Why were the gods with animal heads?

This is due to the fact that this animal could be a symbol of this deity. For example, the god Anubis had the head of a jackal, and the god Ra had the head of a falcon. In addition, the ancient peoples believed that the gods are beings of a higher order. Thus, they had to be somewhat different from ordinary mortals. One of these differences was appearance, as well as physical data. So the gods were very often beautiful, especially when it comes to goddesses.