Table 2. Number of functional OR genes belonging to each clade.

Clade	Bootstrap valuea	Platypus	Opossum	Cow	Dog	Mouse	Rat	Macaque	Human
Class Ib	98.9	31 (11.7)	221 (18.6)	142 (14.6)	160 (19.7)	113 (10.9)	134 (11.1)	36 (11.7)	58 (15.0)
Class II
A	99.0	35	127	111	114	145	154	45	53
B	96.3	10	19	56	39	40	55	19	33
C	95.5	11	34	50	17	48	43	20	15
D	88.4	3	30	25	26	14	15	9	13
E	94.8	12	41	40	37	49	69	6	13
F	94.9	1	37	20	23	11	17	12	11
G	99.8	1	41	46	24	76	89	10	10
H	94.4	0	24	71	47	42	63	4	11
I	99.4	0	11	14	15	19	31	8	10
J	93.3	0	23	21	13	18	20	9	10
K	100	0	8	12	10	9	7	5	9
L	99.3	52	63	2	2	20	25	6	7
M	98.1	0	17	12	8	24	16	3	3
N	99.3	2	15	8	8	15	9	3	6
O	99.4	4	20	8	11	13	9	1	6
P	99.4	0	7	5	8	7	8	5	5
Q	82.2	0	0	15	2	3	3	2	5
R	99.1	0	47	15	11	29	20	3	5
S	100	1	21	18	14	12	12	4	5
AA	97.7	17	18	9	3	27	26	2	1
AB	100	0	2	8	3	19	24	2	2
AC	99.8	1	23	4	3	17	22	2	1
AD	99.0	3	59	4	6	16	16	0	1
AE	99.5	0	2	12	0	15	18	1	3
AF	100	0	4	8	4	13	17	1	1
AG	98.8	1	5	9	4	13	12	3	0
AH	95.7	5	15	7	10	10	10	4	3
AI	90.3	1	12	4	7	8	7	2	3
AJ	100	0	18	6	8	7	9	1	2
AT	97.2	0	3	11	14	5	5	2	1
BA	100	0	0	15	13	4	7	0	0
BB	100	1	5	11	0	2	5	3	2
BC	99.8	0	1	2	0	1	20	2	1
BD	99.1	1	12	0	2	1	0	0	0
Un	–	72	203	169	145	170	210	74	78
Total	–	265	1,188	970	811	1,035	1,207	309	387

Bold characters show the five largest clades for each species. Un, unclassified.

^aThis value was calculated by taking the average among the bootstrap values in 28 phylogenetic trees constructed using the functional OR genes from all possible combinations of two species out of eight species (see Materials and Methods).

^bThe percentage of Class I genes is shown in parentheses.