Among living big cats, male lions are characteristically distinguished by a mane. The mane is a growth of longer hair around the head, neck, shoulders, and chest, making the adult male lion immediately recognizable.
A lion’s mane usually begins developing during adolescence as testosterone levels rise and may reach full size at about four years of age. Its color can range from blond or reddish-brown to very dark brown or black. Cooler climates can also be associated with heavier manes, which is one reason zoo lions may look more heavily maned than some wild lions.
Scientists generally regard the mane as a sexual signal. Darker, fuller manes can indicate maturity and condition and may influence female choice or competition between males. The older idea that the mane primarily protects the throat during fights remains debated.
The feature is not perfectly universal: some male lions, particularly in hot regions such as Tsavo in Kenya, have sparse or nearly absent manes. Lionesses almost never grow full manes, although rare maned females have been documented. These exceptions do not change the standard quiz answer.