Abstract:
 Seafloor hydrothermal activities and associated biological phenomena are one of the most important discoveries in the past 30 years, which breathe a new insight into researches of geology, geochemistry and biology. According to the study about early environments and their evolution on Earth and oldest records of microfossils, scientists realized that seafloor hydrothermal vents possess all factors, such as substances, energy and environments necessary for the origin of life. Under hydrothermal condition, not only some organic substances are synthesized through abiotic ways, but also steep physical and chemical gradients occurring in the interface between vents and seawater provide energy to those hyperthermophilic chemolithoautotrophic microbes. These chemolithoautotrophic microbes act as primary producers in hydrothermal ecosystems, and are the species closest to last common ancestor of life on Earth. A systematic introduction is given to the scientific hypothesis of “Life originates from seafloor hydrothermal activity”.

Key words: Seafloor hydrothermal systems, hydrothermal vents, extremophiles, origin of life