who came up with the male and female symbols
Gender symbol The two standard sex symbols are the Mars symbol ♂ (often considered to represent a shield and spear) for male and Venus symbol ♀ (often considered to represent a bronze mirror with a handle) for female, derived from astrological symbols, denoting the classical planets Mars and Venus, respectively. They were first used to denote the effective sex of plants (i.e. sex of individual in a given crossbreed, since most plants are hermaphroditic) by Carl Linnaeus in 1751.[3]
Early Christian art and architecture The dove is a symbol of peace and purity. It can be found with a halo or celestial light. In one of the earliest known Trinitarian images, "the Throne of God as a Trinitarian image" (a marble relief carved c. 400 CE in the collection of the Prussian Cultural Heritage Foundation), the dove represents the Spirit. It is flying above an empty throne representing God, in the throne are a chlamys (cloak) and diadem representing the Son. The Chi-Rho monogram, XP, apparently first used by Constantine I, consists of the first two characters of the name 'Christos' in Greek.