symbolism, n.Trivia

The heart symbol was first used to denote love in the 1250. Prior to that, it represented foliage.

The heart-shaped seeds of the Silphium plant is the reason that we associate hearts with romance. It was a food, a medicine, and one of the first effective birth control. It's believed the Romans drove it to extinction.

The male/female symbols are the alchemical symbols for Iron and Copper respectively, and originally they referred to the Greek gods of Mars and Venus