This item first appeared in the August 2009 issue of The North Texas Skeptic.
The Beak of the Finch
1995, Vintage Books, 303 pages
I discussed Icons of Evolution by Jonathan Wells back in 2002. In the book Wells posits ten of what he calls icons-signature points upon which Darwinian evolution is supposed to hinge.1
Wells’ ten icons are:
Darwin’s tree of life
Homology in vertebrate limbs
Four-winged fruit flies
In the case of the peppered moth, Wells significantly points out photos of peppered moths resting on tree trunks or tree bark. The point is this: Published research reported on the effect of industrial activity on moth populations. There were moths of a peppery light color and moths with a peppery dark color. When our industry produced a lot of soot in the air, tree trunks (and everything else) acquired a dark grey coating. Moths of a lighter color stood out for all birds to see, and the moth population shifted to the dark end of the scale. When industry stopped pumping soot into the air, trees returned to their natural, lighter color, and dark moths lost their advantage. Researchers posted this as an example of natural selection in action.
In his book, Wells took great offense with these photos and disclosed the awful truth-the photos were staged. Dead moths were stuck on the trees and photographed to fool students into believing in Darwinism.
In this instance, the magnificent brain of Jonathan Wells, Ph.D., showed its power. I had completely missed this point when I viewed the photos in an earlier life. I had naively assumed a photographer was given the assignment to show students how moths of different colors looked when posted on bark of different colors. So the photographer got some moths, killed them, stuck them on some bark, and took the photos. It never occurred to me this was all a scheme to fool innocent students.
Wells is a senior fellow at the Discovery Institute Center for Science and Culture. The CSC is the major propagandist for Intelligent Design, a modern variation of creationism. Intelligent Design, they assert, is well supported by science and should be seriously considered as an alternative to purely natural mechanisms, such as Darwinian evolution. It would appear there is a thunderous clash of scientific viewpoints brewing.
Twenty years examining the Intelligent Design movement shows zero scientific activity. There have been symposia, public debates, slick video productions, and also books. Besides Icons we have Darwin’s Black Box, The Edge of Evolution, Mere Creation, Intelligent Design: The Bridge Between Science and Theology, The Privileged Planet, and a number of others that presume to provide scientific support for Intelligent Design or against Evolution. The CSC also claims two papers published in real, peer-reviewed scientific journals.
For example, a few years back CSC director Stephen Meyer arranged with Intelligent Design sympathizer Richard Steinberg to publish a review article in a journal for which Steinberg was editor. Steinberg side-stepped the normal review process and published “The Origin of Biological Information and the Higher Taxonomic Categories” (Proceedings of the Biological Society of Washington 117 (2004): 213-239). It’s what it takes to publish pseudoscience these days.
Videos include Icons of Evolution, Unlocking the Mystery of Life, The Privileged Planet, and also Expelled, No Intelligence Allowed. The later title may not have a CSC connection, but it shows TV personality Ben Stein connecting Darwinism with Nazism and the Holocaust.
Isn’t doing science wonderful? It’s an idyllic armchair world of publication, and presentation. And no sweat.
Not quite. The Beak of the Finch presents the world of real science.
For over 30 years beginning in 1973 Peter and Rosemary Grant worked studying the finches on the Galapagos Islands. One hundred and seventy years ago the Galapagos finches gave Charles Darwin inspiration during the development of his theory of evolution. Finches (dead) he brought back from the voyage of the Beagle turned out to be variations with a common ancestry. They were different species of finches that developed only on the Galapagos. Darwin’s finches represent one of Jonathan Wells’ icons of evolution.
Spending six months out of every year for years on end in the Galapagos, the Grants and others on their team carefully cataloged every finch on a small island and observed as populations hatched and died. They caught the birds and measured their beaks and noted their individual songs. Did I mention they measured the beaks to a fraction of a millimeter?
