eDNA is an excellent method that is simpler and more environmentally friendly at a lower cost compared with conventional methods. The marine biological data obtained have been far less than the physical and chemical data. A great deal of effort and time had been required to get information on macroorganisms, even at a single point in the vast ocean, using conventional methods. On the other hand, eDNA analysis provides spatiotemporally dense information on macroorganisms. In the future, by accumulating big data on living organisms using eDNA corresponding to physical and chemical data in the sea, we can get useful ecological characteristics of macroorganisms that we could not see before. We expect to obtain new knowledge not only about the correspondence between organisms and the environment but also about the interspecies interactions.
