Glory to Allah, Who created in pairs all things that the earth produces, as well as their own (human) kind and (other) things of which they have no knowledge. (Yasin:36)
And of His signs is that He created for you from yourselves mates that you may find tranquility in them; And He placed between you affection and mercy. Indeed in that are signs for a people who give thought. (Ar-Rum:21)