Bettina Schulz Paulsson explains the origin and spread of Europe's megaliths, including Stonehenge.
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Abstract
The proposal that RNA preceded DNA in evolution is more than 15 years old. In light of recent studies on RNA processing (including protein-free reactions), present knowledge about eukaryotic gene structure, and studies comparing ribosomal RNA sequences, we propose a train of events for precellular and early cellular evolution.
Speculations on the early course of evolution
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