The Making of the Fittest: DNA and the Ultimate Forensic Record of Evolution
DNA evidence not only solves crimes—in Sean Carroll’s hands it will now end the Evolution Wars.
DNA is the genetic material that defines us as individuals. Over the last two decades, it has emerged as a powerful tool for solving crimes and determining guilt & innocence. But, very recently, an important new aspect of DNA has been revealed—it contains a detailed record of evolution. That is, DNA is a living chronicle of how the marvelous creatures that inhabit our planet have adapted to its many environments, from the freezing waters of the Antarctic to the lush canopy of the rain forest.
In the pages of this highly readable narrative, Sean Carroll guides the general reader on a tour of the massive DNA record of three billion years of evolution to see how the fittest are made. And what a eye-opening tour it is – one featuring immortal genes, fossil genes, and genes that bear the scars of past battles with horrible diseases. This book clinches the case for evolution, beyond any reasonable doubt. 50 illustrations; 8 pages of color.
About the Author(s)
Sean B. Carroll is an Investigator at the Howard Hughes Medical Institute and Professor of Genetics at the University of Wisconsin-Madison. His scientific discoveries have been featured in Time, U.S. News & World Report and The New York Times, and Carroll himself has written articles for Natural History and Playboy. His first book, Endless Forms Most Beautiful: The New Science of Evo Devo, was a 2005 Top Popular Science Book of the Year (USA Today). He and his wife and children reside in Madison, Wisconsin.
A Primer of Evolutionary Theory for Beginners, October 13, 2006
Richard Dawkins wrote a very enjoyable book titled The Ancestors Tale. It traces our evolution backwards, from humans, through apes and monkeys and so on, back to simple one-celled organisms. It tells the who of evolution: which species were descended from which. The Making of the Fittest tells the how and why: how variations appear in organisms and why they survive, or don’t. This is the story of natural selection. Darwin told the story, but a lot more has been learned since then, especially in recent decades, and Sean B. Carroll has been one of the discoverers. But, unlike many researchers, he can write a readable book for beginners.
Carroll focuses on DNA because that’s of prime importance. When DNA is copied, for the reproduction of the cell or the organism, the copy is not always exact. The new variant is usually harmful, but might be helpful. Carroll shows, using elementary arithmetic, why helpful variants occur and prosper much more often that most people would guess. Keep in mind that, when a bad gene does come along, the organism usually dies and the gene disappears from the pool. The good genes usually accumulate.
Carroll tells the story mostly through examples. For example, we humans are descended from animals that could see only 2 colors. Carroll tells of the duplication of the gene for one of the colors and the mutation of the second copy to react to a third color. (I simplify; Carroll tells more of the story.) Duplication and subsequent mutation of genes is very important in evolution. It allows organisms to develop new capabilities without losing the old.
Another important mechanism involves genes which control the expression of other genes. Even with no change in a given gene, a change that causes the gene to be expressed in a new place or at an additional stage in development can give rise to a new capability with no harm to the old. (Again I simplify.)
Gene duplication, changes in gene expression, and other mutations leave traces in our DNA and these give clues to our ancestry. This fact explains the book’s subtitle. More important to Carroll, these traces also demonstrate natural selection at work. To give a personal example, an examination of my genome would show that the gene which shuts off lactose digestion in adults had been knocked out by mutation; as a result, I have a source of nutrition that is not available to most humans.
There’s not much that one has to know to read this book. It probably helps to know that a gene is a segment of DNA and that the sequence of its bases determines the sequence of amino acids that makes up a protein. However, Carroll explains this. I haven’t been a beginner for a few decades now, but I think Making of the Fittest will be accessible to a bright high-school.
As elementary as it is, it still has information that is of interest to me. The most important concerns the evolution or the eye. (He doesn’t indicate the value of a cup-shaped eye: the animal can tell the direction from which the light comes by the part of the eye which isn’t receiving it. And an eye that has only a small opening can form a rough image even without a lens.)
Carroll says a lot about disproving creationist arguments. This is probably futile. Most creationists are convinced that they have a Higher Truth revealed to them by God Himself. This book will, however, be useful for people who accept creationism simply because they don’t know the science. And, of course, for beginners who are simply interested in the science.
For those who are interested in the material in this book and would like more information, there are a few books, ranging from elementary to advanced, which I recommend and which I have reviewed. Two are by Sean Carroll himself, on the topic of "evolutionary developmental biology; one is excellent for those who have absorbed the material in Making of the Fittest and the other is considerably more technical. Other books cover different related material. Click on "See all my reviews", above for the reviews. (There are 3 pages of them.)