This book is part of a book series called How Science Changed the World .

This book has been graded for interest at 12-17 years.

There are 80 pages in this book. This book was published 2018 by Referencepoint Press .

Kathryn Hulick is a freelance writer, editor and former Peace Corps volunteer. She writes regularly for Science News for Students and Muse magazine. She has also published numerous nonfiction books on topics such as video games, artificial intelligence, energy technology and dinosaurs. Hulick's favorite part of writing about science is getting to speak with researchers in many different fields. Once, she spoke with an expert on parallel universes while he was shoveling snow from his driveway. Another time, she called a biologist who was out in the field in Africa, watching a herd of elephants. In addition to writing, she enjoys hiking, gardening, painting and reading. Hulick lives in Massachusetts with her husband, son and dog.