Yes I kind of agree the pointy ears don't really seem to be of much importance.
I kind of thought Ymir (and possibly the Ape) were something different from other shifters. Somehow the talk between RB and Y seems to debunk this idea (well, at least for Ymir).
As of why the shifters' titan form is so different from regular ones', I'm unsure. Maybe mindless titans (the regular ones) kind of evolve into a different form until they manage to get their human-self back, and the deviant type is an intermediate stage between those two 'starting' and 'ending' points?
Also, despite Yimir's titan looks a lot like regular titans in some aspects, I do find it as being definitely different still.
But then you need to start wondering why other Colossal titans which look exactly like Berth's are inside the wall... maybe distinct classes of titans do exist.
As everything else within SnK, all of this is still pretty much mysterious. Need more info.
Ymir is definitely the most deformed looking titan so far.... It does seem like there is something inherent to the whole size thing classification we see with titans. 15m class titans so far seem to be the least deformed to so speak. Well, they are deformed but not to the extremes we see other titans. On the other hand ymir's titan head size seems to be normal among titans her own size. What is she, a 6 meter class? I am pretty sure we have seen a lot of titans her size with heads like that.
Anyways, human titans generally show the following:
- Muscular and lean bodies
-Proportions make sense overall (safe for ymir who has a giant head)
-Faces surprisingly less human than that of other titans.
Overall what I find most interesting is the face part. All titans we generally see have extremely human looking faces. In turn human titans generally look kinda less human in the face area. Eren's face is not human like at all so to speak. Reyner has his face covered with hardened skin. Berholt has his face appear to have no skin whatsoever. Annie looks reaonably human although she does not look the same as other normal titans. She has a different color as far as I can tell and seems more defined so to speak. Ymir has the huge head and looks almost beastlike overall.
Thinking about it, we know for a fact that titans at large are former humans. However most titans don't succesfully transform, only a few seem to do so for whatever reason. Overall the manga has presented the nape of the neck as the weak point of the titans however human titans have shown that is where they are when they transform at large. I am thinking that the nape of the neck is basically a titan's cockpit basically. Thats where they are controlled from. What I am thinking is that normal titans are failed titan transformations. In their case the human's body becomes the titan rather than a titan appearing around them. In the case of succesful titan transformation the body grows around the human in question.
Now, interestingly it seems like some of the personality of normal titans remains with human titans. Ymir wandered for 60 years as a seemingly mindless titan and eren has lost control a couple of times. What if normal titans are led by whatever it is that makes human titans loose control? Basically normal titans are driven by the uncontrolled emotions which initially take over a human titan.
How about another theory.... So far it seems titanism is some sort of ambiguous disease. However the manga is not necessarily clear on whether it is a physical disease or a supernatural disease. Even titan's weird bodies don't necessarily give much clues on that matter considering that at best the supernatural appearance of titan skins over humans seems to be made so as to make titan's bodies make sense in the physical world (being very light for example). Anyways, what if the way titanism spreads is kinda like being possessed by a titan spirit of sorts. Perhaps something that those rec movies.... So you have titans possessing humans and those who reject the possession turn into mindless beast and those who don't reject it turn into human titans. The same logic could apply for your regular zombie infection though. There is a virus, condition or bacteria which induces the transformation. Those who reject it turn into normal titans and those who don't turn into human titans.
And one final crackpot theory. One way or another it does seem like the relationship between humans and titans is actually meant to be symbiotic so to speak. Titans basically put in power and humans put in will, intelligence so to speak. The combination of both is what makes a human titan. Now, what if the titans instinct is not per say to eat humans... but rather they are putting humans within themselves in an attempt to be like human titans? A titan's instinct is not in itself to eat humans but rather they are looking to put a human in control of their bodies. Think about it, the only part of a titan that seems to have any functionality is the nape overall. For normal titans its empty and they attempt to fill it via eating, except it does not work.
What if R&B's actual goal is to free the Titan's inside the walls? Only they have no idea where to locate the Wall Titans to set them free and this is why the church refuses to reveal anything, because they know humanity is not the only intelligent life on the planet.
Well, Reiner did state their original goal was to exterminate people inside the walls. Then they changed their mind because of <put your own theory here>.
P.S. it's been suggested by different people that Annie might have revealed the existance Titan inside the wall on purpose. She had some big respect for Armin, so that might have been her own way to say 'Look Armin, right now you think I'm a murderer, but things don't actually stand as it might seem, look at what people has been hiding from you for all this time'.
---------- Post added at 05:18 PM ---------- Previous post was at 05:16 PM ----------
One thing that bothers me about Grisha is that he just appears on the scene (ch3g20).
We really don't know the origin of Grisha. Whether he was from inside or outside the wall, or what his pedigree is, except that his first mention is arriving when a widespread disease was killing people.
I wondered a bit if Eren is possible not Eren's child, but was "rescued" because of something Ymir said: that Eren doesn't remember either (ch. 47, 17) I thought, I wonder if Eren was a titan that regained humanity, or whatever and was found by Grisha, or regained huamnity because of Grisha. But now, I don't think so. I think Eren is Grisha's son, but there is something weird about Eren because of what Ryner asks Ymir: Do you think Eren's power is more reliable than ours? (46, 44).
Eren's powers are special or different or more reliable, probably because of the serum his dad gave him. Eren has memory problems and apparently has spent time wandering off on his own as a child. Methinks there is more secrets about Eren than we know. Ryner had falsified memories, maybe Eren does as well?
It seems that over chapters 46-47 Ymir knows what's what. but Ryner asks 3 questions: Do you think this world has a future? We both want to do something about Christa? Do you think Eren's powers is more reliable than ours?
Ryner and Bertholdt are looking for the Coordinate. Ymir was with Christa, new the fact that she was hiding her name, and was sticking to Christa for her own benefits.
Yet it seems that Ymir knows a great deal. She knows who the enemy is, but wouldn't tell Eren (what would be the problem with telling him?). She knows quite a bit about R & B, and apparently, she knows enough to realize whether this world has a future or not (probably not), and decides to join R & B's side.
There are just too many question marks without answers so far. But that makes for fun speculating until we get the real answers.
Interesting questions, except all Reiner meant by asking if Ymir thinks Eren is more reliable is whether Eren is a better partner to have for Ymir's purpose: protecting Krista/Historia. Right now, at least until Eren shows some incredible improvement in his ability to fight as a titan, he's probably the weakest of the four.