Standing on your hind legs—which is the behaviour under discussion—is costly to rabbits—since it increases the chance of being observed by predators—so they can’t do it all the time.
Not only that, you can only look in one direction at a time. You do need to know where the fox is. The rabbit only loses a couple of hundred milliseconds if the fox decides to make a dash for it anyway.
Not only that, you can only look in one direction at a time. You do need to know where the fox is. The rabbit only loses a couple of hundred milliseconds if the fox decides to make a dash for it anyway.