Table 2. Different (Δ) ages of IGD and HGT per clade.

	With positional information			Without1
	HGT	IGD	Δ 2	Δ 2
Streptococcus	0.10	0.0	+0.10*	+0.09**
Enterobacteriaceae	0.03	0.0	+0.03**	+0.03**
Bradyrhizobiaceae	0.10	0.10	0.00	+0.01**
Bacillus	0.05	0.02	+0.03**	+0.01**
Pseudomonas	0.04	0.01	+0.03*	+0.03**
Helicobacter	0.04	0.04	0.00	+0.02**
Neisseria	0.03	0.02	+0.01*	+0.01**
Sulfolobus	0.04	0.0	+0.04**	+0.02**

1 Analysis using only the sequence threshold to disambiguate between paralogs and xenologs.

2 Mann-Whitney-Wilcoxon test:

*p<0.01,

**<0.001.