Jellyfish

Good morning, Imgur! I'm back with another post about something I really love-- Jellyfish!

Jellyfish are gorgeous creatures found all over the world. Yesterday, I mentioned the jellyfish being zooplankton, meaning they are incapable of swimming against currents. They are also believed to be somewhere between 500 and 700 million years old, making them the oldest known multi-organ animals.

Jellyfish have only two layers of skin to protect their internal organs. They have what I like to call an "all-purpose hole" that serves to intake nutrients and excrete waste. Jellyfish come in countless colours and patterns, so here are some of my favourites!

(This is a stock photo that I couldn't immediately find a source for, apologies.)

Jellyfish generally have three phases in their lifespan: larvae, the polyp phase, and the medusa phase. I really love these photos of little jelly polyps!

(Photo by Konstantin Khalturin)

The largest known jellyfish is the Lion's Mane jellyfish (Cyanea capillata), found in mostly high latitude, colder waters. They commonly grow to be around 2 metres (6.5 feet) in diameter and can easily reach 30 metres (100 feet) in length! The largest Lion's Mane on record had a diameter of 2.3 m (7 ft 6 in) and tentacles 37.0 m (121.4 ft) long. They can also have up to 1200 tentacles! (Just look at all those lil stingers!)

When you search Lion's Mane jellyfish, you will often encounter a photo of a gigantic jellyfish being photographed by a diver, who appears to be much smaller than the jelly. Unfortunately, this is a doctored image. This photo, however, is by Alexander Semenov.

Photo by Alexander Semenov.

Fun fact time! This is a Portuguese Man o' War (Physalia physalis) and known to be one of the deadliest jellyfish in the ocean.... Except that it isn't actually a jellyfish! It is a siphonophore and actually consists of a colony of symbiotic organisms that act together as though one animal. The Man o' War has a body that commonly only grows to be 9 to 30 cm (with only about half of that extending above the water), but the tentacles commonly reach around 10 m (33 ft) but some have been found to extend over 30 metres (100 feet)!

(Photo by Steven Frink)

The box jellyfish (Cubozoa class), though, IS possibly the most venomous creature in the ocean. They're shaped rather squarish and can grow to be around 3 m (10 ft) in length. Unlike other jellyfish, box jellies have 24 developed, true eyes. Look at him glow!

This is one of the smallest jellies known to man. It is a species of box jellyfish known as Irukandji and only reaches one cubic centimetre. Don't be fooled at how small they are! Though they be little, they be fierce! These teenies are still known to be highly venomous and can send a victim into cardiac arrest if the sting is not treated immediately.

(Photo courtesy of GondwanaGirl)

Turritopsis dohrnii is a biological phenomena in that it is technically an immortal species (and so aptly named the Immortal jellyfish). These jellies are one of the only species known to revert back to their polyp phase AFTER they have already reached sexual maturity. If the jelly experiences stress, becomes ill, or too old, it can revert to the earlier phase and form a new colony of undifferentiated cells that ultimately can become new cells within the animal.

Aside from disease or predation, these jellyfish are theoretically capable of living forever.

(Unfortunately, I do not have a true source for this image, apologies!)

Even though

White spotted jellyfish have really pretty clustered oral arms that give them a really cool bouncy look!

Chrysaora quinquecirrha are possibly the most commonly imagined species when people mention jellyfish. Sea nettles are widely distributed in tropical waters and put on some incredible displays with their tentacles!

Moon jellyfish (Aurelia aurita) are completely translucent and are often coloured in photos in order to see them. They are another very widely spread species.

Many species of jellyfish only live to be about a year old.

(courtesy of LiveFish Australia)

One last photo by Lucy Trippet. Can you see why I love these? They are so beautiful and have such fascinating history and functions.

Please let me know if you would like to see more posts like this!! Feel free to message me with ideas or suggestions for what you would like to see or how these can be improved. I'm rather new to Imgur and I am still learning. Thank you for reading and I hope you liked the jellies!