Kate has posted a special article by Brian Playfair which looks at the interpretation of Anubis as a jackal and offers an alternative suggestion. Here's a short extract from the introduction:
We all know the image of Anubis, we see it in every tomb but how many of these images are wrongly interpreted ? Listed as Anubis the jackal headed god but are we sure that is correct ?
In many Old and Middle Kingdom tombs at Saqqara and Beni Hassan especially those of Nobles, we see practically the same image in both hunting and domesticated form which cannot be a jackal. These are clearly hounds – canines of a very particular breed type depicted as hunters and companions. This middle-sized hound with prick ears and noble presence was the tjesm. Early settlers in the Nile valley in pre dynastic time showed prick eared canines hunting in their art and as the quality of art developed we see this hound in a clearer form, which is no trained or domesticated jackal.
The tjesm was such an important asset to the ancient Egyptian especially when he became a companion as well as a great hunter that it is inconceivable he was not represented as one of the major deities.