Tuesday, March 9, 2010
Evolution in the Test Tube
On page 129, Jerry Coyne describes an experiment performed by Barry Hall and his colleagues at the University of Rochester, in which they removed a gene from E. coli that would have produced an enzyme that would have allowed the bacteria to break down lactose into subunits that could be used for food. After a few chance mutations, the bacteria evolved so that it could still take up lactose despite not having the special enzyme necessary - another enzyme took over the process, and ultimately, a different gene allowed the bacteria to take up lactose in the environment more easily. If we were to repeat this experiment, would we obtain the same results that Hall and his colleagues did? Did these mutations occur simply by chance, or were they somehow influenced by the environment that the bacteria was in? Provide outside research on Hall's experimental design and discuss situations in which we wouldn't get the same results that Hall got after performing this experiment.
Posted by Sara Bahmanyar at 5:38 AM