Figure 1. Increase in network connections and gene essentiality changes between yeast and mouse.

(a) Gene essentiality changes between yeast and mouse. The numbers of essential and nonessential genes of yeast (left) and mouse (right) are presented. (b) A network evolution model describing gene essentiality changes. (c) Network connections of the four phenotypic classes. The first two panels display the average number of network connections in yeast and mouse respectively. Error bars indicate the standard error. The last panel shows the fold increase in the average number of connections in mouse relative to yeast.