Shura's grandmother starts explaining evolution. If animals couldn't tell that daemons were part of people, they could not act correctly afraid of them - which they must do. Daemons don't have to eat for themselves, and if they help their people hunt, they may attack animals that their current shapes would not disturb. Children's daemons are even more versatile; if the ducks were fooled by Kalavar, Helen could hide, Kalavar could go among them, and then she could turn into a fox right on top of a real duck and there would be dinner.