Do you love singing every time you take shower? Or how about chatting with your lovable friends? Or humming along with a great song while you're doing some work? Well, let's thank our voice to that! As we all know, voice is produced when air rushes from your lungs and makes your vocal cords vibrate whenever you speak. It is important tool in our daily lives because it helps us to understand and communicate with others. And also it can be used to show our talents in singing, debates, theater acting and even in presenting a great poem.
Naturally all of us was born with a small larynx and a thin vocal cords, that's why we have small or high pitched voice as a child. As puberty hits, not only physical characteristics (wider shoulders, longer bones, and stronger muscles) developed but there are also changes inside the body (like increase of hormone secretion). When a boy undergoes puberty, his testicles become larger that causes testosterone level to increase. It is the hormone that causes change in the larynx(voice box), the reason why there's change in the voice. The higher the testosterone level, the larger the larynx becomes. The vocal cords also lengthen and thicken in response to testosterone produced, the longer the cords the deeper and lowered the pitch of the voice. As for girls, when they go through puberty their vocal cords lengthen too but in more modest way making their voice change unnoticeable.
Males have higher testosterone level than female, making their voice deeper than the high pitched voice of females. Testosterone deficiency may cause a boy to not to go through puberty, hence their voice stay smaller than a boy who gone through puberty. In fact, during 16th to 18th century in Italy, they castrated young boys who have talent in singing operatic or religious music so that their voice will remain the same.