Bongo drums
Bongo drums date back to nineteenth century Cuba, and before that to Africa. They consist of a pair of drums joined at the hip, if a drum can be said to have a hip.
As in humans or animals, the relative sizes of the "sexes" differ. The female drum or hembra is larger and the male or macho is smaller.
To maintain a good sound, the hembra tuned to a lower pitch than the macho. Leather drum heads need to be maintained; when they get dry, a small amount of lanolin or almond oil can be rubbed in. Nowadays some drums have synthetic heads, but purists still consider that while animal skin heads require more careful maintenance, they make better sounds.
To hear a virtuoso play bongos, go here.