Tardigrades or water bears or moss piglets are eight-legged micro animals. They were first described  in 18th century and were called “little water bears” or Tardigrada – “slow steppers”.

They have been found everywhere in Earth’s biosphere, on mountains, in the deep sea, volcanoes, tropical forests and the Antarctic.

Tardigrades can survive extreme conditions: high and low temperatures,  high and low pressures, air deprivation, radiation, dehydration, and starvation that can kill most other known forms of life. Tardigrades have survived exposure to outer space with high radiation and without air.