Book Review : Piecing Together Thoughts on the Origin of Evolution
Blueprints: Solving the Mystery of Evolution by Maitland A. Edey and Donald C. Johanson (Little, Brown: $22.95; 416 pages)
When Charles Darwin published “On the Origin of Species” in 1859, he wrought a fundamental revolution in the way humanity thinks about itself and all life. The psychological and theological resistance to this change was enormous, and in many places, the revolution is still not complete.
But as a scientific matter, there is no question that Darwin’s vision was right. There are still arguments about the details, but the overall scheme is as clear as the Copernican vision that the Earth goes around the sun and not vice versa.
One of the amazing aspects of Darwin’s work on evolution is that when he put forth his explanation of how living things progressed from single cells to human, he didn’t have a clue about the mechanism of heredity.
Here was a theory that argued that organisms randomly change into other organisms, but no one knew how this occurred, including Darwin. Gregor Mendel did not publish his work on heredity until three years after Darwin published his work on evolution, and Mendel’s work was largely ignored in his own time.
Nowadays, we know that microbiology is the key to biology. The action is all at the molecular level. In Darwin’s day--and until the last few decades--biologists dealt not with molecules but with whole organisms. They were taxonomists, not biochemists. They studied organisms, classified them and grouped together the ones that appeared related.
Molecular Basis
In the 1950s, 100 years after Darwin’s work, biologists figured out the molecular basis for heredity. Genes contain DNA, and DNA holds the secret. The physical attributes of every living creature are determined by its DNA. Change the DNA and you create a different organism.
It turns out that the closer two organisms appear on the outside, the closer they are on the inside. That is, Darwin classified organisms on the basis of how they looked, and, putting them together in this way, he argued that they evolved from each other.
Creatures that look similar have similar DNA. The more they look alike, the closer the molecular match. The more disparate they look, the more dissimilar is their DNA. Thus, it is reasonable to say that the discovery of the molecular basis of heredity was one of the most striking examples of confirmation in the history of science. It confirmed Darwin’s ideas.
All of this and much, much more is contained in “Blueprints” by Maitland A. Edey and Donald C. Johanson, a lucid account of evolution from the precursors of Darwin to the present day. Evolution is one of the most powerful ideas in the history of thought, and Edey and Johanson do justice to its sweep and strength.
A Simple Idea
Part of what makes evolution so compelling is that it is basically a simple idea. Edey and Johanson have built on that simplicity, taking the reader step by step from Darwin through Watson and Crick, the discoverers of the secret of DNA. This book is a must for anyone who has any questions about evolution or who wants to know how the pieces fit together. It captures the facts and the grandeur of a great scientific idea--and the many scientists who have created and shaped it.
Like most good science books today, “Blueprints” is as much about people and about the process of science as it is about the science itself. Edey and Johanson review Darwin’s precursors in a chapter, and then get to Darwin himself, who remains a transcendent figure in his own right. My interest in Darwin is never sated.
‘Neglected by Science’
Of Mendel’s contribution, Edey and Johanson write: “As Schubert was neglected in his life by music and Van Gogh by painting, so was Mendel neglected by science. This seems scarcely credible today, and yet it is just one more example of a rule often observed: Look at a problem from a totally new angle and people won’t so much disagree with you as completely misunderstand you.”
Watson and Crick are also well portrayed. The chapter introducing them begins: “We must learn the architecture of DNA--that is what a young man named James Dewey Watson thought.” I wonder how they know what he thought.
Though “Blueprints” is very well written, I have one minor complaint. The authors frequently include verbatim reports of their conversations with each other while they were writing. They carry on a dialogue about whether they have explained things properly or whether they’ve given too much emphasis to one thing or not enough to another. It’s an odd device that takes some getting use to.
But that’s not a serious complaint. The book is first rate all around. It’s a welcome contribution to popular understanding of evolution. It’s too bad such a book is still needed, and it’s too bad that the people who most need it probably won’t be reading it.
