The most successful animal species, in terms of biomass, may well be Antarctic krill, "Euphausia superba", with a fresh biomass approaching 500 million tonnes, although domestic cattle may also reach these immense figures. However, as a group, the small aquatic crustaceans called copepods may form the largest animal biomass on earth. A 2009 paper in "Science" estimates, for the first time, the total world fish biomass as somewhere between 0.8 and 2.0 billion tonnes. It has been estimated that about 1% of the global biomass is due to phytoplankton, and 25% is due to fungi.