A tardigrade measures 1.5 mm long. Your thumb nails measure 1.5 cm long. How many tardigrades can lie down and form a line along your thumb nail? Without water, a human can survive about 100 hours while a tardigrade can survive decades. How many hours are there in 1 decade? If a tardigrade stretches 1.5 mm long but curls up into a ball in the tun state. What's the diameter of the ball? A tardigrade has eight legs, while a human has only two. If X tardigrades and Y humans have together 26 legs, what X and Y could be?