Evolution extends into plant and animal sections. However, the presentation of origins is less dogmatic than most of the reviewed texts. Chapter 1 gives the impression this is a health rather than a biology course. Illustrations are well integrated into text. Very heavy on dealing with environmental problems.
Evolution runs throughout entire text.
Origins is presented as fact. The word 'theory' is used differently by scientists and the general public. In biology, the theory of evolution is so broadly supported by evidence that biologists accept it with as much certainty as they do the theory of gravity. For example, the ability of your eyes to focus, the way your hands grip objects, your upright posture, your large brain, the color of your skin and numerous other characteristics are all results of evolution by natural selection. The first organisms to appear on the planet were bacteria, which are single-celled prokaryotes.