Sea Water

Swim With Jellyfish

"Jellyfish Lake is a well-known dive site in the Pacific island of Palau. It is one of the rock islands, a series of small, rocky, uninhabited archipelagos off the coast of Koror. Jellyfish Lake is completely isolated, but in the distant past, it had an outlet to the ocean.

The outlet was closed off and the high jellyfish population was isolated and started to feed on quickly-reproducing algae. Contrary to popular belief, the jellyfish of Jellyfish Lake do have small stinging cells, or nematocysts.

However, because the stinging cells are so tiny, their sting is not detectable on most human tissue, so tourists can enjoy swimming with them much closer than would be possible anywhere else..."

Stingrays

They have no bones, their colour can vary from grey to bright red, be plain or patterned. Adult rays can be no bigger than a human palm or have an overall length of fourteen feet, and a group of them is called a 'fever' of stingrays.

More photos here.

The Immortal Jellyfish

"Turritopsis nutricula is a hydrozoan (jellyfish) with a life cycle in which it reverts back to the polyp stage after becoming sexually mature. It is the only known case of a metazoan (animal) capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary stage (Piraino et al. 1996, p. 302). It does this through the cell development process of transdifferentiation. Theoretically, this cycle can repeat indefinitely, rendering it effectively immortal."