The texture of hair (curly versus straight) is determined by the shape and structure of the hair follicle (a curly follicle versus a straight follicle), among other factors. Human hair can vary in ...

Asymmetrical follicles yield hair that curls, symmetrical follicles yield straight hair. The longer curly hair grows, the more complex its structure can be, says a study reported in a journal of ...

Humans are hairy, and sometimes that hair pops up in places we’d rather it didn’t. Consider unruly chin hair, which is ...