Artefacts after rendering Hey guys im back with another artefactproblem, it seems like this forum loves this topic (0 replys to my last question regaring artefacts)

But to the end of this year i hope that a good soul helps me. 
So lets start

Like you can see below, the rendering creates areas on my skin which are colored darker than the rest. My mesh is not the best, but i could be much worse so i cant figure out what causes these problem. Below you can see the rendered image. The mesh in viewport and leave you my .blend file.

So i hope you can help a new user like me .)

Best regards, Marc!

[.blend file is compressed and hair is removed]
The head is using Material.006 for the skin except for those areas coloured dark.
The dark areas (faces) have material.021 assigned to them!


Just a note to add:
Your mesh is using flat shading on all the faces (this is probably why you are needing 61.000+ vertices just for one ear).

I would suggest you set all faces to smooth shading: in Edit mode select all then open the Faces menu with Ctrl F and choose the Shade Smooth option.