Darwin's Finches

"No field of study has been so dominated by the thoughts of one man..."
- Jonathan Weiner, The Beak of A Finch

I was really glad to hear that the Ann Arbor Library has chosen Jonathan Weiner's The Beak of the Finch for Ann Arbor/Ypsilanti Reads 2006. This promises some really interesting discussions and events centered around evolution. Given recent events in Pennsylvania and Kansas one really wonders where this country is headed. Ann Arbor thanks to its proximity to the University is quite a liberal town, which explains that there were no demonstrations outside the library and the book decision was generally welcomed. On the library blog, one of the members commented that Ann Arbor should have a book drive and donate copies of this book to places in Ohio, Iowa, Kansas and Pennsylvania where they need it more. It seems ironic that Jonathan Weiner lives in PA.

This book has been around for quite sometime and it won the Pulitzer Prize in 1995 and I feel that a 'second-act' for this book is much needed in these dark ages. It describes evoltionary theory with the backdrop of the fantastic study undertaken by the husband and wife team of Peter and Mary Grant. They have visited a remote island (Daphne Major) in the Galapagos Islands year after year (for more than 30 years) painstakingly studying Darwin's finches. They have branded almost every bird on the island and have collected every possible statistic about these birds over the years. Most readers, like me, will be surprised to know that till the Grant's began their research almost 30 years ago there was no real experimental proof for Darwin's Theory. This was a serious gaping hole in arguing the case for evolution. Darwin never saw evolution actually occur and the Creationists were justified to call it 'Only a theory' and they went on to say that, "... believers in evolution and creation must accept either view by faith."
The Grant's work on the finches is one of the most intensive and valuable studies ever conducted and is the best and most detailed demonstration of the power of Darwin's process. Their most startling conclusion is that evolution occurs 'daily and hourly' and not after a long passage of time, that it cannot be humanly observed, as Darwin himself thought. Weiner lucidly explains the pressures of sexual and natural selection, the fusion and fission forces that dictate the formation of a new species and how G.O.D. (generation of diversity, hah!) works. The book is also full of anecdotes about Darwin, his 'bulldog' - Julian Huxley and other colorful characters who have dotted the evolutionary studies landscape over the years. He also tells the story of how J.B.S. Haldane coined and defined the unit of evolution 'darwin'. He also describes some interesting parallel experiments carried out by Endler on tropical guppies and other studies by Dolph Schluter in Canada.
I liked Wiener's approach in writing this book. He provides a good background of the history and interestingly describes the 'scientific process' in action. He has maintained the focus on describing the Grants' work and evolutionary theory without slinging mud on creationism or debating the issue other than referring to it in passing. There are only two faults, if any, with the book. One, is that recent popular work on this subject by Dawkins, Gould and other merits not more than a couple of paragraphs; second, the long bibliography is appreciated but a short list of more accessible sources under Further Reading would have been more helpful for more enthusiatic readers. This is an extremely well-researched book and a must for anyone wanting to quote some solid facts about evolution to creationists and their pseudo-scientific cousins who believe in 'Intelligent Design' (such a cleverly coined misnomer!). It is a good read even if you are not really into pro-evolution militancy and proselytization campaigns like me.


Kaushal said...

Hi Hirak,
Talking of Darwin, "The Ancestor's Tale" by Richard Dawkins is also an interesting read.


Hirak said...

That and The Blind Watchmaker are next on my list.

laconic2 said...

See the article by Antonio Lascano (a biology professor in Mexico) which appears in Science magazine November 4 2005: abstract at http://www.sciencemag.org/cgi/content/summary/310/5749/787?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=evolution+mexico&searchid=1133055236212_8990&stored_search=&FIRSTINDEX=0&issue=5749
As Lazcano explains, the irrational fundamentalist opposition to Darwin's fertile idea has not taken root there, except when it has been exported to Mexico from the U.S.


Hirak said...

Thanks Laconic,
That was a great link! It rid me of a grave misconception. Really glad to hear that Mexicans have a better environment than people in OH, PA and Iowa.

Ashutosh said...

Rather than as the land of plenty, I have started accepting the US as the land of utter contradictions, where the most educated people co-exist with the most primitive, much more primitive than the Indians who they ousted from their land. Unfortunately, these primitives are in positions of great power.
Sometimes, I just don't know whether to continue being a vocal critic of creationism, or simply to ignore these bigots because they are so utterly ignorant and stupid so as not to even warrant attention from us. Even through a preliminary purview, any educated scientific layman can instantly find out that they do not know the first thing about what constitutes science and the scientific method.
One of the very best, lucid, and inclusive articles against creationism (oops...sorry, I mean 'Intelligent Design') that I have read is by the admirable and brilliant anti-creationist Dawkins:


Joey said...

wow ashutosh, the way you talk about the uneducated "stupid" people/creationsists who don't deserve your attention is what i would expect from a graduate student like yourself, thinking you're smarter than everyone else. you sound very elitist to me and i'm sure to anyone else who read your comment.
i'm a few months from finishing my PhD in Analytical Chemistry at UCRiverside, which makes me more educated yes, but doesn't mean that everyone else who disagrees with me is a bigot and not on my intellectual level! geesh. i would say anyone who read your comment would think YOU are the hateful bigot.
onto the subject, which is Weiner's book. the following is from author Richard Milton: Weiner seems entirely unconscious of the scientific significance of his own reporting. He writes, "Back in 1983, for instance ... a male cactus finch on Daphne Major, a scandens, courted a female fortis. This was a pair of truly star crossed lovers. They were not just from opposite sides of the tracks, like the Prince and the Showgirl, or from two warring families, like Romeo and Juliet: they belonged to two DIFFERENT SPECIES. Yet during the chaos of the great flood, they mated and produced four chicks in one brood."
Not only did the finches in question mate successfully, their offspring proved to be among the most fertile that the Grants recorded during their twenty years on the islands. The four chicks of this mating produced no less than 46 grandchildren.
The Grants recorded many other pairings of "different species" of finch, which, like ornithologist David Lack before them, they dubbed "hybrids". But of course the central significance of this finding is that the identification of the 13 varieties as different species is impossible to maintain once it is admitted that they can interbreed and produce fertile young.
The fact that different varieties prefer not to mate is very different from saying that they are unable to do so. Great Danes do not usually select toy poodles as potential mates (and vice versa) but they are capable of bearing fertile young if mated and are members of the same species, Canis familiaris. Arab stallions do not normally select Shetland ponies as mates, but they are members of the same species, Equus callabus.
Moreover, the Grants' observations undermine another myth about Darwin's finches - that individual species are "confined to certain islands". In order for different species to mate, they clearly have to occupy the same territory. Other visitors to the Galapagos have confirmed that this is this case. Television documentary filmmaker Gillian Brown spent a year working at the Darwin Research Station on the islands. It is common, says Brown, to find the different species all over the archipelago, rather than obeying the colored territorial maps drawn up by Darwinist ornithologists.
In almost all respects, the finches of the Galapagos are so similar that it is difficult to tell them apart. Indeed, Weiner himself remarks that, "Some of them look so much alike that during the mating season they find it hard to tell themselves apart." This mirrors David Lack's observation that "In no other birds are the differences between species so ill-defined." The finches all have dull plumage, which varies from light brown to dark brown, all have short tails, all build nests with roofs, and lay white eggs spotted with pink, four to a clutch.
It is very difficult for an objective observer to see how a group of finches who "find it hard to tell themselves apart", and who do in fact interbreed, can legitimately be called different species.

What is the scientific basis of this identification?