<P> This article lists the largest species for various types of organisms, and mostly considers extant species . The organism sizes listed are frequently considered "outsized" and are not in the normal size range for the respective group . </P> <P> If considered singular entities, the largest organisms are clonal colonies which can spread over large areas . Pando, a clonal colony of the quaking aspen tree, is widely considered to be the largest such organism by mass . Even if such colonies are excluded, trees retain their dominance of this listing, with the giant sequoia being the most massive tree . In 2006 a huge clonal colony of Posidonia oceanica was discovered south of the island of Ibiza . At 8 kilometres (5 mi) across, and estimated at around 100,000 years old, it may be one of the largest and oldest clonal colonies on Earth . </P> <P> Among animals, the largest species are all marine mammals, specifically whales . The blue whale is believed to be the largest animal to have ever lived . The largest land animal classification is also dominated by mammals, with the African bush elephant being the most massive of these . </P> <P> The largest single - stem tree by wood volume and mass is the giant sequoia (Sequoiadendron giganteum), native to Sierra Nevada and California; it typically grows to a height of 70--85 m (230--280 ft) and 5--7 m (16--23 ft) in diameter . </P>

Which is the largest living animal on the earth