In this photo provided by Schmidt Ocean Institute, a rock crust sample, upside down, reveals Oasisia and Riftia tubeworms, as well as other organisms. (Schmidt Ocean Institute via AP)
In this photo provided by Schmidt Ocean Institute, experiments code-named "Mesh Box Staining Gadgets" are sealed to the seafloor at the Tica Vent, a site on the East Pacific Rise 2,500 meters deep. (Schmidt Ocean Institute via AP)
In this photo provided by Schmidt Ocean Institute, an eelpout swims by a tower of tubeworms at the Tica Vent, a site on the East Pacific Rise 2,500 meters deep. (Schmidt Ocean Institute via AP)