Monday, July 26, 2010

Why Darwin Rejected Intelligent Design

In all the annals of evolution and also in references to Charles Darwin's seminal work (The Origin of Species) it is seldom mentioned that he was originally a creationist - and that he approached the origin of species from the creationist (or now, "Intelligent Design") standard. It is interesting to explore what transpired to cause him to change his mind. Briefly, we will see it largely had to do with his observations of assorted species during The Beagle's sojourn in the Galapagos Islands. Darwin basically found that the observations made couldn't be reconciled with creationist "theory".

Darwin was so imbued with the creationist perspective that he failed to collect one single species of giant tortoise present in the islands. Fortunately, the occurrence of other species - and their recording- ultimately held away with the assistance of a consummate taxonomic researcher: John Gould - an ornithological expert at the London Zoological Society.

For sake of brevity here, I will just touch on the assaying of two avian species: finches and mockingbirds. No less than 14 species of finches were recorded in the Galapagos and this eventually impacted Darwin's point of view. At the time, as with the giant tortoises, Darwin's cavalier creationist view led him to sloppy techniques and lack of rigor in recording observations. In particular, his creationist chauvinism prevented him from grasping (at the time he behled the finches in the islands) that they all might have evolved on different islands.

Indeed, had he already been privy to natural selection, and how adaptations operate within its purview, he'd have easily seen that the variety of beaks displayed among the finches was directly traceable to the sort of foods they ate, in the respective islands. In point of fact, 4 of the fourteen finch species fed on seeds (as finches generally do), and another two species consumed fruits, flesh and flowers of cacti. Seven other finch species were primarily insectivorous, while one fed exclusively on leaves. Thus, from his creationist disadvantage point, it wasn't suprising that Darwin was fooled to the extent of believing some of the birds weren't finches at all (Assisted by the fact they didn't particularly look like European finches).

Re: the mockingbirds, Darwin found four species on four different islands. Despite the drawbacks of his creationism, he was too consummate a naturalist not to notice that the birds were either distinct or separate species. In one of his journals, writing about them, he hinted at a natural selection basis but couldn't quite go the whole hog:

"When I see these Islands in sight of each other & possessed of by a scanty stock of animals, tenanted by these birds but slightly differing in structure & filling the same place in Nature, I must suspect they are only varieties...If there is the slightest foundation for these remarks the zoology of Archipelagoes - will be well worth examining, for such facts would undermine the stability of species"

Faced with an absence of critical information to resolve the issue, Darwin continued to be influenced by the creationist assumption of special, separate species - until he returned to England, on October 2, 1836. Three months later, he deposited his Beagle collection with the earlier mentioned John Gould. Darwin did not receive the full report of Gould's findings until March, 1837.

Then, Gould informed Darwin that 3 of his 4 mockingbird species were distinct - new to science - and different from all other known mockingbirds. He also notified Darwin that his collection included 13 or possibly 14 species of very unusual finches, all so closely related that Gould had categorized them in a single new group. In that brief exchange with Gould, all of a sudden the Galapagos had become their own special "center of creation". Darwin then found himself confronted by the problem of the origin of species he'd not been while actually there, imbued with his creationist mentality.

It would not be exaggeration to say Darwin was stunned by Gould's results. Indeed, if Gould was correct about the mockingbirds it meant that the supposed "barrier" between species had been broken by these birds on a set of isolated islands. Thus, gradual evolution through geographic isolation was the only plausible explanation that fit with the observational record (clarified by Gould, an expert ornithologist)

Gould's taxonomic analyses and insights into the Galapagos finches were also central to changing Darwin's creationist mindset. Again, Gould convinced Darwin all the finches were closely related and differed anatomically, especially in their beaks - only because of their different diets, on the different islands.

Darwin was later compelled to write in his Journal of Researches:

"Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends."

As Darwin then came to examine more of his Beagle records from his new viewpoint, he realized he'd been blinded by the creationist codswallop. After reading Thomas Malthus' An Essay on the Principle of Population, Darwin realized that in the ongoing struggle for scarce resources, slight variations of beneficial nature would tend to be naturally selected - leading to increased survival and hence increase in adaptive traits.

Thus, a finch peculiar to one island lacking in fruits, or other normal finch fare, could survive if it simply increased its adaptive repertoire - say by eating insects instead.

Thanks to Darwin, going with his re-evaluated observations (in the light of John Gould's taxonomic inputs and insight) we had a genuine scientific theory to account for species' origins. The beauty of the theory of Evolution, inhered in its being powerful and all encompassing - explaining everything from the telomeric fusion of the ape chromosomes 2p and 2q (to become the 2) in humans, to the fact that chimps and humans have the exact same cytochrome -c protein sequence - impossible were it not for common origin. More to the point, the theory of Evolution was fully testable based on science, and not religious fiats, dictates or antiquated bibles written hundreds of years ago and corrupted over time with re-translations and mistranslations.

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