In some cultures, semen is attributed with special properties of masculinity. Several tribes of Papua New Guinea, including the Sambia and the Etoro, believe that semen provides sexual maturation among the younger men of their tribe. To them, sperm possesses the manly nature of the tribal elders, and in order to pass down their authority and powers, younger men of their next generation must fellate their elders and ingest their semen. This custom commences among prepubescent males and postpubescents.[47][48] This act may also be attributed to the culturally active homosexuality throughout these and other tribes.[49]