Hey shortwavers, we want to wish you a happy Black History Month.

And this month, as we do all year, we are celebrating and amplifying Black Voices in STEM.

Scientists, engineers, folks in medicine and math, and this week, we're bringing you

new guests with expertise and insights to share, and returning to some of our favorite conversations.

Tina Lassici is one of the few biological anthropologists in the world who studies the

evolution of hair.

And we wanted to give you the chance to meet this history-making hair scientist again.

Enjoy.

Tina Lassici has some news for you.

That stuff growing on your head is technically fur.

Humans like to pretend that they're special, and in some ways we are, okay?

But having a whole different word for our fur, that's just vanity.

That's right.

Our hair is technically fur on our heads, just keratinized fiber growing from scalp follicles.

But for your vanity and for mine, we're going to call it scalp hair.

And Tina is one of the few biological anthropologists in the world who studies it.

I'm a postdoctoral researcher at Penn State University who works on human evolution and

specifically the evolution of human scalp hair.

Tina first got curious about the evolution of human scalp hair in college.

She was in her first biological anthropology class, and her teacher pulled out this world

map, showing the distribution of UV radiation, so where UV rays hit the most, closest to

the equator.

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