Gregory et al. performed a global survey of the ecological diversity of viruses in the oceans. They identified 195,728 viral populations, greatly exceeding the 15,280 identified in a previous ocean survey. These viral communities sorted into five distinct ecological zones — the Arctic, Antarctic, bathypelagic, temperate and tropical epipelagic, and mesopelagic. The researchers found that at the per-sample level, the patterns and drivers of viral microdiversity and macrodiversity differed and that microdiversity increased with geographic range. Although the latitudinal diversity gradient paradigm suggests that diversity of species is highest at mid-latitudes and decreases poleward, Gregory et al. found that the Arctic in fact showed high levels of marine viral diversity.