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

Ok, so my post from yesterday might have a few caveats.  As it turns out, some wild animals *do* change right before our eyes, generation to generation.  And the implications of these changes can change how we see our world.

When I did my book review of Beaverland, I mentioned how some species are keystone species not only in a biological sense but also a cultural and historical sense, having an outsized impact on our own species.  A suppose that a subset of that could be species that have had an outsized impact on science.  Among those are a group of a dozen or so largely unimpressive-looking little birds that flit about a group of volcanic islands out in the Pacific.  Their unique scientific importance might never have come to light, if not for an inquisitive British naturalist looking through the specimens he collected from his one memorable voyage away from his homeland.  That biologist, of course, was Charles Darwin, the birds were the finches of the Galapagos Islands.

In the Pulitzer Prize winning The Beak of the Finch, science writer Jonathan Weiner tracks the decades-long study of the finches of Daphne Major (one of the least-visited islands of the Galapagos) by husband-and-wife biologist team Peter and Rosemary Grant, along with generations of their grad students.  Camping out for months at a time in a harsh, unforgiving landscape, the Grants and their students came to know the finches of their island like a shepherd knows their flock, and devoted years to tracking the slight changes in the shapes and sizes of the birds beaks in response to years of extreme weather, including back-to-back drought and flood.  Taking careful measurements, the Grants were able to provide key insights into how species change in response to environmental conditions.  Processes that Darwin thought would be too slow for scientists to ever document were playing out in real time.

A simple ecosystem with a limited cast of ecological characters neatly isolated from the rest of the world, Daphne Major provides a near-perfect laboratory setting for studying evolution in action.  Weiner's book provides an excellent overview of Darwin's Theory of Evolution through Natural Selection, as well as how the findings on finches in the Galapagos have implications for modern life.  For example, the same forces that sculpt the beaks of birds off the coast of Ecuador are also impacting our own lives through penicillin-resistant bacteria and insecticide-resistant pest species.  

One aspect of the story that I found particularly fascinating was the documentation of the birds' responses to two back-to-back terrible weather events - a drought, followed by torrential rains.  Weiner tells us that these rare weather events for the Galapagos are becoming more and more common, pushing the birds' ability to adapt and survive to the limits.  Darwin's finches, simply by stranding themselves on the Galapagos, surviving, and diversifying to fill various niches, helped to inspire the theory that changed the way we view the natural world and our relationship and place within in.  The question remains to be seen as to whether they'll be able to survive the changes that we are wreaking open the world we share.

The Beak of the Finch: A Story of Evolution in Our Time at Amazon.com