Which animal is strongest on earth?

1. These species have lived since Cambrian era(500+ million years ago), twice as old as dinosaurs and they are still living…STILL LIVING…Digest that !!!
2. They can chill, have a cup of coffee and roam wearing shades at temperatures ranging from -200 to 150 degree celsius.
3. They can be found atop the Himalayas as well as the depths of the ocean, Japanese hot springs, several metres under glaciers in the Arctic and even in space. :o :o
4. They can survive upto 6000 times the atmospheric pressure.
5. They can survive 1000 times the lethal human dose of X-ray radiation.