Wednesday 5 June 2013

More Headscratching Amongst Evolutionists


Darwin’s Doubt: An Interview with Stephen C. Meyer

Justin Taylor
May 30th, 2013



Dr. Stephen C. Meyer, author of Signature in the Cell: DNA and the Evidence for Intelligent Design and director of the Discovery Institute’s Center for Science and Culture, has a new book being published June 18 by HarperOne: Darwin’s Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design. 
(For the best discount and free shipping, you can pre-order the book here, and they’ll also send you four free eBooks on intelligent design.)

Dr. Meyer argues that the mysterious features of the Cambrian explosion are better explained by intelligent design than purely undirected evolutionary processes. He was kind enough to answer a few questions.

What is the “Cambrian Explosion”? 
The Cambrian explosion is an important event in the history of life where nearly all of the major animal body plans appear abruptly in the fossil record without any apparent evolutionary precursors.

Why is that significant?
What this means, in essence, is that virtually all of the major animal groups (called “phyla”)—vertebrates like fish, to arthropods (e.g., trilobites and shrimplike creatures), to various types of worms (e.g., earthworm-like annelid worms), to mollusks (e.g., shellfish), and many other types of animals—appear in a geological “blink of an eye,” without any direct ancestors in the fossil record. Even Richard Dawkins has observed that the Cambrian animals looked as if “they were just planted there without any evolutionary history.”


Do you believe it was a real event?
Yes, we take the Cambrian explosion to have been a real event. And we aren’t alone in taking that view. Most leading evolutionary paleontologists who are top authorities on the Cambrian period—people like Douglas Erwin, James Valentine, and Simon Conway Morris—agree that the evidence shows the Cambrian explosion was a real event, and is not merely an artifact of the fossil record.

Did Darwin know about the Cambrian explosion? Did he see problems with it?
Darwin himself knew that the abrupt appearance of animals in the ancient fossil record posed a problem for his theory. In his time, it was called the Silurian period, but later it was renamed the Cambrian.

Darwin knew that his theory of evolution by natural selection worked gradually, and required that structures and organs be built by “numerous, successive, slight modifications.”

But the Cambrian explosion contradicted that pattern, since it showed diverse and complex animal body plans appearing abruptly, without any fossil record of their evolution.

Darwin confessed that this was not something his theory could explain. He acknowledged that doubt in Origin of Species, and said it was a “valid argument against the views here entertained.”

Have the last century of fossil discoveries resolved or aggravated Darwin’s doubt?
Fossil discoveries since Darwin’s time have only made the Cambrian explosion problem worse for his theory.
Darwin believed that the fossil record was woefully incomplete, and he predicted that the problem of abrupt appearance of animals in the Cambrian would be alleviated by future discoveries.

But the opposite happened. Scientists have combed the Precambrian strata for the alleged precursors to the Cambrian animals, and they haven’t found the direct evolutionary ancestors that Darwinian theory predicts. Instead, they have made new discoveries which confirmed that the Cambrian explosion was real event—and a worldwide one—and that the animal phyla really did appear abruptly.

The first major Cambrian-era fossil discovery after Darwin’s time took place over a hundred years ago now, in 1909, when Charles Doolittle Walcott (then the head of the Smithsonian Institution) discovered the Burgess Shale Cambrian deposit in the Canadian Rockies. This deposit showed many diverse soft and hard-bodied organisms which were preserved in exquisite detail. They all appeared in the Cambrian, with no clear evolutionary ancestors.

The question remained, however, whether the Burgess Shale Cambrian animals were a lucky isolated event, or evidence of a worldwide pattern. Over the next decades, additional discoveries of Cambrian animals were made in other parts of the world, including Russia, Greenland, and Australia.

But the most spectacular find of all took place in 1984, with the discovery of Cambrian fossils in Chengjiang, China. This deposit confirmed that the Cambrian explosion was a worldwide event, with many of the same creatures found in Canada being present in beautiful detail.

So as more and more fossils have been discovered, we’ve found the same pattern over and over around the world: diverse types of animals appear abruptly in the Cambrian, without clear evolutionary precursors. This has accentuated the “dilemma” that Darwin faced.

How do you respond to the argument that humans can trace their evolutionary ancestry to the Cambrian fish since both share backbones and dorsal nerve cords?
Sure, humans and fish both share backbones and nerve codes. That’s no surprise to anyone. In fact, humans also share genes with bananas and bacteria. That organisms share genes or structural parts does not necessarily reflect common ancestry, because it could indicate that they were built upon a common body plan. After all, it’s a good design principle to re-use parts that work in different designs—this is exactly why mechanical engineers put wheels on both cars and airplanes, or why technology designers put keyboards on both computers and cell phones. That different organisms share some of the same parts could easily reflect common design rather than common descent.

In fact, when evolutionary biologists have tried to construct evolutionary trees (called “phylogenetic trees”) to show how the animal phyla are related, they have encountered great difficulties. An evolutionary tree based on one gene or body part, will sharply conflict with an evolutionary tree based upon another gene or body part. A paper just published in the journal Nature last week acknowledged that the genetic data has caused a lot of problems for those trying to construct a “tree of life.” One of the study’s co-authors, Antonis Rokas of Vanderbilt University, stated: “It has become common for top-notch studies to report genealogies that strongly contradict each other in where certain organisms sprang from, such as the place of sponges on the animal tree or of snails on the tree of mollusks.”



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