Illustrated edition. By the hands of travel writer Gabi Martínez and archeologist, naturalist and explorer Jordi Serralonga, and illustrated by artist Joana Santamans, Invisible Animals takes us on a journey around the planet, searching for animals that almost no one has even seen. It describes extinct animals we cannot observe anymore as well as those still living that we never see or that are very hard to spot due to their ways of life and the harmful effect of humans on them and their ecosystems. This book explains academic concepts and data related to natural science in a language accessible for the non-specialist reader. It is both naturalistic and literary in spirit, as a catalog of what was and what could have been, of what can be, and what we wish to discover.