Jellyfish are simple, successful and, occasionally, deadly creatures. The Australian box jellyfish has enough toxin in each of its tentacles to kill…Read More »
60 people. Some jellyfish create spectacular blooms when fields of polyps, their stationary life stage, simultaneously bud off into free-floating medusae. These blooms are blamed for the deaths of swimmers, clogged fishing nets and power plant intakes, and in certain parts of the world, like Japan, they appear to be on the rise.
But these problems are associated with only a subset of the creatures we call "jellyfish" – a catch all term for an amazingly diverse group of organisms. It includes corals, true jellies and others with stinging cells, as well as the stingless comb jellies, which swim using tiny hairs, called cilia.
What they also are is beautiful, as the following images attest.
Credit: NOAA/Monterey Bay Aquarium Research Institute
This giant red-hued jellyfish called Tiburonia granrojo was described by American and Japanese researchers in 2003. It grows up to 3.3 feet (1 meter) in…Read More »
diameter and lives at depths of 2,000 to 4,800 feet (650 to 1,500 meters) in the ocean. First seen during submarine dives in 1993, the jellyfish is distinct in that it uses four to seven fleshy arms to capture food, rather than fine tentacles like other jellyfish. Less «
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Credit: Anders Garm
Tropical-dwelling box jellyfish have a cube-shaped body, and four different types of special-purpose eyes: The most primitive set detects only…Read More »
light levels, but another is more sophisticated and can detect the color and size of objects. The Australian box jellyfish is also deadly; each of its up to 60 tentacles carries enough toxin to kill 60 people.
The Australian spotted jellyfish, Phyllorhiza punctata, have invaded the Gulf of Mexico. With plenty of food, they grow as big as dinner plates and weigh…Read More »
up to 25 pounds (11 kilograms), although in their native waters they tend to be much smaller. They are not dangerous to humans, but pose a threat to shrimping and fishing industries. Less «
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Oldest Known Jellyfish Fossils
Credit: Fossil photo by B. Lieberman. Cunina photo by K. Raskoff, copyright.
Fossil evidence of jellyfish dates back to the Cambrian Period, 500 million years ago. This fossil jellyfish shows similarity to the modern jellyfish,…Read More »
Cunina (right). It was one of four different types of jellyfish dated back to the Cambrian by researchers in 2007. These ancient jellyfish showed the same complexity as modern jellyfish, meaning they either developed rapidly 500 million years ago, or today’s varieties are much older. Less «
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Credit: Shin-ichi Uye
The saucer-like Aurelia aurita, or moon jellyfish is carnivorous and feeds on small plankton organisms, such as mollusks, crustaceans and even ctenophores.…Read More »
It can be anywhere from two to 15.7 inches (five to 40 centimeters) in diameter and is found in mostly warm and tropical waters. Less «
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Jellies from Above
Credit: Shin-ichi Uye
The moon jellyfish is common in many parts of the world, and it appears to have increased dramatically in Japanese waters in recent decades. Seen from…Read More »
a bird's eye view, a bloom of moon jellyfish appears as white swaths in a Japanese bay. In Japanese waters, its blooms have interfered with fishermen and power plants.