When a jellyfish is stretched straight, it is taller than a 10-story building? You read that right, it is a jellyfish

Have you ever seen a jellyfish taller than a ten-story building?

Image credit: Schmidt Ocean Institute

What on earth is this long thing that looks like a snake? Is it a simplified version of the Milky Way in the deep sea?

NO! It is not.

This is a strange animal discovered by scientists from the Schmidt Ocean Institute in the southern waters of Australia - the siphonophore. It is about 45 meters long and is considered the longest animal in the world.

Tube jellyfish, Image source: Schmidt Ocean Institute

If you look closely, you will find that the siphonophore is different. Strictly speaking, it is not an independent life form, but a unique life form formed by a group of zoospores.

Strange tube jellyfish

The zoospores that make up the tube jellyfish originate from the same fertilized egg, which undergoes multiple divisions and becomes numerous zoospores, which eventually form the tube jellyfish. Although each spore has a self-survival structure, they still choose to live in groups.

The different spores that make up the tube jellyfish not only have fixed formations, but are also given different "skills". For example, some spores will become swimming bells, regularly arranged at the top of the tube jellyfish, and push the tube jellyfish in the water by muscle contraction, while some spores are responsible for predation and can catch food with tentacles. However, one type of spore is usually only responsible for performing one task.

Spores of siphonophores Image source: Wikipedia

Giant siphonophores generally live in the deep sea and have long been accustomed to the extremely high pressure in the deep sea. Therefore, once they swim to a place with less pressure, their bodies will rapidly expand until they explode.

The unknown "stunt" jellyfish

In addition to siphonophores, there are many unique members in the jellyfish world.

The peach blossom jellyfish is harder to see than peach blossom luck

Jingzhou is located in the middle and lower reaches of the Yangtze River, where a kind of jellyfish that lives in freshwater lives - the peach blossom jellyfish. In the 37th year of the Wanli reign of the Ming Dynasty, the peach blossom jellyfish first appeared in the "Guizhou Chronicles".

After that, records of peach blossom jellyfish began to appear in many ancient books. Peach blossom jellyfish often appear when peach blossoms are in full bloom. Its shape is similar to peach blossoms and has many colors. However, it only appears for a short time and in random places, so it is not easy to see it once.

Peach Blossom Jellyfish, source: gbif

In 1880, the British made the world's first specimen of the peach jellyfish from a water tank in a park. Since then, more than a dozen species of peach jellyfish have been discovered around the world.

The immortal jellyfish

From ancient times to now, immortality has been an unattainable myth. However, the immortal jellyfish has already mastered the way to eternal life.

Image source: Wikipedia

The Turritopsis dohrnii is a small jellyfish with a bell-shaped body, about 4-5 mm in diameter, and a transparent body. At first glance, you can clearly see the red digestive system. The secret of their immortality comes from a "special skill" - sexually mature individuals can "rejuvenate" and return to the previous development stage (polyp).

Then, when the environment is right, it will regenerate into a sexually mature individual. Theoretically, there is no limit to the number of times this "rejuvenation" process can be repeated, so the Turritopsis dohrnii is close to immortality.

Italian researcher Piraino and his team conducted experiments on 4,000 Turritopsis dohrnii jellyfish at different stages of development, inducing transformation through four experimental conditions: starvation, change in water temperature, reduction in salinity, and mechanical damage.

The results showed that different species of Turritopsis dohrnii jellyfish would experience the phenomenon of "rejuvenation", but the process would also vary depending on the degree of development.

Image source: Wikipedia

The 45-meter-long tube jellyfish, the elusive moon jellyfish, the "immortal" lighthouse jellyfish...the world of jellyfish is truly full of mysteries.

Jellyfish are also very cute when they are young. Click on the video if you don’t believe it:

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Review expert: Li Weiyang, a well-known science blogger.

Tadpole Musical Notation original article, please indicate the source when reprinting

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