The image is an example of an illuminated manuscript. The concept was to
combine religious text (Christian and Islamic) and artistic detail, in
order to emphasize the importance of the text. At one time, illuminated
manuscripts were the only legalized, accepted form of art.
Most likely a wolf would lie down belly up to
show submission
This is a friendly amd submissive gesture because when its doing this its trying to look smaller
It'll also roll over to show a dominant wolf that
it is helpless and not aggressive