I just read the paper and the were some mistake. First , they assume that prokaryotes gave rise to eucaryotes. They also group bacteria and archea into prokaryotes. These two statments goes against the new theory of cell evolution.
Bacteria and Archeae also exhibit group II introns in their genes
Their idea is interresting but the I am doubtfull about some details
They just published in Science.. you'd think that the journal has a very strict peer reviewing policy..
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