A new study by Dalhousie researchers used an innovative analytical technique to provide a new estimate of the total number of species on Earth. The estimate of 8.7 million species (plus or minus 1.3 million species) is the most precise calculation of this number to date. The paper, published in PLoS Biology, reveals that 6.5 million species are found on land and 2.2 million live in the oceans. And incredibly, the study predicts that 86% of all species on land and 91% of all species in the oceans have yet to be discovered and described.