The Beak of the Finch: A Story of Evolution in Our Time

It is said that God knows the fall of a sparrow, but Peter and Rosemary Grant know the fall of every finch on Daphne Major, a tiny uninhabited island in the Galapagos. For decades they have been conducting a meticulous study of "Darwin's finches", several closely related species of finches on the islands, and have conducted one of the very few studies tracking natural selection and evolution of vertebrates, or of any species in the field rather than in the lab. Every finch is banded and meticulously measured, and the change in various traits documented over the generations. It is impossible to read this book and not come away with an appreciation for the power of natural selection.

One of the details I hadn't appreciated is that show more evolution isn't just slow because changes are tiny, but because most of the time there are a variety of selective pressures pushing in different directions. The Grants observed a measurable and statistically significant change in the average beak size of the finches in response to a single catastrophic drought; however, a few years later, a massive El Nino produced another measurable effect in the opposite direction. So evolution dithers around the current average conditions, but several drought years in a row -- perhaps the result of climate change, for instance -- could produce a measurable effect much more quickly than I imagined.

This is engagingly written and well-aimed at the intelligent layperson who doesn't know the details of biology; it perhaps errs a bit on the side of caution (explaining the evolution of antibiotic resistance in bacteria, for instance, which is pretty well-known and could probably have been assumed), but overall I recommend it highly. show less

Five years ago I realized a life-long dream with a trip to the Galapagos Islands. It was a wonderful trip and we met a great group of people who we have stayed friends with ever since. They had read this book before they came and recommended it.

A team of evolutionary biologists, headed by Peter and Rosemary Grant, spent up to six months a year on the isolated island of Daphne Major studying the finches who live there. The differences between the species were noticed by Charles Darwin when the Beagle spent time in the Galapagos Islands. His theory of selection was, in part, based upon these birds. So they seemed a natural population for the Grants to study. During the time they were on the island there was one year of severe drought and show more one year of excessive rain. During the drought years the smaller beaked finches had trouble finding seeds to eat and many died out. Subsequently, larger beaked birds were observed on the island. Then when the rainy year came, the smaller beaked finches were able to get the softer seeds more quickly and they thrived. Based on their studies the Grants derived three main observations:
1. Natural selection is a variable and constantly changing process
2. It can be a quite rapid process, not taking millennia as Darwin thought.
3. Selection can change over time.

Jonathan Weiner explains the Grants' studies in clear language. He also extrapolates from their findings to those of other researchers that support and add to the studies. I learned so much about evolution and natural selection by reading this book.

The Grants are now based in Princeton University but they met at the University of British Columbia and they both worked at McGill University in the 1970s when they started their studies of the Galapagos finches. It seems that Canada lost out by not supporting their work enough. (Note: Weiner only associates them with Princeton; I learned about their Canadian connection from Wikipedia.) show less

This was a compulsory text for my class on Evolution during my undergraduate days, but it stuck firmly in my mind years after I moved on to other fields. Weiner's writing has a journalistic tone, but flows well and kept me consistently interested. He takes the mysticism out of Darwin's Theory of Evolution, describing key modern efforts to research speciation and clarify his ideas centuries after the HMS Beagle landed on the shores of the Galapagos islands. My one gripe with the book is its slight political slant, with anecdotes from researchers about one-upping religious zealots and a final chapter characterizing the bulk of the American public as closed-minded. A more tolerant approach could have opened up the audience to that same show more public. Otherwise, I highly recommend this book to anyone who wants a clearer understanding of evolutionary theory without the bulky textbooks. show less

I enjoyed this book and it had a lot of great insights, but I think it think it could greatly benefit from either a forward or an afterward about the changes that have taken place since it was written (1994). For example, the book includes a discussion of climate change and how it may affect the rate of evolution, but back then these ideas were much more speculative. There is also a discussion of the hole in the ozone layer, and how it is affecting the mutation rate of the species of algae that passed beneath it, but in 1994 the Montreal Protocol was only seven years old and its effectiveness was yet to be known. Twenty-three years later, there is evidence the ozone layer is beginning to self-heal and the hole is becoming smaller.

The show more context of 2017 also makes this quote all the more poignant: "We are altering the terms of the struggle for existence: changing the conditions of life for every species that is coeval with our own. 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." (page 277). show less

This book was simply phenomenal. The only thing stopping me from making it five stars is that some parts of it were filler content, which is largely unavoidable. However, it was incredibly interesting.

The book follows researchers in the Galapagos who are studying Darwin's finches. The excellent writing style breaks down complex research of evolutionary biology into something a 19 year old (me) can understand. This book completely changes the perspective on nature and the idea of a species: showing evolution not as a linear change over time, but as a constant adaptation to a cruel world. Something as simple as a finch's beak can waver back and forth in size as these islands go between droughts and storms every couple of years. The show more progression of any given animal is not a straight line in a specific direction, but rather a wiggling line that might move a certain direction as a long term trend, but also is constantly changing.

Anybody who wants to know more about Darwin's research and how it's still being expanded upon today, this book is worthy of the Pullitzer Prize that it won. If this review was a turn-off for you, then the book wouldn't be your kind of entertainment. But overall I definitely recommend this. Any book can make you learn, but not many books can truly stimulate you to think about something you'd never considered. show less

An interesting view of the Grants' study of finches in the Galapagos - and some fascinating implications, continuations, and conclusions drawn from the same. The first two-thirds of the book is a quite detailed description, including quotes and first-person reports, of the twenty-plus year (as of 1994, when the book was published) study of the finches on Daphne Major and other islands in the Galapagos; the methods used to determine variation (beak measurements, mostly), the results of odd weather - drought and flood - on the finches and their variation, and the interim conclusions drawn from analysis of this data. Then it goes on to discuss other analyses, revealing similar (though less visible, and overlooked until they knew what to show more look for) patterns of variation in response to events in other populations. Throughout, it's related back to Darwin's perception of evolution as slow, with the data contradicting that. Evolution happens constantly - it just, usually, flickers back and forth on a continuum, so looking at a distance there's no great change. When situations continue to lean one way, changes become stronger, more widespread and more permanent...for a limited definition of permanent, since the flicker of changes continues. I spotted the link to diseases half a chapter before it was directly discussed, but once it was mentioned it was covered quite thoroughly. All in all, a fascinating book, that makes sense out of a good many things I knew but didn't see patterns in. This is one that will permanently change my view of the world. show less

A well-written look at contemporary evolutionary scholarship, mostly focused on the long-running detailed studies of Galapagos finches, but extending to work on guppies and moths and bacterial evolution as well. Weiner constantly brings the focus back to how the current work relates back to what Darwin himself thought and wrote about, which I thought a pretty effective stylistic device. Weiner ably conveys the way that evolution by natural selection actually works in practice, and that alone would make this book worth a read.