Darwinisme en die bakterieë

The course of development of the theory of evolution at the turn of the century hardly influenced early bacteriology, and reasons for the lack of a reliable phylogenetic classification of bacteria at the time are presented. Causes for adoption of the doctrine of the inheritance of acquired characteristics in bacteria, in an effort to explain the wonderful adaptability of bacterial populations, are examined. This doctrine prevailed until at least the mid-forties. Experimental results then started appearing which indicated that adaptive mutants arose as a result of random mutations which were only subsequently selected at phenotypic level. Die ontwikkelingsgang van die evolusieleer tydens die eeuwisseling het die vroeë bakteriologie skaars geraak; die redes vir die destydse gebrek aan 'n betroubare filogenetiese indeling van bakteriee word in hierdie artikel aangebied. Oorsake vir aanvaarding van die leer van die oorerflikheid van verworwe eienskappe, om sodoende die wonderlike aanwendbaarheid van bevolkings bakterieë te verklaar, word ondersoek. Die geloofwaardigheid van hierdie stelling het tot minstens die middel-veertigerjare behoue gebly. Eksperimentele waarnemings het toe daarop begin dui dat aangepaste mutante alleenlik as gevolg van lukraak mutasies verskyn wat eers later op die fenotipiese vlak gekeur word