• Question: Why is some hair curly and some hair straight?

    Asked by Soph45 to Christopher, Dan, Jen, Mohan, Sarah on 13 Mar 2017.
    • Photo: Daniel Fovargue

      Daniel Fovargue answered on 13 Mar 2017:


      As a curly haired scientist I was interested in this question. I didn’t know the answer though, so I had to read up a little bit. I guess there are differences in the hair structures and follicles that can cause curly vs straight hair. But I actually ended up being more interested in why there are two types at all. It turns out (at least a theory is) that original humans were mostly curly haired to better protect the head from sunlight, since they lived near the equator. As humans moved away from the equator, certain groups developed straight hair in order to get more sunlight on their skin. So nowadays both sets of genes are around.

    • Photo: Jen Dennis

      Jen Dennis answered on 13 Mar 2017:


      Erm, the honest answer is that I don’t really know! The best I can do is say it’s got a lot to do with genetics but, beyond that, I’m not sure.

    • Photo: Sarah De Vos

      Sarah De Vos answered on 14 Mar 2017:


      The same reason why we are all different: the answer is in our genes. Some people have the curly hair gene and some have the straight hair gene. I didn’t know why but Dan has explained this above, so I’ve learned something new today! Curly hair tends to have flatter follicles and less smooth cuticles than straight hair. My hairdresser once told me that your hair type can change every so many years. Weirdly my hair has started to become wavy (I’ve always had super straight hair)!

    • Photo: Christopher Mirfin

      Christopher Mirfin answered on 15 Mar 2017:


      Cos curly is the best 🤣 – but yeah it’s genetic (unless you have straighteners)

    • Photo: Mohan K

      Mohan K answered on 15 Mar 2017:


      Its all in the genes!

      In terms of mechanics, hair follicles may be round to produce straight hair, or oval. Oval hair follicles will produce spiral shaped strands… aka curly hair!

Comments