“ Yes , wording makes sound unlikely — viruses specialists unusual events , ” riposte David L. Robertson , virologist University Glasgow regards lab escape conspiracy theory. “ Recombination naturally , frequent viruses , recombination breakpoints spike protein codons appear unusual exactly ’ sampled enough. ” Robertson correct evolution always producing results may seem unlikely fact not.Viruses generate untold numbers variants see one-in-a-billion natural selection picks survival.But argument could pushed far.For instance , result gain-of-function experiment could explained one evolution would arrived time.And numbers game played way.For furin cleavage site arise naturally SARS2 , chain events happen , quite unlikely reasons given .