There were no armchairs in their camp, to say nothing of running water and air conditioning. The equator runs right through the small Galapagos cluster, and there is often no rain for months. The sun is blazing hot. The Grants raised two daughters in this environment, alternating with stays back at Princeton University to lecture and to publish.
And Wells sees fit to critique the Grants’ work.
The Grants, observed Wells, did not observe any speciation. Nor did they see any net evolution within a finch species. When extended dry spells forced the finches to crack harder and scarcer seeds, the population shifted to birds with thicker and tougher beaks. When the rains returned, and the variety of food increased, the tough-beaked birds gave way to ones with more adroit beaks. No net change, Wells observed.
Wells did not mention other research covered in The Beak of the Finch, which is not to imply he based Icons on Weiner’s book.
The Beak of the Finch covers more than beaks. In the streams of Venezuela, Margarita Island, Trinidad, and Tobago guppies are in their natural environment. They swim about the quiet ponds, but always close to the bottom, because they have enemies in the form of several species of fish and a freshwater prawn. The stream beds are often carpeted with multi-colored gravel, just as in your aquarium, and guppies that look like the speckled bottom of the stream live to spawn another day.
About the time the Grants were studying finches in the Galapagos, John Endler was doing a similar study of the guppies. He noted that in the head waters of a stream there might be few predator fish, but as a stream neared the sea after traversing a number of water falls, the guppies’ enemies grew in number and variety. The predators that were downstream could not get up the water falls, so upstream guppies enjoyed less predation.
Endler noticed that as predation increased downstream, so did the pressure of natural selection. Where predators came in numbers guppies that did not well match the stream bottom became quite rare. In regions where the streams don’t have colored gravel bottoms, the guppies have a problem.
Bold spots may show off male guppies to potential mates, but the boldest males get seen and eaten before they can spawn. Spotless males can avoid getting eaten, but they also avoid getting spotted by female guppies on the prowl. Endler observed that successful guppies were ones that struck a careful balance. Their spots were quite small and escaped the view of predators several inches away. However from the distance of a couple of centimeters they showed up on a female’s radar and remained in the gene pool.
Endler took the experiment a step further and constructed ten artificial guppy ponds at Princeton University. He seeded the ponds with guppies and let nature take its course. The guppy populations took off, and Endler introduced the guppy predators into the experiment, selectively. Some ponds did not get predators. Also, Endler provided different gravel bottoms for the ponds and studied the results. Natural selection took place.
Populations under the pressure of predation conformed to the requirements of survival, matching the gravel bottom and cautiously displaying spots for the female sex. Populations free of predation developed gaudy spotting in a race with sexual selection.
There’s much more. Jamie Smith conducted research with sparrows on the island of Mandarte in British Columbia. British Columbia does not suffer the drought and the equatorial heat of the Galapagos, but it does have seasons of severe wind, snow, and cold. This research again revealed clear population response to the pressure of natural selection.
If the book illustrates one thing it is this: Contrary to what some creationists assert there is on-going and fruitful research into Darwinian evolution. Real scientists are working in the real world and doing real research with little opportunity to enjoy an armchair. The contrast with the lack of activity by the creationists is breath taking.
For the record, despite what Jonathan Wells had to say about the peppered moths, in the case of the finches he agrees that natural selection does work. Additionally, published research does not claim the finch studies offer proof of speciation or net evolutionary development. One wonders, then, what was all the fuss with Icons of Evolution.
On a final note, if the Grants did not observe any net evolution of the finches during their research, they must have observed the remarkable evolution of technology during this time. When they started in 1973 there were no personal computers, and the book details their later work as they archived their data on large numbers of floppy disks. The Grants are now emeritus professors, and it’s fairly certain each of their personal computers will be connected to terabyte hard drives sitting on their desk tops. Readers who have observed the evolution of computers will have to appreciate the irony.
Jonathan Weiner received the Pulitzer Prize in 1995 for The Beak of the Finch. He has also written The Next One Hundred Years and Planet Earth.