thedailywhat:

Damn Nature U Pretty of the Day: Sarosh Jacob goes for a dip in Jellyfish Lake on the island of Eil Malk, Palau.

Twelve thousand years ago these jellyfish became trapped in a natural basin on the island when the ocean receded. With no predators amongst them for thousands of years, they evolved into a new species that lost most of their stinging ability as they no longer had to protect themselves. They are pretty much harmless to humans although some people with very sensitive skin may get a minor irritation from them.

[thanks sarosh!]