As a reward for having angelic voices, hundreds of young boys were castrated to prevent their larynx from fully developing during puberty. This put them at the enviably unique position of having the vocal range of a young girl/boy, while having the strength and lung-capacity of an adult as they grew older; providing them with an incredible amount of vocal flexibility.
These were the castrati, the luckiest talents of the lands.
Now, you know.
This has been a public service announcement. We hope that your horrified squeal and subsequent wetting of your pants didn’t cause you too much embarrassment.