Enemy sacrifices: In the Aztec Empire, a boy began his military training at 17. He could only be considered a man once he captured an enemy and brought him back as his prisoner to be sacrificed.

Bullet ant glove: The Satere-Mawe tribe live deep in the Brazilian Amazon. To become men, boys have to wear gloves made with bullet ants in them. The ants have their stingers facing inwards and have one of the most painful bites in the insect world. The boys cant flinch for 10 minutes.

Xhosa circumcision: The Xhosa people of South Africa need to be circumcised before being considered men. The boys are shaved and taken into the mountains. They live in isolation while a surgeon comes to circumcise them, they cannot return home until they have healed completely.

Hamar cow jumping: The men of the Hamar tribe in Ethiopa must perform this rite before they are allowed to marry. First, the boy is whipped while family and friends look on. Then, he must run across the backs of four castrated cows. Then he can be wed.

Matis hunting trials: Boys of the Matis tribe in Brazil must go on a hunt afer they have had poison dumped in their eyes to improve their vision. Then, they are beaten and whipped. Finally, they must inject poison from the Giant Leaf Frog using wooden needles, which is incredibly painful.

Algonquin Indian trip: Young Algonquin Indian men are taken to a secluded area, caged, and fed a powerful drug called wysoccan. The purpose of this is to make the man forget his memories of childhood. If he remembers, he is given another dose of the drug.

Female infibulation: This is practiced in parts of Africa, the Middle East, and Asia. Female circumcision is a gruesome and sometimes life-threatening procedure. The labia and clitoris are removed. Then, after a wall of flesh forms across the vagina, a small hole is opened for menstruation and urine.

Iria ceremony: The Okrika tribe of Nigeria believe that the young women of the tribe form romantic relationships with water spirits during their childhood. That's why the young girls perform this ritual, to sever the ties with the spirits. They sing by the river for days until a man from their tribe rescues them.

Naghol: This rite is similar to bungee jumping, but its done using vines and the goal is to come as close to death as possible. The men of the Vanuatu people hope to jump and then brush their heads against the ground and survive.

Masai lion hunt: The Maasai people of Tanzania and Kenya replace their warriors every 6-10 years. The next generation of warriors are circumcised and moved into a camp. Traditionally, the men had to kill a lion to complete this rite, but recently the government has stepped in to protect the animals.

Mandan Okipa ceremony: For a Mandan boy to become a warrior, he must fast for 4 days without sleeping. Then, wooden skewers are forced through his chest and he is hung from the ceiling, smiling, until he passes out. After that, his little finger will be cut off as an offering.

Mardudjara circumcision: When young Mardudjara aborigines enter manhood, they are taken to a secluded place. An elder sits on their chest and another will slice their foreskin. Then, he must swallow it without chewing. Then, there is more genital disfigurement welcome to manhood.

Matausa cleansing: The Matausa tribe cleanse their boys of impurity and help them gain the vitality a warrior needs by sticking two wooden canes down their throats until they vomit. Then, reeds are forced up their nostrils and their tongues are stabbed until their blood has been sufficiently purified.

Pederasty: In ancient Greece, this practice is basically a publicly sanctioned relationship between an older man and a young boy. Its believed that it coincided with the beginning of the young boys military career.

The Ogiek roar: After being circumcised, the young boys and girls of the Okiek tribe in Kenya are secluded from the adults. Then, they paint themselves using clay, are haunted by a mythical beast and they become adults when they can replicate the roar themselves.

Sambian purification: When boys are 7, they are taken from their mothers and placed in an all-male hut. For 10 years, they engage in nose bleeding, forced vomiting and defecation and semen ingestion in order to rid themselves of impurities and to become men.

Scarification: This is done throughout the world, but the Sepik River tribes in Papua New Guinea use it as part of an initiation ceremony that lasts weeks and includes public humiliation. Elders use razor blades to cut the young men all over their bodies in a pattern that closely imitates the rough skin of an alligator, in hopes that the alligator will consume their youth.

The Krypteia: Young Spartans would participate in this yearly war against the slaves. Boys as young as 12 would take part in this violent test.

Sweet Sixteen: This rite of passage is used in Western, modernized civilization. It can be embarrassing, but not brutal or violent. Parents usually spend far too much to celebrate their daughters 16th birthday.

Mentawai teeth sharpening: Mentawai Islands natives value beauty, because if a persons soul becomes dissatisfied with the appearance of its body, they believe the person will die. Young females therefore sharpen their teeth to be more beautiful.

Festa de Mocas Nuevas: The Ticuna people of the Northwest Amazon use this initiation to welcome girls into womanhood for all of the girls in the tribe. Beginning at menstruation they are secluded in a small chamber for several months. Its believed they go into the underworld and will return a woman.

Vision quest: Many Native American tribes send their young men off into the wild for several days during a period of intense fasting so that they can find direction in their life.

Aborigine walkabout: Aboriginal tribes of Australia send their young men into the wilderness for 6 months to test whether they are ready to become men. The boys must survive, unassisted. After those months, when they return to the tribe, they become men.

Fula whip match: Young Fula boys must trade whip blows with another boy from a different tribe in order to become a man. The boys must not show signs of fear and the crowd decide who is bravest, and the man.