November 19, 2007

THERE'S NO SUCH THING AS SPECIES:

Documented proof of Darwin's natural selection (Terry Glavin, November 15, 2007, Straight.com)

Although Darwin could show that evolution by natural selection must be the answer, he couldn't present evidence for that answer in even a single case of evolution by natural selection, observed and documented in the "natural" world. No one, least of all Darwin, had ever seen it actually happen.

As a consequence, long after Darwin's theory had come to form the theoretical basis for the biological sciences, there was still an embarrassing dearth of experimental research into evolution. It was still, outside of science, just an "opinion". While Darwin explained how the "natural" world worked in theory, no one, even into the 1970s, had been able to fully and methodically document and describe having actually seen it work that way in practice.

This is where Peter and Rosemary Grant come in.

Peter and Rosemary, both from England, met at the University of British Columbia in 1960. They soon married, and both went on to work as professors of evolutionary biology at Princeton University. Now both 71, the Grants are among the most successful and important collaborations in the history of science. In 2005 they won the coveted Balzan Prize, which is equal in prestige to the Nobel Prize and brings almost three times the cash: the equivalent of about $3 million in Swiss francs.

The Grants have produced a body of research that is so exhaustive, so exacting and thorough, that many ornithologists fear it will never be replicated. The object of the Grants' obsessions is Galápagos finches. These are the birds so closely associated with Darwin that they're commonly called Darwin's finches.

It was Darwin's encounter with the archipelago's 13 finch species in 1835, during his five-week Galápagos sojourn as the naturalist aboard the Beagle, that caused his epiphany and produced evolution's great eureka moment. That's the legend, anyway.

The truth is it was long after his return to England, and after the specimens he'd collected had been properly classified by British taxonomists, that the significance of the birds, and of all those other peculiar endemic species he'd found on the Galápagos Islands, began to dawn on Darwin.

It wasn't until Peter and Rosemary Grant began making their annual pilgrimages to the Galápagos island of Daphne Major, a forbidding place of black lava and hellish summers, that the finches began to fully reveal themselves to science.

The Grants began their fieldwork on Daphne Major in 1973. They've put in 35 field seasons, and they're still at it. (The Grants will be presenting an overview of their most recent findings in a free lecture at the University of British Columbia on November 20.)

The Grants have documented the phenomenon that Darwin could only surmise by deduction and conjecture. It turns out that the mechanism of evolution can be observed moving through nature, not just in a laboratory or in a human-altered environment, and it doesn't always move at a glacial pace. The Grants have watched it happen, up close.

Biologists Rosemary and Peter Grant have spent 35 field seasons observing how natural selection has resulted in the evolution of Galápagos finches.

Specifically, what Peter and Rosemary have done is present the world with a rare and dramatic glimpse of variation caused by natural selection from one generation of animals to the next. And down through several generations of Galápagos finches, from different species, they've shown how heritable traits are "selected" so as to result in evolution.

As evolution occurs, even when it occurs quickly, it's usually barely detectable. The tiniest change can mean survival or extinction. In the case of the Galápagos finches, what matters is often barely measurable changes in the size and shape of the finches' beaks.

"That's the really difficult thing to do," Peter told me the other day. "You don't want to try it with earthworms."

It isn't that Darwin's theory had not been shown to work in practice before the Grants. It's just that no one had documented it in nature so completely and methodically.

Before the Grants, the case of the English peppered moth was one of the best-known studies of natural selection driving evolution. But the story of the peppered moth unfolds in a completely human-altered environment. Its observed evolution was in response to the rise and decline of the Industrial Revolution.

Prior to the advent of the "dark satanic mills" and the clouds of coal smoke and ash that settled over the English countryside, peppered moths were light-coloured, with specks and streaks of black, a colour scheme suited perfectly to camouflage because of the moths' habit of alighting and resting on tree trunks, on similarly coloured lichens.

In the poisoned air of the Industrial Revolution, the lichens diminished in abundance and trees were commonly blackened with soot. This trend favoured a black-coloured mutation in peppered moths and caused the light-coloured moths to nearly disappear. In recent years, however, with the decline of both factories and coal power, the light-coloured moths have become dominant again.

Nowadays, evolution by natural selection is being observed in "the wild" among sticklebacks in British Columbia coastal lakes, among fruit flies in South America, and also in laboratories, on an hourly basis, around the world.

In his Pulitzer Prize–winning The Beak of the Finch: A Story of Evolution in Our Time, a 1994 book about the Grants and the significance of their work, author Jonathan Weiner sets out the paradox of the persistent hostility to Darwin's "theory". Evolution denial is a common habit of some of Darwin's most privileged beneficiaries in the United States, almost always evangelical Protestants, whose wealth often depends solely upon Darwin being right.


