The clitoris is a sexual organ which is only found in female mammals. In humans, the visible button-like part is located near the front junction of the labia minora, before the opening of the urethra and vagina (see above illustration). In contrast to the penis, which is homologous to the clitoris, the clitoris does not include the distal part of the urethra and functions solely on the initiative of sexual pleasure. The only known exception to this is in the Spotted Hyena. In these species, the urogenital system is unique, because the female urinates, mates and gives birth on an extended, erectile clitoris which is also known as a pseudo-penis.