Males and females have organs to get the sperm and the egg to unite. In case of mammals, males have a specialized organ penis (separate from the anal tract) to deliver sperms to the female; and females have a specialized organ separate from both the anal and urinary tracts to receive sperms from the male. In case of birds, reptiles and fish, mostly chloaca are used, which is a common egress for sprems, eggs, feces and urine; though in exceptional cases like water-fowl, males possess a separate phallus and females may have a separate subchannel in their chloaca to receive the phallus.