I may be a bit late to the party, but I’ve finally gotten a chance to read Stephen Meyer’s latest book, Darwin’s Doubt. Having read his previous book, Signature in the Cell, I had high expectations, and Meyer did not disappoint. Darwin’s Doubt takes a look at the longstanding enigma of the Cambrian explosion – a very brief time in history in which the majority of all major animal forms abruptly appear in the fossil record with no trace of simpler ancestral forms. Darwin recognized the problem the Cambrian fossils posed to his theory, but thought future discoveries would solve the problem. After 150 years, the problem hasn’t been solved. Instead, it’s been made more acute.
Scientists are increasingly coming to recognize that Darwin’s theory cannot explain the Cambrian explosion. Some are proposing alternative, naturalistic explanations. Others see the Cambrian explosion as powerful evidence for the intervention of an Intelligent Designer nearly 550 million years ago. Who’s right? Darwin? The Darwin doubters? Intelligent Design theorists? Stephen Meyer walks the reader through the evidence, and then evaluates competing explanations to see how they stack up against the evidence. It should be no surprise to those who know Stephen Meyer where the book concludes. The question is how he gets to his conclusion.
What follows is a roughly chapter-by-chapter summary of Meyer’s argument that I will post over the course of several days. It does not do the book justice, but it’s a start. Read my summary, and then buy the book. Even if you don’t agree with Intelligent Design, Darwin’s Doubt will help you better understand what needs to be explained, the current state of the field, and the latest discoveries in paleontology and developmental biology. Meyer is a master storyteller and great at making difficult scientific ideas easy to digest.
Chapters 1-2
Though Darwin offered a very compelling and systematic argument for unguided, macroscopic biological change over time, one piece of evidence in particular did not gel well with his theory – the fossil record contained in the Pre-Cambrian and Cambrian strata – and paleontologists were not shy about pointing that out. The Cambrian period began 544 MYA (million years ago). An explosion of animal life appears in the record starting 530 MYA and lasts 10 MY, with the largest explosion of animal phyla occurring in the first 5-6 MY (which is just 1/10 of 1% of the earth’s history). During this 5-6 MY period, at least 16 phyla and 30 classes of animals make their first appearance. Strangely, we find no ancestors to this vast array of organisms in the Pre-Cambrian strata.
Darwin acknowledged that the early fossil evidence did not support his theory, but thought the problem was that ancestors to the Cambrian animals and the intermediate forms that followed were either not preserved, or just not found yet (“artifact hypothesis”).
The discovery of the Burgess Shale in 1909 did not help Darwin’s case, but offered further evidence against it. Many more Cambrian animals were discovered (with no Pre-Cambrian ancestors), further illuminating just how diverse and complex the Cambrian animals were. The pattern of the fossil record was shown to be the exact opposite of what we would expect to find if Darwin’s theory was true. If change comes about through descent with modification from a common ancestor, with small changes adding up into bigger changes over time, we should expect the number of phyla in the Cambrian to be relatively few, with more and more phyla being added over time. Instead, almost all known phyla appear in the Cambrian. Some of those phyla have died out over the years, and a couple have appeared since then, but the majority of all phyla are present at the base of the tree, not the top, and those Cambrian phyla show no evidence of ancestors. Instead of seeing an exponential increase of new phyla over the last 500 MY, we simply see the diversification of the Cambrian phyla into more and more distinct examples of that phyla. So Darwin’s depiction of the tree of life is exactly the opposite of what we find in the fossil record. You might say it is upside down.
Jeffrey Schwartz (University of Pittsburgh) explains the predicament the Cambrian explosion puts Darwinists in: “We are still in the dark about the origin of most major groups of organisms. They appear in the fossil record as Athena did from the head of Zeus – full-blown and raring to go, in contradiction to Darwin’s depiction of evolution as resulting from the gradual accumulation of countless infinitesimally minute variations.”[1]
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[1]Jeffrey Schwartz, Sudden Origins: Fossils, Genes, and the Emergence of Species (New York, Wiley, 1999), 3, as quoted in Meyer, 318.
