default account picture on iMac

My boss got two new iMacs, and noticed a strange (somewhat disturbing) picture set as her account picture. She only noticed it when she started using the Mail application. Can someone tell me if the iMac has a default account picture, or if there is something weird here?

The account picture on all macs is chosen by the user when they boot up for the first time, you can either choose to set a picture from the default library or take a photo with the isight camera.

It would be helpful to explain a little more about this picture.