levels in the North Sea basin.  However, from the Last Glacial Maximum (23,000 to roughly 13,000 BC) to the Late Glacial Maximum (11,000-8,000 BC) in the Northern Hemisphere, the environment changed and the sea level rose, eventually separating the modern day countries of the UK and Ireland from mainland Europe.

On the other side of Europe another monumental landscape change was underway.  The Black Sea, located in South Western Europe, has long been a focus of on-going palaeoclimate research (Siddall et al. 2004, Turney & Brown 2007; also see the UNESCO funded project ‘Caspian-Black Sea-Mediterranean Corridor during the last 30 ky: Sea Level Change and Human Adaptive Strategies‘).  In particular it was unclear whether the Black Sea, with its highly fluctuating water levels, remained an isolate lake during the Late Glacial Maximum, or whether it remained connected to the world sea by the Bhosporus and Dardanelles straits.  Studies and modelling (Siddall et al. 2004) suggest that the Black Sea water level was a lot lower during the Late Glacial Maximum, but following this period increased in water level and overall size.

It’s important to reflect on the effect that these landscape changes would have had on prehistoric cultures.  ‘Doggerland’ is well known for the amount of artefacts and animal bones that are dragged up by trawlers and other fishing vessels (Gaffney et al.  2009), whilst archaeologists have found prehistoric structures and artefacts in the flooded landscape of the Black Sea.  In particular it marked a time of isolation for the islands of Britain and Ireland, which are reflected in the material culture following the separation.  The Black Sea infilling proper likely caused human populations around the area to adapt and change their strategies in hunting and surviving.  With the advent of agricultural in Europe during the Neolithic period (roughly 7000BC-1700BC), the trade and exchange of ideas, material cultural and people was no doubt influenced by changes in the landscape.

The ‘Rise of the Continents’ series is well worth a watch, and I am particularly looking forward to future episodes in the series.

Bibliography:

Gaffney, V., Fitch, S. & Smith, D. 2009. Europe’s Lost Land: The Rediscovery of Doggerland. Council Of British Archaeology: York.

Siddall, M., Pratt, L. J., Helfrich, K. R. & Giosan, L. 2004. Testing the Physical Oceanographic Implications of the Suggested Sudden Black Sea Infill 8400 Years Ago. Palaeoceanography. 19: 1-11.

Turney, C. S. M. & Brown, H. 2007. Catastrophic Early Holocene Sea Level Rise, Human Migration, and the Neolithic Transition in Europe. Quaternary Science Reviews.  26 (17-18): 2036-2041.