Dr. Andrew Wilson FRSE was a Scottish physiologist and zoologist and lecturer in zoology and comparative anatomy at the University of Edinburgh and the Royal College of Surgeons of Edinburgh in the late 19th and early 20th century. In the preface of this book, he writes: "...the chief aim of the work is to present in a popular and readily understood form, the chief evidences of the evolution of living beings. In this view, whilst I have been content to assume the reality of that process, I have also endeavoured to marshal the more prominent facts of zoology and botany, which serve to prove that evolution, broadly considered is not merely a name for an unknown tendency in nature, but is an actual factor in the work of moulding the life with which the universe teems." - Summary by J. M. Smallheer