Here is a thread made specifically to show images that a participant has questions regarding if they are compliant to the rules.
I think so, though I'm not the qualified judge on that I can see depth in it as you've shaded the penguin to have a light source in front of it. So I'm pretty sure it's not allowed.
The front area looks like it has been 'burnt', which is a form of shading. I have no issues of using a darker color, like black, to differentiate between different body parts. 'Using 'dodge' is also not advised. It too is a form of shading.
