shows stochastic colonization of chemosynthetic habitats at least from the mid Triassic
Geiger, D. L. & C. E. Thacker. 2006. Cahiers de Biologie Marine 46: 343-346.
A molecular phylogeny of 40 basal gastropod species representing 14 families (including eight species in four families from chemosynthetic habitats) was constructed, based on 3038 characters (Histone 3, COI, 18S). Unambiguous fossils indicated minimum ages of four major lineages. It suggests that chemosynthetic habitats were colonized several
times independently and date back to at least the mid Triassic.
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