This book describes how evolutionary history is studied using several well-known examples and also using evolutionary trees. Evolutionary trees are analyzed and used to explain adaptive radiations of orchids and the diversification of bats over geologic time. Evolutionary trees and genetic evidence is used to infer when and from what ancestors terrestrial plants evolved and invaded land. Specific adaptations of early land plants led to the evolution of terrestrial plants and their success on land. Evidence about the ancestors and habitats of humans is used to infer and analyze the evolution of the human family tree, whose populations were subject to the same forces of evolution to which other species are subject. Human evolution was not linear, involved offshoot species that did not survive, and took many thousands of years. In contrast, evolution can be seen in just a few years or less in other examples, and analysis of the evolution of mechanisms of pesticide resistance in insects will be used to illustrate this rapid evolution.