The evolution of a distinction between the germ line and the soma almost always accompanied the evolution of eukaryotic multicellularity. Along with this novel division of cellular labor, came the evolution of specialized somatic cell types to form reproductive organs. These cell fate decisions have strong potential impacts on organismal reproduction and therefore fitness and the evolutionary process. This leads us to wonder whether and how the evolution of the genome, its component coding sequences, response to mutation. and gene expression characteristics, may be impacted by the germ line and somatic reproductive tissues.
In this line of inquiry, we analyse various molecular evolutionary characteristics of genes expressed in germ line and soma, including evolutionary rate, codon use, and sex bias.