12,000 to 15,000 years ago one of the limestone rock islands in the nation of Palau sealed itself off from the ocean and became a marine lake. A few jellyfish were sealed inside, and with virtually no predators, they began multiplying and evolving. Today more than 10 million jellyfish inhabit Ongeim’l Tketau, known as Jellyfish Lake to tourists.
Their sting became evolutionarily useless, and has been lost over time, to the point that the jellies are completely harmless to swim with. Swimming in Jellyfish lake, surrounded by a translucent sea of rhythmically pulsing creatures, is known to be unbelievably serene. The jellies, varying in size from basketballs to blackberries, slowly undulate as they follow the path of the sun across the surface of the lake.
source: wiki.
pic:NatGeo
that seems equally beautiful and terrifying…even if they are without sting
