claim: natural selection in the evolution of sars-cov-2 in cattle, not humans, created a highly capable human pathogen
evidence_1: in contrast, our analysis detects significant positive episodic diversifying selection acting on the bat virus lineage sars-cov-2 emerged from, accompanied by an adaptive depletion in cpg composition presumed to be linked to the action of antiviral mechanisms in ancestral hosts.", "the closest bat virus to sars-cov-2, rmyn02 (sharing an ancestor 1976), is a recombinant with a structure that includes differential cpg content in spike; clear evidence of coinfection and evolution in bats without involvement of other species.", 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  "collectively our results demonstrate the progenitor of sars- cov-2 was capable of near immediate human-human transmission as a consequence of its adaptive evolutionary history in bats, not humans.")