a leaf on a tree, that tree would have 1 750 000 leaves. Since humans count for just one leaf on the tree, we have a lot to learn about the millions of other forms of life with which we share the world. A dazzlingly illustrated and child-friendly introduction to biodiversity, Tree of Life shows how living things are classified into five kingdoms --- and how each has much to tell us about all aspects of life on our planet.Tree of Life is part of CitizenKid: A collection of books that inform children about the world and inspire them to be better global citizens.