Penis
Domestic cats have barbed penises, with about 120–150 one millimeter long backwards-pointing spines. Upon withdrawal of the penis, the spines rake the walls of the female's vagina, which is a trigger for ovulation. Lions also have barbed penises. Male felids urinate backwards by curving the tip of the glans penis backward. When male cheetahs urine-mark their territories, they stand one meter away from a tree or rock surface with the tail raised, pointing the penis either horizontally backward or 60° upward.
Western quoll
The western quoll is about the size of a domestic cat. It is coloured a rufous brown and has 40–70 white spots on its back with a creamy white underside. Its spots actually help diminish its outline from the moon at night when hunting. It has five toes on its hind feet and granular pads. The head and body are about 36 cm to 46 cm in length, and the tail is around 22 cm to 30 cm. With large eyes and pointed ears, it is well adapted for nocturnal life. The black brush on its tail extends from halfway down to the tip. Males typically weigh around 1.3 kg, and females 0.9 kg. The longest they are likely to live is four years.