In a phenomenon that has left scientists in awe, giant marine cephalopods have been reaching unprecedented proportions. The lion’s mane jellyfish, a species found in the cold waters of the Atlantic Ocean, Pacific Ocean, and the North Sea, is one such example.
The lion’s mane jellyfish is the largest known jellyfish on Earth, with an impressive bell diameter of 7 to 8 feet and a thick ‘mane’ of trailing tentacles that can reach up to 60 feet in length. This giant jellyfish has been observed in the cold waters of the Atlantic Ocean, Pacific Ocean, and the North Sea.
The lion's mane jellyfish (Cyanea capillata) 'is' a species of jellyfish that inhabits the world's oceans.
It is known for its distinctive appearance, with a bell up to 3 feet in diameter and tentacles reaching up to 120 feet long.
This massive jellyfish can weigh up to 200 pounds and has been found in cold and temperate waters.
Its sting is painful but not usually life-threatening to humans.
Lion's mane jellies are biologically important, serving as a food source for many marine animals.
The lion’s mane jellyfish is equipped with stinging cells called nematocysts, which release neurotoxins into its prey to immobilize it. The jellyfish uses its frilled arms to scoop up tiny crustaceans, small fish, and smaller jellyfish, which become trapped in its sticky tentacles. Despite its stinging skills, the lion’s mane jellyfish has predators such as sea turtles and sea anemones that can eat it.
The sting of the lion’s mane jellyfish is a danger to some, but a boon to others. Tiny sea creatures like juvenile whiting and walleye pollack find safe haven amidst its tentacles, while their predators steer clear of the lion’s mane.
Lion’s mane jellyfish can be found swimming in the Northern Hemisphere, with increasing sightings in places like Cape Cod and Nantucket, Massachusetts, the Gulf of Maine, and off the coast of Ireland. Climate change is making life harder for many marine animals, but most jellyfish, including the lion’s mane, are thriving as waters warm.
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Climate change refers to significant long-term changes in the Earth's climate, primarily caused by human activities that release greenhouse gases, such as carbon dioxide and methane.
According to NASA, the average global temperature has risen about 1°C since the late 1800s.
The main causes of climate change include burning fossil fuels, deforestation, and industrial agriculture.
Rising sea levels, melting glaciers, and extreme weather events are some of the consequences of climate change.
If you get stung by a lion’s mane jellyfish, don’t pee on the affected area to neutralize the venom. Urine can make the sting more painful and might even prompt attached barbs to unleash more toxins into your body. The best remedy is to douse the spot with vinegar to remove any tentacles, then apply a heat pack.
Like other jellyfish, the lion’s mane has no brain or heart, but it manages just fine without one. It can eat, swim great distances, reproduce, and retreat in defense, thanks to a complex nerve network running throughout its body. Jellyfish also have no bones, just a free-flowing, shape-shifting bell and body made of 95 percent water.
As impressive as the lion’s mane jellyfish may be, it doesn’t stick around for long, living only about a year. The lion’s mane jellyfish reproduces both sexually and asexually, with males releasing sperm through their mouth and females catching them to fertilize eggs within pouches on their oral arms.
Lion’s mane jellyfish are bioluminescent, producing their own light in the darkness of the deep sea. They emit a magical glow as they glide through the water, making them an enchanting sight for those who encounter them.
Bioluminescence is a natural phenomenon where living organisms emit light.
This process occurs in over 75% of ocean species, including plankton, fish, and squid.
Bioluminescent creatures use this ability to communicate, attract prey, or defend against predators.
The chemical reaction that produces bioluminescence involves a molecule called luciferin reacting with oxygen to produce light.
This process is often used in scientific research, particularly in the study of marine ecosystems.