3′-UTR lengths in Arabidopsis and M. truncatula genes. A. The average 3′-UTR length from non-orthologous genes in M. truncatula (Mtr.Not), orthologous genes in M. truncatula (Mtr.Orth), non-orthologous genes in Arabidopsis (Ath.Not), and orthologous genes in Arabidopsis (Ath.Orth). Numbers of genes are: 6388, 8876, 7060, and 8876, respectively. Median values (nt) are: 180, 203, 169, 176, respectively. The Wilcoxon rank sum test outcomes for the hypothesis that 3′-UTR lengths of orthologous and non-orthologous genes are the same are P = 2.655e-31 in M. truncatula and P = 1.926e-08 in Arabidopsis, thereby indicating that the 3′-UTR lengths from orthologous genes are longer than that from non-orthologous genes. B. 3′-UTR lengths in pairs of orthologous genes between M. truncatula and Arabidopsis. Number of orthologous genes is 8876. The Pearson correlation is 0.26 (p-value < 2.2e-16). C. 3′-UTR lengths of 2000 randomly-selected and assembled gene pairs between M. truncatula and Arabidopsis. The Pearson correlation is 0.