One angry face gifted with talent can make everybody miserable, that's for sure. Or angry. These emojis are definitely related.
Why are skulls included in this section? It's because the set was created by an anthropologist. The only thing that mattered to him were the remains of ancient people, who tended to die unnaturally at a very young age. That's why Cro-Magnons were highly likely to have sad smiles. Or furious.