Thinking to Believe 
December 2, 2014 at 1:58 pm
Hello Jason; where’ev you been? I’ve been doing my darndest trying to keep your posts lively without your fodder feeder.
Darwin was right when he wrote about what he “did not know” so of course speculation continues to abound by “creationists” consistent with their “Absolute Certainty” mindset. Darwin wrote, “the difficulty of assigning any good reason for the absence of vast piles of strata rich in fossils beneath the Cambrian system is very great,” yet he expressed hope that such fossils would be found, noting that “only a small portion of the world is known with accuracy.”
Quick Question would the lava being spewed from the earth since its formation contain any fossil records in the melted rocks from the decending earth crust pushes down to the core in the volcanic cycle? I don’t think so.
A very brief time in history in which the majority of all major animal forms abruptly appear in the fossil record is over a 40 million year period. 40 millins years is a long time to grow old.
Molecular oxygen was not present as a significant fraction of Earth’s atmosphere until after photosynthetic life forms evolved and began to produce it in large quantities as a byproduct of their metabolism. This radical shift from an inert to an oxidizing atmosphere caused an ecological crisis sometimes called the oxygen catastrophe. At first, oxygen would quickly combine with other elements in Earth’s crust, primarily iron, as it was produced. After the supply of oxidizable surfaces ran out, oxygen began to accumulate in the atmosphere, and the modern high-oxygen atmosphere developed. Evidence for this lies in older rocks that contain massive banded iron formations, laid down as iron and oxygen first combined.
Life
What was life like 560 million years ago? Bacteria and green algae were common in the seas, as were the enigmatic acritarchs, planktonic single-celled algae of uncertain affinity. But the Ediacaran also marks the first appearance of a group of large fossils collectively known as the “Ediacara biota.”
The question of what these fossils are is still not settled to everyone’s satisfaction; at various times they have been considered algae, lichens, giant protozoans, or even a separate kingdom of life unrelated to anything living today. Some of these fossils are simple blobs that are hard to interpret and could represent almost anything. Some are most like cnidarians, worms, or soft-bodied relatives of the arthropods. Others are less easy to interpret and may belong to extinct phyla. But besides the fossils of soft bodies, Ediacaran rocks contain trace fossils, probably made by wormlike animals slithering over mud. The Ediacaran rocks thus give us a good look at the first animals to live on Earth.
The Ediacaran is the youngest period of three that make up the Neoproterozoic Era, which in turn is the youngest of three eras within the Proterozoic Eon. The Ediacaran is sandwiched between the older Cryogenian Period and the younger Cambrian Period.
When Charles Darwin wrote On the Origin of Species, he and most paleontologists believed that the oldest animal fossils were the trilobites and brachiopods of the Cambrian Period, now known to be about 540 million years old. Many paleontologists believed that simpler forms of life must have existed before this but that they left no fossils. A few believed that the Cambrian fossils represented the moment of God’s creation of animals, or the first deposits laid down by the biblical flood. Darwin wrote, “the difficulty of assigning any good reason for the absence of vast piles of strata rich in fossils beneath the Cambrian system is very great,” yet he expressed hope that such fossils would be found, noting that “only a small portion of the world is known with accuracy.”
Since Darwin’s time, the fossil history of life on Earth has been pushed back to 3.5 billion years before the present. Most of these fossils are microscopic bacteria and algae. However, in the latest Proterozoic — a time period now called the Ediacaran, or the Vendian, and lasting from about 635 to 542 million years ago* — macroscopic fossils of soft-bodied organisms can be found, confirming Darwin’s expectations.
Stratigraphy
The Ediacaran is the youngest period of three that make up the Neoproterozoic Era, which in turn is the youngest of three eras within the Proterozoic Eon. The Ediacaran is sandwiched between the older Cryogenian Period and the younger Cambrian Period.
Many paleontologists held little hope that fossils would ever be found in rocks so ancient as the Ediacaran. It is now known that rock layers may be deeply buried, twisted, folded and melted by geologic forces. It is easy to see that such changes to rock would destroy any fossils that might otherwise have been preserved. Older layers of rock, which have been around for a longer time, are more likely to have undergone such changes, and are thus less likely to preserve fossils. With no known fossils from the Ediacaran little more could be said, but in the late 1900s macroscopic fossils of soft-bodied animals, algae, and fossil bacteria were found in these older rocks in a few localities around the world. With the discovery of these earliest fossils came a surge of interest in the Ediacaran and the Proterozoic Era that continues today.
