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2 Posts tagged with the origins_evolution_and_futures tag
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Polymerization in hydrothermal conditions: Darwin's prescient idea.

Dave Deamer, Department of Bimolecular Engineering, University of California, Santa Cruz CA

 

In an often quoted note to Joseph Hooker in 1871, Darwin speculated that life may have begun in a "warm little pond." We have tested this idea in simulations of fluctuating hydrothermal fields associated with volcanism. We found that the chemical energy available in such conditions can drive polymerization of ordinary mononucleotides into surprisingly long oligonucleotides resembling ribonucleic acid (RNA). The polymerization occurs in lipid environments so that the RNA-like polymers become encapsulated in membranous compartments to form protocells, the first milestone on the evolutionary path toward primitive cellular life. 


Energy and Matter at the Origin of Life

Nick Lane, Department of Genetics, Evolution and Environment, UCL

 

There is a paradox at the base of life. Membrane bioenergetics - the use of ion gradients across membranes to drive carbon and energy metabolism - are universal, but membranes are not. Radical differences between bacteria and archaea in membrane chemistry and active ion pumping suggest that LUCA, the last universal common ancestor, may have used natural proton gradients in alkaline hydrothermal vents to drive growth. I will outline a possible scenario for the origin of life in this environment, and present some experimental and modelling results which suggest that proton gradients could have driven the transition from geochemistry to biochemistry, and the deep divergence of archaea and bacteria.

Location:

Flett Lecture Theatre, Natural History Museum, Cromwell Road, London - Map

Poster:

Download a copy of the poster here - Poster

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Palaeo-ecosystems in Pleistocene Europe: Insights from stable isotopes of large mammal fossils

 

Prof. Hervé Bocherens, University of Tübingen, Germany

 

Tuesday 3rd February - 4.00 pm

 

Earth Sciences Seminar Room (Basement, WEB 05, the previous Mineralogy Seminar Room)

 

The climatic fluctuations of the Pleistocene have caused dramatic changes in the ecosystems of Europe during the last million years. These ecosystems, cold or warm, included a high diversity of megafauna, in contrast to recent ecosystems under similar climatic conditions.

 

NaturalHistoryMuseum_PictureLibrary_024715_preview.jpgTooth of a woolly mammoth (Mammuthus primigenius)

 

To gain a better understanding of the functioning of these ecosystems with no modern analogue, the isotopic composition in carbon, nitrogen and oxygen of the large mammal fossil bones and teeth were used to document key aspects of their ecology, such as habitat, diet preference, niche partitioning, and predator-prey interactions. In addition, isotopic analysis of fossil hominids and their prey allows the reconstruction of subsistence patterns and inferences on the possible anthropogenic impact on the environment.

 

More information on attending seminars at http://www.nhm.ac.uk/research-curation/news-events/seminars/