| Jellyfish Lake |
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The jelly fish came to this lake in Palau through a tunnel which connected the sea and the lake a long time ago (the tunnel has since been closed). These particular jellyfish have no poison or stingers and live in an environment where there's no predator. Jellyfish Facts Jellyfish are marine invertebrates. Their bodies are composed of a bell-shaped, jelly producing substance enclosing its internal structure, from which the creature's tentacles are suspended. Each tentacle is covered with stinging cells (cnidocytes) that can sting or kill other animals: most jellyfish use them to secure prey or as a defense mechanism. Others, such as Rhizostomae, do not have tentacles at all. To compensate for its lack of basic sensory organs and a brain, the jellyfish exploits its nervous system and rhopalia to perceive stimuli, such as light or odor, and orchestrate expedient responses. In its adult form, it is composed of 94–98% water and can be found in every ocean in the world. Most jellyfish are passive drifters that feed on small fish and zooplankton that become caught in their tentacles. Jellyfish have an incomplete digestive system, meaning that the same orifice is used for both food intake and waste expulsion. They are made up of a layer of epidermis, gastrodermis, and a thick layer called mesoglea that produces most of the jelly and separates the epidermis from the gastrodermis. Since jellyfish do not biologically qualify as actual "fish", the term
"jellyfish" is considered a misnomer by some, who instead employ the
names "jellies" or "sea jellies". The name "jellyfish" is also often
used to denote either Hydrozoa or the box jellyfish, Cubozoa. The class
name Scyphozoa comes from the Greek word skyphos, denoting a kind of
drinking cup and alluding to the cup shape of the animal. |
