For a ‘short introduction’ to the theory of evolution, this book certainly covers the right kind of topics, including: the process of evolution; evidence that it occurs; adaptation and natural selection; and speciation.
I did however find much of the prose regrettably heavy-going. Even—perhaps especially—when covering complex topics, introductory guides need to use plain language. At times, even though I consider myself relatively well-read for a lay-person on the subject of evolution, I struggled to understand what the authors were trying to say. Their prose is sometimes so succinct as to border on the incomprehensible. I tried, for example, to parse the following passage at least a dozen times, and I’m sure it’s making a very valid and important point, but I still cannot fathom what on earth it’s supposed to mean:
In less extreme cases, gradual geographical changes in traits arise because migration blurs the differences caused by selection that varies geographically, in response to changes in environmental conditions.
An important subject, but a missed opportunity.