Fig. 5
From: Bone-associated gene evolution and the origin of flight in birds
Functional annotation of positively-selected genes in birds and mammals. The heat map on the left represents the percentage of positively-selected genes in birds and mammals for each GO category. Terms directly associated with bones are highlighted in bold, and those where there is a significant statistical difference between birds and mammals, upon Fisher’s Exact Test, are marked with two asterisks (**). The heat map on the right presents the ratio obtained in heat map on the left for each GO term, divided by the ratio of positively-selected genes in birds and mammals respectively. A value great than one is indicative that there is evidence that the GO category has experienced positive selection