Anrogenic alopecia (also known as androgenetic alopecia or alopecia androgenetica) is a common form of hair loss in both male and female humans, chimpanzees, and orangutans. In male humans in particular, this condition is also commonly known as male-pattern baldness. Hair is lost in a well-defined pattern, beginning above both temples. Over time, the hairline recedes to form a characteristic "M" shape. Hair also thins at the crown of the head, often progressing to partial or complete baldness.