#thanks for the original ramble though op!! you're a legend :>

[the-jellydex]

HELLO FELLOW JELLYFISH FAN I SAW A RAMBLE and I am physically incapable of not butting in so please don't mind me.

YES YES YES, you're so right. Jellyfish don't have a brain but do um. things. thanks to a neat little thing called a "nerve net" (in box jellyfish, they actually have a more sophisticated nervous system lovingly called a "Rhopaliar Nerve Network (RNS)"). Technically the same thing as "all nervous system" (though there seems to be different "classes" of nerve nets serve different purposes, there's a fascinating article here by Takeo Katsuo and Ralph J. Greenspan if you want to learn more)

Are you talking about planula?? I love planula! We really need more planula love here, haha. Their exact shape can (naturally) vary by species, but really they can attach onto anything as long as its sturdy enough. Some deep-sea jellyfish lack a polyp stage but those who do often attach onto hard-shell organisms (The Pandea conica or Paper Lantern Jellyfish, however, attaches onto Sea Angels- how cool is that? Here's a picture of her:

I'm SO glad someone mentioned how energy efficient jellyfish propulsion is (like, it's literally the most efficient in the animal kingdom!)- and box jellyfish in particular are known for being the fastest jellyfish (the Chironex fleckeri can swim up to 5 knots :>. I don't know what that is in miles or km tho). It's thanks to a little flap they have on the underside of their bell- I forgot what it was called though. If you ever find a box jellyfish washed up on the beach, you can hear it "whistle" as air flies through that flap

Tbh I don't actually know what causes spawning but I was going to chalk it up to temperature, haha. Did you know that you can induce polyps to strobilate, though? It's usually by temperature and good conditions, but certain groups of jellyfish (Discomedusae and Cubomedusae) can be induced with indole compounds as well. But uh, strobilation is a little misleading for cubozoa because they actually metamorphize from a polyp straight to a baby cubomedusa (some, like the Morbakka virulenta are an exception, and exhibit monodisc strobilation :>. Heehoo). This is rly interesting though, I might have to look up jellyfish breeding season (god, is this like, the equivalent of jellyfish porn or something? /j /this hurt to write)

I can't remember where I read it (it was probably a japanese translated book or article), but it had one of the best explanations of polyps that I've read. It basically went something like "If we compare cherry blossoms to polyps, cherry blossoms produce fruit like polyps produce jellyfish, but the polyps and trees will still continue to make fruit/jellyfish throughout the year.

Box jellyfish can be "aged" by examining their statoliths (gypsum stones that are located under the rhopalia). A new layer is added every day, so biologists use them to determine age (the average lifespan of a box jellyfish is about 3 months, if I remember correctly). Other jellyfish live around a few months to up to two years in captivity though :>

Did you know the person (Shin Kubota) who sustains the longest colony of T. dohrnii's would go onto tv shows and sing songs about the jellyfish at the end? It's not really jellyfish related and it's information available on the Wikipedia but it's really wholesome. I think we need more people like that in the (jellyfish) scientific community

Hello fellow jelly lover!! Autism be encouraged, I would love nothing more than to hear your hyper-fixation rant on jellyfish!! Kicking my feet and twirling my landline cord B*)

Hi hello did you know that jellyfish have no brain? They are simply all nervous system and move around by electrical propulsion. Literally just vibing, no thoughts head empty.

The study of jellyfish is called medusology because jellyfish are actually only a stage in their life! They start out as larva with essentially a dot of glue on their heads and lil tentacle feet (called cilia) which they use to feed with (their mouth and their anus are the same thing lmao). They float around until they find a good solid surface to glue their head to and become a polyp (related to sea anemone and coral)! While a polyp, they feed with their feet and generally just chill for years.

Polyps produce asexually, where they strobilate (aka split apart like mitosis), and sexually, which is where jellyfish comes in!! The polyp splits apart into medusa (jellyfish) which is essentially the polyp’s gonads/sexual reproductive organs! Jellyfish are just floating uteruses/testicles!!!

No one is sure how long they stay in the medusa stage, but most jellyfish are either male or female and will spawn aka release eggs/sperm pretty regularly if they’re eating enough. Jellyfish eat passively as they swim, which is arguably the most energy-efficient swimming method in animals ever. Spawning is controlled by light (?!!) and they all spawn at the same time of day (again, no brains!! Only vibes).

The polyp who produced asexually (created the medusas) can live for many years, producing medusas each year. Jellyfish? Can live for an unknown amount of time. One species, Turritopsis dohrnii, is essentially immortal because it can transform from the medusa stage into a polyp again, essentially never dying.

Anyways. Jellyfish are so fucking cool!! Nature is crazy! I love the ocean and all it’s alien life!!!