Tuesday, 5 May 2015

Ancient links between climate and vegetation... by Jonathan Dean

Skyline of Minneapolis
Dr Jonathan Dean is part of a new multi-million pound project that hopes to shed new light on the possible links between environmental change and the emergence of our species...

I'm a Post Doctoral Research Assistant based in the Stable Isotope Facility at BGS Keyworth.  In April, myself and 14 other scientists from the UK, Germany and Ethiopia flew out to Minneapolis. We were there to begin our study of half a kilometre of sediment cores that were taken from an ancient lake on the Ethiopian-Kenyan border last year. Our multi-million pound project, funded by NERC, ICDP and German and American funding bodies, aims to help us to understand how climate and vegetation has changed over the past 500,000 years, and is part of a wider project that involved the drilling of 5 lakes across the region. The UK team is led by Prof. Henry Lamb from Aberystwyth University.

Our home for a week, 6 stories underground, at the University of Minnesota in Minneapolis
So far, such long-term reconstructions of environmental change from east Africa have been lacking, which means we do not yet understand how the environment changed through the time when our species, and our ancestor species, evolved in the region. Scientists have speculated that environmental changes could have played a role in the timing of our evolution and subsequent dispersal from east Africa, but only when our studies are complete will we be able to test this thoroughly for the first time.

The cores were then split in half lengthways, so we could see the patterns of sediments inside, and so we could take samples for analysis back in our home labs.
The sediment cores are being stored at the world-leading LacCore facility at the University of Minneapolis, where we were able to split open, photograph and scan with instruments to investigate changes in the elements present. We also took samples at intervals along the core; I will analyse mine at Keyworth for oxygen and carbon isotopes, to reconstruct changes in the amount of rainfall over time. Other people took samples to date the cores and to investigate changes in vegetation through time.

Scanning the cores.
So, watch this space over the next few years as we publish our results and shed new light on the possible links between environmental change and the emergence of our species…

Jonathan
Follow me on Twitter @jrdean_uk

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