Continent world ultimately persisted with these being regarded as separate continents. From the late 18th century, some geographers started to regard North America and South America as two parts of the world, making five parts in total. Overall though, the fourfold division prevailed well into the 19th century. Europeans discovered Australia in 1606, but for some time it was taken as part of Asia. By the late 18th century, some geographers considered it a continent in its own right, making it the sixth (or fifth for those still taking America as a single continent). In 1813, Samuel Butler wrote of Australia
Smallest organisms mass and drinks eight times its total body mass each day. Its nest is 3 cm across. The vulnerable Kitti's hog-nosed bat ("Craseonycteris thonglongyai"), also known as the bumblebee bat, from Thailand and Myanmar is the smallest mammal, at in length and in weight. The Etruscan shrew ("Suncus etruscus"), is the smallest mammal by mass, weighing only about on average. The bumblebee bat has a smaller skull size. The smallest mammal that ever lived, the shrew-like "Batodonoides vanhouteni", weighed only . The smallest member of the rodent order is the Baluchistan pygmy jerboa, with an average body length of only