"Darwin's finches are not like Michelangelo's Adam, who raises his finger languidly to meet the down-stretched finger of God: the first man, molded of clay, half-raised from earth, created in an instant. These birds are more like Michelangelo's Prisoners, the famous statues he left half in and half out of the marble, so that looking at them today we can almost see and hear the sculptor's chisel at work. The birds are alive and breathing, but they are unfinished; in the Galapagos the sculptor is still at work, measurably and demonstrably... The chisel is hard at work daily and hourly in every landscape on the planet." (p. 206-7)This winner of the Pulitzer Prize does not disappoint. Whether you are a beginner or expert when it comes to the subject of evolution will make no difference. There is something for everyone in this book even if the reader isn't all that interested in science or evolution prior to reading.
Weiner compares and contrasts what researchers Rosemary and Peter Grant and those who worked on the Galapagos islands see and find with what Darwin saw and found. Although the Grants' view is very different from Darwin's view in many, if not most, cases, they both support natural selection. For instance, Darwin believed evolution occurred over very long periods of time and generally moved in a set direction toward fitness in the same direction the environment was heading. The Grants found that the environment fluctuates much quicker and is, for the most part, less headed in a particular direction (with the exception of global warming which is fairly consistent in mean temperature movement but not so consistent in its effects on El Niņos and La Niņas). Because of the ebbs and flows of evolution, due in large part to the environment, it can be more easily witnessed and documented in real time, in some cases, than it can be through looking at the infrequently fossilizing instances of a given species over thousands or millions of years. As Weiner puts it on page 111
The closer you look at life, the more rapid and intense the rate of evolutionary change. The farther back in time you stand, the less you see.By making detailed measurements of the various finch species (and individuals) year after year, breeding pair after breeding pair, and generation after generation the Grants are able to see the species wax and wane between becoming more alike and more different. The differentiation episodes come about due to changes in the ecological factors that are ever changing.
If you are interested in the topic of speciation, this book (especially beginning on page 162) and Mayr's are must reads.
I was a bit surprised by how much of the book didn't speak of Darwin's finches. Many other "evolution in action" observed events and experiments are discussed. Those include Drosophila (fruit flies), crossbills, sticklebacks, sparrows, soapberry bugs, and more. Sexual selection is also covered as is evolution at the DNA level and co-evolution.
Don't pass up the chance to read this book. It will educate you; it will change you and the way you think about life. The Beak of the Finch should be at, or near, the top of everyone's reading list.
"All times seem special to those who live in them. But it is neither parochial pride nor shortsighted despair to say that our time is more special than others. According to the fossil record, only five times in the past six hundred million years has there been such abrupt havoc in the biosphere. Only five times have so many twigs and branches been lopped from the tree of life at once... We are altering the terms of the struggle for existence: changing the conditions of life for every species that is coeval with our own.from the publisher:
Never before was such havoc caused by the expansion of a single species. Never before was the leading actor aware of the action, concerned about the consequences, conscious of guilt. For better and for worse, this may be one of the most dramatic moments to observe evolution in action since evolution began." (p. 276-7)
On the Galapagos Islands Charles Darwin gave his first hint at his theory of natural selection, writing about the finches he studied there. In Darwin's time there was no proof of this theoretical mechanism for evolution. Indeed it would have been thought absurd to imagine observing it actually happen; the process was thought to take geological time spans.
Weiner, an outstanding science journalist, details research done in the last 20 years that proves otherwise. Biologists Peter and Rosemary Grant have documented the evolution of Darwin's Galapagos finches, demonstrating that it is neither rare nor slow, but can be watched by the hour. Weiner's superb account reads like a thriller and won the 1995 Pulitzer Prize for nonfiction.
On a remote outpost of the Galapagos, where Darwin received his first inklings of the theory of evolution, they prove that Darwin did not know the strength of this own theory. We watch as nature alters the beaks of finches from generation to generation to help them survive.
They explore evolution not as it occurred centuries ago, but as it's happening right now. Evolution in our time is charted in chapters which recount observations of evolutionary processes speeded by human intervention. A fascinating, revealing study. Includes 50 illustrations and a map.
"Spark(s) not just the intellect, but the imagination."
-- Washington Post Book World.