Lina Zeldovich makes sure to wear her “Pile of Poo” emoji hat for all public appearances, including this interview. The choice of attire is appropriate, since her just-published book is about poop, and specifically about how human excrement is dealt with around the world. The book grew out of Lina’s award-winning 2014 Narratively article, “The Magic Poop Potion.” In her book, The Other Dark Matter, Lina draws on scientific scholarship and her extensive reporting, and writes about initiatives to upcycle poop from around the world. We spoke to Lina about her inspiration to write the book, her meandering path into journalism and the advice she has for young writers.