'Water bears' is a colloquial name for tiny multicellular critters (typically 0.05-1.5mm long, depending on the species) that have always delighted microscopists. They are properly called tardigrades, and with four pairs of stumpy legs with a slow lumbering gait they do look like a microscopic bear (an eight legged, microscopic bear, that is).
Tardigrades ( Water Bears ) live in moss and ferns. They are some of the most amazing animals on Earth. They can survive:
- Temperatures as low as -200 °C (-328 °F) and as high as 151 °C (304 °F);
- Freezing in a block of ice,
- Lack of oxygen,
- Lack of water for as long as decade(s).
- Levels of X-ray radiation 1000x the lethal human dose,
- Most noxious chemicals,
- Boiling alcohol,
- Low pressure of a vacuum; like that of space,
- And high pressure (up to 6x the pressure of the deepest part of the ocean).
They may be microscopic, but are very cool!
