Despite the fact that those not very familiar with the subject will have much of the content go over their heads, this is perhaps the only place (in 1998 at least) that all this information is available in one, organized book. For that reason alone, it is an excellent reference.

My other complaint (in addition to the possible comprehension difficulty) is the evolution element is not always as prominently discussed and integrated as the title and preface suggest. Plenty of information on cells and embryonic development are covered but the evolution tie-in occasionally is lacking or at least not as strong as it could be.

There are several main themes in this textbook. Given the length, of over 600 pages, I will only go over a couple of them here. First is the conservation maintained in flexible biological mechanisms and organisms. As ironic as it may seem on the surface, conservation is a key part of the diversification process. While the morphology of species fills much of the imaginable spectrum (i.e. there is great diversity), the differences in genes, processes, body parts/positioning, and inter-cellular communication are relatively constant through millions of years of evolution. For instance, the three-dimensional structure of the a clam hemoglobin can be superimposed almost exactly on that of the 'same' myoglobin in a sperm whale. Likewise, with body plans, whether you are dealing with a goose, a mouse, a newt, a zebrafish, or Xenopus the site of the forelimb or pectoral fin is at the anterior boundary of the Hox-c6 and Hox-b8 expression compartments. Somewhat similarly, whether you are looking at a whale, a human, or a giraffe, you are looking at a species with seven cervical vertebrae. Of course each of those in the giraffe is longer than all seven of the human's combined.

The other main theme is that of the evolution of evolvability. Although individuals aren't selected to be able to 'better evolve', populations and species are. In addition, the systems that make up organisms (especially when the systems were in their infant stages hundreds of millions of years ago) are specifically selected for based on their flexibleness, versatility, and robustness. The immune system is one example that is gone over is ample detail.

Also of interest, but not necessarily main themes in the book, are things like the development of the nervous system (which relies on superfluous growth and functional selection rather than pre-programmed, exact genetic function), probable causes of the Cambrian 'explosion' (somewhat related to the evolution of evolvability above), time-dependent gene expression, and neural crest cells (which allow for 'rapid' diversification of the size and shapes of skeletogenic elements).

For those who are looking for a rebuttal to creationist propaganda, you will find tons of ammunition here. Besides the attacks that have been made by creationists on the immune system other topics like the evolution of eyes are discussed. Species like Anableps anableps, the 'four-eyed fish', and cubomedusan jellyfish, which have no brain but do have camera-type eyes (unlike the less useful reversed-retina human eyes), will leave creationists scratching their heads and wondering where their creator went wrong in creating humans. I don't think the authors intended the book to be a direct response to Michael Behe but their allusions to Black Boxes being opened in the final chapter let the reader know that the god-of-the-gaps theory Behe postulates is only plausible when all the evidence isn't carefully examined.