The Gender symbols are derived from the astronomical symbols. The male symbol is derived from the symbol of mars. It is formed by rotating the Venus symbol to 135 Degrees. The cross was changed to an arrow, so that it resembles a shield and spear. On the other hand the symbol for female is derived from the symbol of Venus. It represents a hand mirror and is symbolic for beauty. You can see these images on the link below:
SymbolsOn
SymbolsOn