November 3 is World Jellyfish Day

Take the jelly quiz!

1. Who appeared on Earth first, jellies or dinosaurs?

Jellies have been on Earth for at least a half-billion years, and possibly longer.  That is WAY longer than dinosaurs were on Earth…and the jellies are still here.

2.  Who are jellies related too, fish or coral?

Coral! Jellies are part of a group of animals called cnidarians which include corals and sea anemones. Cnidarians have thousands of stinging cells in their tentacles called nematocysts. These cells launch tiny harpoons when triggered which, can sting prey at lunch time or fight off predators.

3.  True or False: Jellies play no significant role in their ecosystems; they just chill and float around all day.

False! Sea jellies are at the base of many marine ecosystems. They are eaten by sea turtles, multiple fish species, and other predators.

4.  What flavor of sea jelly goes best with peanut butter?

Trick question! Sea jellies hate peanut butter. They eat plankton, small crustaceans, fish eggs, and other things that get zapped by the stinging cells of their tentacles as they drift through the ocean.

Everyone loves a jellyfish slideshow!

Sea nettles

Jellyfish in the Komodo Sea, Indonesia

Jellyfish of Kakaban Lake, Indonesia

Moon jellies

Jellyfish of Kakaban Lake, Indonesia

All images by Rhett A. Butler for Mongabay

Watch this awesome video of a jellyfish recorded in the deep ocean!

From NOAA: This stunningly beautiful jellyfish was seen during Dive 4 on April 24, 2016, while exploring the informally named “Enigma Seamount” at a depth of ~3,700 meters. Video courtesy of the NOAA Office of Ocean Exploration and Research, 2016 Deepwater Exploration of the Marianas. 

For more facts about jellies, visit:

Check out this live jellyfish cam from the Monterey Bay Aquarium:

(Live feeds available 7am – 7pm PST)

Credit: Monterey Bay Aquarium

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