Animal Consciousness

I'm teaching a seminar on The Origin of Species this semester with a colleague who is writing on animal consciousness and it's generated a bunch of conversation around these parts, so I figured I'd raise the question here.

At what point do we attribute consciousness to animals? Surely goal directed behavior is not sufficient. Electricity "seeks" the path of least resistance. Heat flows from hot to cold. Metal is attracted to a magnet. Yet, no one will want to grant consciousness to these objects. At the other end, complex mammals like elephants, dogs, and apes clearly have some sense of self and awareness of their surroundings and what they can do to them. Where do we draw the line? Bees complex dances tell other bees where food is. Ant colonies have incredible differential roles for individual members. Fish schools have helpful functions. Where do we draw the line between conscious and non-conscious? Or is there a line to be drawn at all?