To those who claim that traditional marriage is an artificial construct that is not linked to our nature, it is good to recall the following observation of Prof. J. Budziszewski:
“In the case of all other biological functions, only one body is required to do the job. A person can digest food by himself, using no other gullet but his own; he can see by himself, using no other eyes but his own; he can walk by himself, using no other legs but his own; and so with each of the other functions and their corresponding organs. Each of us can perform every vital function by himself, except one. The single exception is procreation. What this demonstrates is that among human beings the male and female powers are radically incomplete and designed for each other.
(Taken from J. Budziszewski, What We Can’t Not Know: A Guide, Ignatius Press, San Francisco, 2011, p. 96.)