pathways, the evolutionary dynamics of metabolic networks remains poorly
understood. Our work concentrates on the integration of comparative genomics, metabolic network analysis and microbial selection experiments to examine
(i)the contribution of different genetic mechanisms to network growth, (ii)the selective forces driving network evolution, and
(iii) the integration of new nodes into the network. We start by asking whether selection can favour resilience against mutations in metabolic networks. Next, we examine the relative contribution of horizontal gene transfer and gene duplications to network growth, and the possible selective advantages provided by these mechanisms. Last, we ask if physiologically coupled enzyme modules are co-evolving units.