Hydrothermal vent systems support a unique ecosystem.

To survive in these extreme habitats, vent-associated organisms show a range of morphological and physiological adaptations to cope with challenging environmental conditions, including temperature, metallic sulfides, anoxia, hypercapnia, and extremely lower pH. This shallow-water hydrothermal vent system of Kueishan Island (24°50’N, 121°57’E), off the coast of Taiwan, has been described as one of the most acidic vents on earth, discharging water with a high content of elemental sulfur particles, temperatures of 76-116°C and a minimum pH of 1.5-2.5. In such a harsh environment, hydrothermal vent brachyuran crab, Xenograpsus testudinatus, is the only recorded metazoan species that is endemic to the areas.

To survive in a sulfur-rich circumstance, living creatures may evolve unique and adaptive features toward sulfur resistance. Such unusual tolerance of those possible creatures has long fascinated researchers. The molecular mechanisms enabling exceptional tolerance have remained largely unknown and could serve as available information regarding one planetary habitability and the origin of life during planetary evolution. These acid-base and ions regulation mechanisms of crustaceans are a key for species evolution and crucial for ecological sustainability in the future. Besides, compared to other research groups studying deep-sea hydrothermal vents, the ease of access to a shallow hydrothermal vent field places us in an advantageous position.