Detour: To the Galapagos Islands

This fall, when I started this project, one of the books I read is one I bought years ago: The Beak of the Finch: A Story of Evolution in Our Time, by Jonathan Weiner.  It won a Pulitzer prize the year it came out, 1994, and received high praise from all who reviewed it, with good reason: it's a wonderful book.  Not only is it well written, it's revelatory. I thought I understood evolution before I read this book, but after reading the book, I realized I had only the barest notion of how species change.  What I discovered from The Beak of the Finch is that the process is much more complex and much more exciting than I could have ever guessed.

The author, Jonathan Weiner, tells the story of two scientists, Peter and Rosemary Grant, whose work with finches on the Galapagos Islands (Darwin's finches) began in 1973 and continues to this day.  Every year they spend months on the tiny barren islands out in the Pacific, intensely studying the finches who live there. They observe, measure, weigh, and tag the birds, recording and processing all the data, writing up the results.  After all these decades, they have gotten to know many generations of birds. And by know I mean intimately; they know them as individuals--when they are born, when and with what bird they mate, where they nest, the number and identity of their offspring, and when and by what means they die. Each bird is noticed, cared about throughout its life, mourned at its passing.

The book interweaves the story of the Grants with Darwin's story, and compares what he started to learn back in the 1830s with what the Grants have learned from their 20th century study--that the finch's beak (and other physical characteristics) is crucial to its survival, and that it changes over the course of generations of finches. That might not seem too earth-shattering a conclusion. After all, changes occur over generations in all species.  Humans as a group have become taller, for instance, in the centuries since Shakespeare's time. But what the Grants learn is that these changes are not just variations, but constitute the creation of new species of finch whose members don't mate with one another. And these different species exist simultaneously, sometimes diverging widely from one another, other times merging back into a single species.

But to me, that wasn't the most exciting revelation of the book. What I found the most eye-opening was the understanding that not only do such changes occur, but that they occur very quickly--not over eons but years, months even, especially for species who reproduce 4-5 times a year and mature in a matter of weeks as the Galapagos finches do.  And that this change from one species to another can just as quickly change back, can in fact change back and forth many times over decades so that the resulting finch seems hardly altered but is in fact the product of many back-and-forth fine tunings driven by environment and the struggle to survive.  We don't "see" evolution happening, but nonetheless it is happening all around us all the time.

This understanding made me look at human evolution in a different light.  I began to wonder whether the different early humans from millions of years ago were not successors but contemporaries, trying to survive in the same environment at roughly the same time. Maybe, instead of one human species triumphing over another as some paleontologists have theorized, the two species instead merged to create a third species that continued to change back and forth over the eons, diverging and merging, adapting to the changes in the earth's environment, even perhaps to our current era. (Could the Yeti, Sasquatch, Abominable Snowmen be in fact other human species?)

But how does Beak of the Finch fit with the controversy of evolution vs. creation that still continues? Well, I think it adds depth to the discussion.  We can't deny that changes occur in nature, whether you call it evolution or not. I believe there's room for the argument that God created nature with its built-in capacity to adapt and change, sometimes in a monumental way.  But that's a topic for another post.