"Earthly Aliens" --500-Million-Year-Old SuperPowers of Jellyfish: "Survived all Five of Earth's Extinction Events" (Weekend Feature)

People rarely enjoy meeting a jellyfish. On the beach they appear limp, amorphous, and blistered in the sun. In the water it's often a brush of a tentacle on exposed skin followed by a sting. They hardly evoke the serene...