The first mineralized fossils appear after the Ediacaran, but before Cambrian begins at around 580 – 590 my; they comprise ambiguous parts, possibly denticles and plates and tubes of unknown affinity and putative calcareous algae. Many of the genes and the proteins they encode are found to be conserved across geologic time from the Precambrian, especially those involved in the most basic cellular functions
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December 3, 2014 at 3:23 am
Fossil evidence supports the origins of life on earth earlier than 3.5 billion years ago. The North Pole microfossils from Australia (the Apex Chert) are complex enough that more primitive cells must have existed earlier. From rocks of the Ishua Super Group in Greenland come possibly the earliest cells, as much as 3.8 billion years old. The oldest known rocks on Earth are 3.96 billion years old and are from Arctic Canada. Thus, life appears to have begun soon after the cooling of the Earth and formation of the atmosphere and oceans.
These ancient fossils occur in marine rocks, such as limestones and sandstones, that formed in ancient oceans. The organisms living today that are most similar to ancient life forms are the archaebacteria. This group is today restricted to marginal environments. Recent discoveries of bacteria at mid-ocean ridges add yet another possible origin for life: at these mid-ocean geological structures where heat and molten rock rise to the Earth’s surface.
The Proterozoic Eon covers the time span from 2.5 billion to 544 million years ago. Simple, prokaryotic cells still dominated the world’s environments until the evolution of simple eukaryotes approximately 1.5-1.2 billion years ago. With the appearance of eukaryotes comes the development of sexual reproduction, which greatly increased the variation that natural selection could operate on. A major environmental change, initiated by living things, was the development of oxygenic photosynthesis. This led to increasing oxygen levels during later Proterozoic. Geologists refer to the “great iron crisis” when the rising levels of oxygen in the world’s oceans caused the formation or iron oxide (Fe2O3), often preserved as the banded iron formation (an important commercial source of iron).
Source, with photos, last mofified May 18, 2010:
http://www2.estrellamountain.edu/faculty/farabee/BIOBK/biobookpaleo2.html
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December 3, 2014 at 3:28 am
Where did life originate and how?
EXTRA TERRESTIAL: In 1969, a meteorite (left-over bits from the origin of the solar system) landed near Allende, Mexico. The Allende Meteorite (and others of its sort) have been analyzed and found to contain amino acids, the building blocks of proteins, one of the four organic molecule groups basic to all life. The idea of panspermia hypothesized that life originated out in space and came to earth inside a meteorite. Recently, this idea has been revived as Cosmic Ancestry. The amino acids recovered from meteorites are in a group known as exotics: they do not occur in the chemical systems of living things. The ET theory is now not considered by most scientists to be correct, although the August 1996 discovery of the Martian meteorite and its possible fossils have revived thought of life elsewhere in the Solar System.
SUPERNATURAL: Since science is an attempt to measure and study the natural world, this theory is outside science (at least our current understanding of science). Science classes deal with science, and this idea is in the category of not-science.
ORGANIC CHEMICAL EVOLUTIN: Until the mid-1800’s scientists thought organic chemicals (those with a C-C skeleton) could only form by the actions of living things. A French scientist heated crystals of a mineral (a mineral is by definition inorganic), and discovered that they formed urea (an organic chemical) when they cooled. Russian scientist and academecian A.I. Oparin, in 1922, hypothesized that cellular life was preceeded by a period of chemical evolution. These chemicals, he argued, must have arisen spontaneously under conditions exisitng billions of years ago (and quite unlike current conditions).
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December 3, 2014 at 10:58 am
Fossils in relation to our modern economy:
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December 3, 2014 at 7:16 pm
Frank:
That is an amazing video revelation about OIL that could have any number of titles:
1. How Hoaxes begin,
2. The Bottom Line is $Bingo The Money God$
3. The Simplicity of Deceit
4. Belief has the World over a Barrel.
Great post…….
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