Setting aside, for the moment, Mr. Glavin's deeply disturbing assertion that WASP's are actually a superior species to other human groups, let us note both that the best line in Mr. Weiner's book is about how fellow scientists joke that only God and Peter Grant can tell apart the finches that he claims are separate "species" and that, just as the moths failed to speciate in even the hoax version of the peppered moth experiment, so too do the various finches crossbreed rather freely, irrespective of their beak designs. In fact, what the immutability of species in these cases provides evidence for is the argument that no amount of natural selection will ever lead to Darwinism.


Posted by Orrin Judd at November 19, 2007 4:38 PM
Comments

I really do join with you in laughing at the Darwinists. My mirth is augmented by their perplexity over cultural evolution which very much follows the dictates of natural selection at every step, in contrast to biological evolution which cannot be demonstrated, and, well, is true because it just has to be so.

As to those finches, we all understand that those charletans are reporting measurable changes is the beaks of birds in a few generations because each tiny change is supposed to make the individual a slightly better feeder. The fools don't realize that such rapid improvements, if they really took place, were strong evidence of intelligent design. They are admitting that there is, somewhere, an idea, a substance, of a better finch for a particular environment.

Posted by: Lou Gots at November 19, 2007 6:27 PM

So lemme get this straight. The beaks are "evolving" at a rapid rate. From small beaks. Which must've been small and unchanging for tens of thousands of years. And it wasn't until these Grant people arrived that these birds needed larger beaks in order to become "more fit". Okay. Whatever. (And are they going to end up with beaks the size of Toucan Sam? )

But who are we to criticize them for finding a way to get their annual tropical vacation paid for that doesn't involve paying for it themselves? I wish I could pull off that scam.

Posted by: Raoul Ortega at November 19, 2007 10:05 PM

OJ likes to attack Darwin by picking at individual cases and not step back to look at the big picture. Yes, scientists are human and thus prey to folly and ideological blindness.

But what's the alternative theory? Do you honestly think God is directly responsible for every characteristic of every living thing? Is it "intelligent design" to give humans a vestigial tail? Or create whales as seagoing mammals with hip bones and leg bones but no hips or legs? Did God plant a false fossil record in order to trick us into thinking evolution occurred? Is God such a micromanager that (e.g.) he decided 265 million years ago to invent beetles, and carefully developed them so that by now they constitute about a quarter of all know life forms, and about 350,000 species? (Or "types" or whatever you want to call them.) Was God lazy and leaving false clues when he decided than humans would share 98% of our DNA with chimps, and decreasing percentages with cats and rats and even coral?

Of course not. It would be entirely perverse theology. I think the Dawkins' of the world are being silly when they claim evolution disproves God, but it's just as silly for believers to think that they need to attack Darwin or evolution or science in order to defend God.

Posted by: PapayaSF at November 19, 2007 10:53 PM

PapayaSF invokes a commonly used evolutionary tactic -- "the rule against negative argument," i.e., you can't criticize evolutionary theory unless you present an alternative, combined with the implied dilemma that there are only two mutually exclusive choices, Darwinism or Creationism. I would contend that Darwinian Evolutionary Theory is flawed, with muddled basic concepts and (statistically) insufficient means to achieve the ends it proports to explain, that criticism of such a theory is good science, and that the lack of a suitable alternative flows from deficiencies in our knowledge and imagination, rather than proving the only theory we can conceive.

Posted by: jd watson at November 19, 2007 11:43 PM

Is evolutionary theory "flawed"? No doubt. We've only been studying the problem for a few generations, and life on Earth is a immense and complex problem.

But many basic principles seem to be well-established, and if you're going to claim that there are huge statistical or logical flaws to evolution, well, you'd better be able to cough up a good argument instead of just shooting spitballs from the back row, which is more or less what goes on around here on this topic.

So if one claims a scientific explanation is illogical, yes, it matters if the new explanation has even more logical flaws.

And no, it should be clear from my post that while I am not a Creationist, neither am I the supposed opposite, an atheistic Darwinist of the Dawkins camp. I'm not at all claiming there are only two choices here.

Posted by: PapayaSF at November 20, 2007 2:15 AM

That's not actually how science works. It suffices that Darwinism is wrong, as you agree, for it to be discarded. We don't need to know what's right.

Posted by: oj at November 20, 2007 6:48 AM

If there is a God, there was a creation.

Worship God or Darwin, but don't kid yourself.

Posted by: Randall Voth at November 20, 2007 7:26 AM
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