Table 3.

Estimates of average evolutionary divergence of sequence pairs between and within avipoxvirus subclades and orthopox virus clades^a

Clade	Avg evolutionary divergence (SE)													Distance (SE)
	Avipox											Orthopox
	A1	A2	A3	A4	A5	A6	A7	B1	B2	B3	C	OW	NA	1	2
Avipox A1		(0.016)	(0.016)	(0.024)	(0.021)	(0.019)	(0.016)	(0.043)	(0.046)	(0.048)	(0.050)	(0.097)	(0.102)	0.001 (0.000)	0.000 (0.000)
Avipox A2	0.107		(0.004)	(0.024)	(0.021)	(0.016)	(0.013)	(0.042)	(0.049)	(0.049)	(0.047)	(0.104)	(0.111)	0.016 (0.004)	0.014 (0.003)
Avipox A3	0.098	0.020		(0.024)	(0.020)	(0.014)	(0.013)	(0.042)	(0.050)	(0.048)	(0.046)	(0.105)	(0.110)	0.005 (0.002)	0.006 (0.001)
Avipox A4	0.169	0.165	0.158		(0.027)	(0.022)	(0.024)	(0.044)	(0.043)	(0.051)	(0.054)	(0.099)	(0.104)	0.000 (0.000)	0.000 (0.000)
Avipox A5	0.151	0.142	0.132	0.190		(0.022)	(0.024)	(0.051)	(0.054)	(0.050)	(0.060)	(0.087)	(0.094)	0.000 (0.000)	0.000 (0.003)
Avipox A6	0.120	0.099	0.078	0.149	0.140		(0.016)	(0.039)	(0.049)	(0.044)	(0.052)	(0.088)	(0.089)	0.005 (0.002)	0.003 (0.001)
Avipox A7	0.104	0.086	0.079	0.161	0.171	0.103		(0.038)	(0.052)	(0.051)	(0.043)	(0.105)	(0.110)	0.010 (0.003)	0.007 (0.003)
Avipox B1	0.354	0.356	0.359	0.345	0.386	0.312	0.327		(0.026)	(0.034)	(0.048)	(0.120)	(0.124)	0.017 (0.003)	0.024 (0.003)
Avipox B2	0.391	0.392	0.402	0.335	0.419	0.390	0.436	0.206		(0.033)	(0.054)	(0.115)	(0.131)	0.050 (0.008)	0.036 (0.006)
Avipox B3	0.385	0.401	0.400	0.378	0.391	0.369	0.426	0.262	0.226		(0.059)	(0.114)	(0.116)	n/c	n/c
Avipox C	0.421	0.406	0.401	0.435	0.477	0.423	0.366	0.409	0.45	0.481		(0.107)	(0.119)	0.000 (0.000)	0.000 (0.000)
Orthopox OW	0.778	0.827	0.83	0.775	0.751	0.745	0.819	0.942	0.917	0.907	0.871		(0.019)	0.013 (0.003)	0.016 (0.003)
Orthopox NA	0.804	0.864	0.854	0.823	0.789	0.758	0.849	0.975	0.973	0.882	0.933	0.148		0.076 (0.011)

^aEstimates of average evolutionary divergence of sequence pairs between and within avipoxvirus subclades (A1 to A7, B1 to B3, and C) and orthopoxvirus clades (Old World [OW] and North American [NA]). The number of base substitutions per site from averaging over all sequence pairs between (matrix) and within (columns) groups is shown. Standard error estimates are shown in parentheses. The results of within-group analyses are presented in the last two columns: the within-group analysis for column 1 was performed on a partial DNA polymerase sequence (555 bp) alignment (n = 121), while the within-group analysis for column 2 was conducted on concatenated (981-bp) DNA polymerase and 4b core protein sequences (n = 109). Potential recombinants were excluded from the analysis. Evolutionary analyses were conducted in MEGA5 (39). n/c, not calculated.