this giraffe is not that giraffe

Why did the Messages app on this phone update itself, changing how all the emojis look? I rarely select to update it due to things like this. But maybe I did unwisely select it last time, sigh. And then a few days later it finally applies the changes.

Now I see (what I suspected before but did not know for sure) that the emojis I send aren't necessarily what the other person receives.

Dang, I sent a picture of a giraffe from the side, showing its long neck. Now my phone shows it as only a picture of a giraffe's head, head-on. Totally NOT equivalent! ::SMH::

Update, later that day:
I didn't change anything, but now the emojis are back to how they were before. Weird.