The Origin of titans makes no sense.

[VikingWarmaster]

It's based on one of the earliest forms of life from the Cambrian Explosion and thought to be the earliest ancestor to worms. Cambrian period life forms were bizarre yet some fossils survived.

Personally I think that the literal hundreds of millions of years it has acted like an intelligent parasite, it only wants to survive and allow it's hosts to survive, hence the titan powers. I'm more interested in what it did before AoT, considering that the events we see are only 2k years and it's the Origin of All Life.

[ShuyinMK]

It was also theorized that when Ymir first transformed she absorbed the tree as well. This is where the size of her Titan came from as well as the titan's "photosynthesis" like quality where they are active in sunlight but low on energy at night. Also their bodies regenerate similarly to how a plant can regrow.

[DimarisPlays]

Armin: How do titans exist?

Zeke: Worm goes wigglin'.

[famat]

The tree seems to be inspired by Yggdrasil, the holy tree in Norse mythology. Everything else exists around Yggdrasil, including the 9 worlds (ringing any bells?). It also has 3 branches, mirroring Ymir's 3 daughters.

Ymir is also a person in Norse myhtology. He is the ancestor of all jötnar, who funnily enough are called the same in japanese as titans (巨人 kyojin). In poems about Ymir, it's mentioned that when ymir lived, there was not sand nor sea, the exact things Armin wanted to see.

Edit: I did some more research after this comment and literally found MORE stuff... I'm truly impressed a single person was capable of writing this story.

[GgStopper]

From fighting titans to learning earth earliest life forms☠️🙏🏿

[k-money]

It is called a Hallucigenia or Primoridal worm which essentially is in reality like one of if not the first form of life to ever exist on the planet but for some reason seemingly looked like it needed a host to reach its full potential which is how Ymir became the founder because she fell into the tree where the hallucigenia had been for who knows how long and so it fuzed with her spine and granted her the primordial power over life which came in the form of titan shifting making her the first titan to ever exist but when she died the worm still stayed part of her and their consciousness remained in the 9

[animelovegirl]

"no backstory"
*Proceeds to break down it's complexity

[pingusoldier]

When the boy and his dog entered the tree
I knew there was going to be just a generation of dog titans if they ever want to unshovel the dirt off this series's coffin

[princeprocrastinate]

The way Zeke describes it is as a primordial force that existed even before the universe that adapted and survived, and that this is what we call life. If the hallucigenia is the manifestation of that, it makes sense that something like the paths could form from the union between it and Ymir. If it came from a place outside of time and space, before the universe as we know it came to be, then it's not far fetched to see how something like the Paths and the power of Titans could be produced by it.

[DirtyDeedsDoneDirtCheapDC]

The fact Eren's tree grew up like Ymir's tree suggests something was still inside Eren's head, the hallucigenia survives for the kid and the dog to obtain a new power

[coulditbebutter]

It's a "god" of sorts. Zeke said that after many years of matter being created and fading away, one piece of matter withstood time, and that's the creature.
It had an official name iirc

[WanderinOni]

Perhaps it’s like the creatures during the Cambrian explosion. Obviously one couldn’t be that big but maybe if the AOT world had a much keep oxygen rich atmosphere that humans have adapted too?

[Collosal_Titan]

If everything will make sense it will no longer be fiction.

[sor]

I'm pretty sure Zeke was just talking about life in general and not the worm. The worm is a mystery.

[Hronika-kwpl]

And the kid at the end enters the same tree repeating the story again

[dcks]

I researched about it 2 years ago bc the curiosity was killing me, I drew a conclusion(if my memory serves right):

I think that tree is supposed to be reminiscent of Yggsadril, which is a huge tree in Norse mythology that is said to be the center of the world. This tree is divided into 3 roots that connect all 9 worlds(or something like that). One of the worlds happens to be Jotunheim, the land of the giants.

My headcanon was that the worm from AOT was some kind of manifestation of that world that leaked out through the tree, and it happened to find Ymir, then Ymir fused with it when it attached to her spine, and thus titans became a part of the human world.

[imjustamemerbro]

What if it's all a loop? Like after some years people will find out about the Tree and start the titan war again then another Eren would appear and do the rumbling again

[ropengou]

Cosmicism works like that, It goes beyond any understanding, and guess It was the purpose. Quite lovecraftian if u ask me

[Guy.]

I wonder if there is bigger reason why wrens founding titan looks like that insect and not just because his head was shot off and reattached

[vitornadai]

NO it kind of have an ok-ish origin. the thing that sucks is that it just disappeared with no explanation during the fight, Reiner grabs it and we never see it again