Fig. 2

Comparison of (a) mutation bias ΔM and (b) selection bias Δη parameters for endogenous and exogenous genes. Estimates are relative to the mean for each codon family. Black dots indicate ΔM or Δη parameters with the same sign for the endogenous and exogenous genes, red dots indicate parameters with different signs. Black line indicates type II regression line [24]. Dashed lines mark quadrants