Tardigrades (also known as water bears or moss piglets) are water dwelling, microscopic animals, with eight legs. Tardigrades are in the phylum tardigra which means slow walker. Tardigrades occur over the entire world from the high Himalayas (above 6,000 meters [20,000 feet]) to the bottom of the ocean (below 4,000 meters [13,000 feet] and from polar regions to the equator and even in space! Tardigrades are the only animal that are able to live in space for up to 10 days. Though tardigrades can live all over the world, the best place to find them is on moss or lichens. other places to find them is in sand or water which they can fit 25,000 tardigrades on per liter (litre). A Tardigrade's max length is up to 1.5 millimeters but they can be as small as 0.1 millimeters.