Unexpected elements is all about finding the surprising science angles to

everyday news. That's Unexpected Elements from the BBC World Service.

Find it wherever you get your BBC podcasts.

I've come up to a small flat in a working-class district of Morocco's

biggest city, Casablanca, and I'm sat with a young woman in her pink

velour pajamas with newly-strained black hair in a stylish bob.

She's explaining how she learned the gimbali, a large wooden guitar-like

instrument with thick strings. It's the musical centerpiece of a little-known

Moroccan subculture, that of the Gnewa.

The first note I played was on my father's gimbali.

He used to take two gimbali's, one for him and one for me, and start to play it.

I repeat after him. Then he stopped playing, and I need to replicate every note I heard

on the gimbali with my voice.

Asma el-Hemzerwe's father, a local Gnewa master, had hoped to pass the

revered status onto his son. Traditionally, the right to play always passes from man to man.

But Malimra Shida el-Hemzerwe only had daughters, including a particularly mischievous,

but-talented one, Asma. And so she ended up breaking the mold. Today, she's a rising star

of the Gnewa scene. A long marginalized culture of street musicians and beggars.

In recent years, it's been acquiring a growing following in Morocco and around the world.

Today, here in their very busy living room, there's Asma's mother recovering from a

recent illness on a bed in one corner. Her father, her one-year-old son, napping in the heat,

and her new puppy diamond. There's minty being served alongside homemade cakes,

...