Richard Walker, BSc, PhD, trained originally as a zoologist and gained his PhD in physiology and biochemistry. Richard taught both secondary school and university students for a number of years before embarking on a successful career as a writer and consultant. His books include Kingfisher Knowledge: Human Body (Kingfisher, 2006), Your Amazing Body (Carlton Books, 2008), and Eyewitness Human Body (Dorling Kindersley, 2009).

Mark Ruffle was born near Bristol in 1973. He graduated from the University of the West of England with a degree in graphic design in 1995. After leaving college, Mark worked as a visualizer, and then in 1997 started working for Oxford University Press as an art buyer. Mark has been freelancing since 2000 and has enjoyed working for a wide variety of clients including Aardman, producing illustrations for Flash. He has designed and illustrated web content for the BBC to accompany television programs such as Hustle, Holby City, and Bleak House. Mark works in Adobe Illustrator and is equally happy drawing illustrations for books, packaging, advertising, or animation.

Galia Bernstein was born and raised in Israel. She started as a designer and illustrator in the Israeli's army magazine when she was 18 years old. After her service ended, she worked as a designer and art director in children's magazines and started illustrating books and writing comic strips for kids. She moved to New York to study illustration at the Parsons School of Design, and today she lives in Brooklyn. She is represented by NB Illustration in London, UK ,and works with clients all over the world, including Candlewick Press, Franklin Watts, Ladybird Books, Sterling Publishing, Pearson, Oxford University Press, Scholastic, and Macmillan.