Table 1. Estimated evolutionary time (t).

	t (MYA)
Onset of diversification of the subfmaily Bathumodiolinae	21.1±3.6
Split of Groups 2 and 3	19.4±3.4
Split of Groups 1-1 and 1-2	14.1±3.0
Split of B. brooksi and the other members in Group2	13.3±1.7
Split of East Pacific subcluster from the common ancestor of Indo-West Pacfic and Atlantic subclusters in Group 2	(12∼10)a
Onset of diversification in Bathymodiolus spp. of Group 1-1	11.2±2.5
Onset of diversification in Gigantidas spp. of Group 1-2	10.4±2.5
Split of B. hirtus from the common ancestor of Sissano B. spp. 1 and 2, Kikaijima B. sp., and Chamorro B. sp. in Group 1-1	9.8±2.3
Split between Indo-West Pacfic and Atlantic subclusters in Group 2	9.7±1.0
Split of B. aduloides and B. manusensis in Group 3	8.4±2.6
Split of B. japonicus from the common ancestor of B. securiformis, B. tangaroa, and Sissano B. sp. 3 in Group 1-1	6.6±1.8
Onset of diversification of Atlantic species in Group 2	6.2±1.2
Split of B. platifrons from the common ancestor of B. mauritanicus and B. childressi in Group 1-1	3.8±1.2
Split of B. securiformis from the common ancestor of B. tangaroa and Sissano B. sp. 3 in Group 1-1	3.5±1.5
Split of B. thermophilus and East Pacific sp. in Group 2	2.6±0.9
Onset of diversification in Cluster A of Group 2	0.9±0.4

^areference time.