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Andy Farr



physical: Building 16.x // The Station Crescent // Oteha Rohe
tel: +64 9 4140800 ext xxxxx // email: andydfarr(at)


Following a bachelors of Biomedical science specialising in genetics, I commenced a honours year in the Rainey lab under the guidance of Dominik Refardt. The work looked at an area of evolutionary parasitology - the study of why parasities make their hosts sick: the focus of my work was the gut colonizing bacterium E. coli and the bacteriophage lambda which parasitizes it. Lambda is a particularly interesting parasite because not only can it transmit both vertically (as part of the host chromosome) and horizontally (by lysing its own host cell and spreading to naive hosts), but its genetics and molecular biology are well understood. Many infectious diseases such as HIV or Herpes, have this mixed mode of transmission.

Through my experiments I explored the effect of changes in host density on the evolution of virulence. Interestingly, I showed that the capacity to have alternative transmission modes can have a fitness cost for a parasite evolving at high host density.


I'm now trying to work out what to do with the rest of my life: horizontal or vertical -- that is the question.

Andy Farr