11 interesting facts about water bears
- Microscopic critters known as tardigrades, or water bears live in droplets of water or freshwater pools.
- The water bear have barrel shaped bodies and clamber around on eight stubby legs.
- It has recently been demonstrated that tardigrades can survive the vacuum of open space and solar radiation combined for at least 10 days.
- Water bears, also called tardigrades, feed on the juices of moss and other plants, and sometimes on other animals.
- Radiation — tardigrades can withstand median lethal doses of 5000 Gy (gamma-rays) and 6200 Gy (heavy ions) in hydrated animals (5 to 10 Gy could be fatal to a human).
- When they lose water, they can go to sleep for up to 100 years. A little water is all it takes for them to spring back to life.
- When a water bear is in this drought resistant state is called a tun.
- Water bears need moisture to stay active but they can curl up and hibernate for up to a century if their habitat dries out.
- Tardigrades can survive being heated for a few minutes to 151 °C (424 K), or being chilled for days at –200 °C (70 K), or for a few minutes at –272 °C. (~1 degree above absolute zero).
- Recent research has revealed that they can also withstand pressure of 6,000 atmospheres, which is nearly six times the pressure of water in the deepest ocean trench.
- Tardigrades can undergo chemobiosis — a cryptobiotic response to high levels of environmental toxins.
