In the Introduction, Mark Kurlansky broadly outlines the scientific terminology of the animal world (kingdom, phylum, class, order, family, genus, and species) and explains biodiversity as it relates to Darwin’s theory of evolution. He provides historical context and introduces the scientific foundation on which he bases his arguments. The problem we are facing, he explains, is that within 50 years, the fish most commonly eaten by humans (such as salmon, cod, and tuna) could be gone. Their disappearance would significantly alter the entire food chain and have devastating results not just for the oceans but for birds, animals, and people on land.

In Kurlansky’s brief introduction to Darwin’s theory of evolution, he explains that humanity is not separate from nature. Darwin saw nature as “a cruel system in which species attempted to kill and dominate other species in order to secure the survival of their own kind” (13). In this struggle for survival, variance among species allows some to survive while others go extinct. Tiny changes in environmental circumstances—such as temperature or the introduction or removal of a new species—can completely alter the natural order of an ecosystem.