Complex sentence: Female Hawaiian Ducks have a strange attraction to male Mallards (a more general species of ducks in the same area), it's unknown whether the female Hawaiian Duck attracts the male Mallard or whether the color variation of the male Mallard attracts the female.
Split into simpler sentences: Female Hawaiian Ducks have a strange attraction to male Mallards (a more general species of ducks in the same area). It's unknown whether the female Hawaiian Duck attracts the male Mallard or whether the color variation of the male Mallard attracts the female.