HOLY SHIT THIS IS CUTE  
GET THE INSULIN NOW

@redweasel  

 
Naw, mang. They be like this funky marshmallow-peep combo.

If bobdude0 started doing Fluttershy more often, we’d all be dead in an instant.

@zippysqrl  
I guess you could say they’re close together, and I suppose there is a tiny bit of elbow in there. still looks like the pit of the elbow to me. well, as long as you’re aware of it, I guess we’re free to see it differently.
 
I didn’t call it the elbow pit because I thought it was the inside of the elbow joint btw. I’m not that dumb. I just meant the armpit looks closer to the elbow than the shoulder to me. and when people draw horses with their elbows sticking out, it looks really weird.
 
anyway, saved thanks. :3

@bobdude0  
They’re different “pits”, though on some animals they’re close together enough that they might be considered the same pit, even when they’re probably not because of subtle muscles/tendons separating them under the skin.  

@zippysqrl  
@redweasel
 
I actually referenced my own arm raised, so it’s very much a human-esque arm thing going on. I don’t think it’s too much of a sin though, ponies in this show break anatomy literally all the time, that’s part of being a cartoon.
 
Though, horses and other quadrupeds do have a little “elbow pit” due to their elbows being so close to their chests. There’s some loose skin connecting elbow to chest on most dogs I know, veterinary med student here haha
 
I’m probably saying things you’ve both already worked out (I didn’t actually read too closely, my b) but here’s a photo of some “elbow pits” on a poor little pug with a rash so you can see what it’d more likely look like on Sweetie here, minus the rash of course haha

@redweasel  
Oh boy did I word that last message poorly..  
Not directly under the shoulder, no, that’d be silly. I meant it’s because of the range of motion that bone has (combined with the motion of the other one that looks like a shoulder blade) relative to the torso, not the rotation of just the shoulder joint and how the skin & muscles wrap around them, it’s not directly related to the actual shoulder joint.  
(also a “flex” is still a rotation, just mostly/entirely fixed along the axis perpendicular to both bones)
 
Anyway yeah, this argument is silly because canon ponies are semi-anthro, and therefore entirely unrelated to the picture.

@zippysqrl  
rotation? they flex a little bit I guess, but just to be springy. I don’t know I’ve ever seen any rotation. there certainly is not a pit underneath the shoulders.
 
this is the sort of thing I’m talking about. the forearm is up along the ribcage. there is a slight bulge sometimes in front, but the “pit” is most certainly right there at the elbow, where the arm meets the torso.
 
again mlp ponies ignore this rule when they’re hugging, but do conform to that skeleton when they’re walking or gallopping. they’re like transformer-ponies or something.
 

@redweasel  
Their position may be fixed, but their rotation certainly isn’t, it’s because they have rotation that there’s a “pit”.  
(As an artist who has studied horses quite thoroughly, you’d think I know)

@zippysqrl  
I’m pretty sure in horses the shoulders are fixed within the chest cavity for structural support, not even a movable joint. the part that comes out of their body starts at the elbow, and what we call a (front) knee is comparable to a human wrist.
 
and FiM ponies have upper arms sometimes, but you can’t really tell if they do, if they’re not bending their arms.

@redweasel  
The “elbow” may be much closer to the body for horses but it’s still technically the pit of the shoulder, just the skin is connected very close to the elbow.  
Though sweetie here clearly has more human-like forearms so that’s definitely just your typical armpit.

what do you even call those, elbow pits?

Bob’ll be the end of us all one day.

@zippysqrl  
I don’t know how, but the shoulders make her look a little cuter.

@Blissey1  
smh

@HighRollerHydra  
sure you were

@zippysqrl  
You know I was joking, right?

@HighRollerHydra  
Sir, those are hind hooves, they’re in shadow.

@HighRollerHydra  
that’s not her tail

That purple tail under her desk gave me bad thoughts.

This is just horrifically cute.

HNNNNNNNNNNNNNG

@Dirty Bit  
That’s not glue, or milk. it’s hoof lotion

@PoolofCarp
 
Cheerilee: wide-eyed scrunchy face

Ms. Cheerilee? My glue tastes funny.