Eons ago, in the perfectly anthropomorphized world that once existed, cardinals and ducks were united as one. Literal birds of a feather, they would wander the Earth and take to the skies as brothers and allies of the Precambrian age. (Or whenever birds showed up -- what do I look like, a scientist?)
But then came the great rift. As human beings began roaming the Earth, they declared that cardinals play baseball and ducks play ice hockey or feature in films starring Emilio Estevez. The fires raged and these once noble friends waged war in the skies as their voices were silenced by the quacks and chirps of discord.