Rabbit facial expressions

One challenge we face with Overgrowth, and with the Overgrowth webcomic, is mapping human emotions onto animal faces. Today I decided to experiment with that in my little sketchbook. Even though I'm not an artist like Aubrey, I mentioned in a previous blog post that it's always useful for game designers to practice drawing! I was still not very confident with rabbit anatomy, so I decided to do some studies: I found some reference pictures of rabbit skulls, sketched them, and then tried to reconstruct the full heads from the skulls.

After that, I chose a few different expressions by drawing stick figure faces, and then tried to figure out how a rabbit could make the same expression. Fortunately, it is really easy to find reference pictures for rabbits on the internet, so I could just combine aspects from a few different pictures to approximate each expression.

Some expressions are very difficult to make with rabbits -- they don't really have eyebrows or lips, and their eyes are on the sides of their heads instead of the front. However, we can make up for these limitations by changing the angle of the head. In fact, in Lugaru, all of the facial expressions were approximated by tilting heads to different angles.

Do you have any other ideas on how we can make human facial expressions on animal characters, or any examples of it being done right?