A few weeks ago my email box was full of gloating messages from creationists claiming that the latest discovery of complex eyes in the Cambrian “proved” creationism and “refuted” evolution. As usual, creationists demonstrate a remarkable ability to completely misunderstand and misinterpret real science, and get the message of the paper ass-backward. The article to which they referred is an excellent new paper on the appearance in the Early Cambrian of compound eyes, slightly earlier than they were known previously. But creationists doesn’t know enough science to understand the paper—all they do is read “complex eyes” and “Early Cambrian” in the title, and to them, “Darwinism is falsified.” It never ceases to amaze me how they can mangle legitimate research to mean just the opposite of what was written, but so strong are their belief filters that they hear only what they want to hear, and completely miss the point of most of the world of science that doesn’t fit their preconceived notions.
The discovery itself is quite remarkable, and good discussions are given here and here. From the Lower Cambrian Emu Bay Shale of Kangaroo Island, South Australia, are nicely preserved elements (ommatidia) of compound eyes, which are larger and more complex than any others known from the Early Cambrian (although similarly complex but smaller compound eyes are found in trilobites of the Atdabanian Stage of the Cambrian, just a few million years later). The eyes themselves are individual molts and not attached to bodies, but they were once part of some large arthropod. Some ommatidia have over 3000 lenses, equal to many of the compound eyes found since the Cambrian. Although it forces us to revise our treatment of the history of eyes a bit, it it not “the end of Darwinism” as creationists claim. The molecular data have long predicted that complex compound eyes should have appeared long before we see them in the fossil record, but were simply not preserved because they had no hard parts yet (probably because conditions in the Precambrian and Early Cambrian oceans only gradually reached a threshold that allowed mineralization of soft tissues). This discovery simply extends the range of compound eyes back a few million years earlier than we had known previously.
Yet if you read the creationist accounts of this discovery, it was as if this one paper had caused all of evolutionary biology to crumble! The main thread of their argument is the same, tired old “Cambrian explosion” misconception they’ve been beating for decades. Somehow, the appearance of one more complex fossil in the Early Cambrian makes the “Cambrian explosion” completely inexplicable by evolution. In the words of creationist IDiot David Buckna, “The Cambrian explosion is affirmed; complexity appears suddenly without transitions; Darwinism is falsified; the inference to the best explanation is intelligent design. Let the world know.”
That is pure garbage, and shows once again that creationists cannot read, or if they do read, they don’t understand anything. The truth of the matter was outlined in Chapter 7 of my 2007 book Evolution: What the Fossils Say and Why it Matters, and I will summarize the major points below:
1. Contrary to creationist lies, there is an excellent sequence of fossils that show the logical stepwise transition from the earliest single-celled bacteria at 3.5 billion years ago, to the first eukaryotic cell at 1.8 billion years ago, to the multicellular (but soft-bodied) Ediacara biota 610 million years ago, and finally in the first two stages of the Cambrian (545-520 million years ago), the “little shellies”, which are small bit of armor of the first skeletonized organisms. Only in the third stage of the Cambrian (the Atdabanian) do the hard-shelled trilobites and other complex organisms first appear. This is exactly as would be predicted by evolution: single-celled prokaryotes, then eukaryotes, then soft-bodied multicellular creatures, then the first tiny bits of skeletonization, and finally large skeletonized fossils.
When I read the creationist versions of this reality, they always ignore all the evidence of anything prior to trilobites, despite the fact that the Ediacara biota has been known for 70 years, and the rest documented over the past few decades. They act as if no fossils existed before the trilobites (as it was in Darwin’s day) and none of the discoveries of the past 70 years existed. When Michael Shermer and I debated and beat creationists Stephen Meyer and Richard Sternberg in Beverly Hills in 2009, I attacked them on this very point—and they dodged it by focusing on the trilobites, and completely ignoring all the less complex organisms that preceded them.
2. The term “Cambrian explosion” is a complete misnomer. These events took place between 610 and 520 million years ago (spanning 90 million years), or even if you just restrict it to the Early Cambrian, 25 million years. Ninety million or even 25 million years is hardly a rapid “explosion” by any stretch of the imagination. I’ve urged geologists to use the more appropriate “Cambrian slow fuse” to reflect reality and not give the creationists fuel for their lies, but it’s hard to change old habits. The archaic term “Cambrian explosion” dates back to the early days of geology, when the events of the Precambrian-Cambrian transition, lasting 25 to 90 million years, seemed abrupt on the scale of the 520 million years that followed, or the 3 billion years that preceded it. That’s a geologist’s perspective, where millions of years are nothing when you’re used to billions of years of time.
Whatever caused the “Cambrian slow fuse”, and however it occurred, is is most certainly not an “abrupt explosion” that is too fast for evolution to explain. Even 25 million years is almost half of the Cenozoic, or the “Age of Mammals” that we are still a part of! There is plenty of time for events to unfold at normal rates of evolution, and the discovery of earlier compound eye fossils does not change the overall pattern.
Ironically, the creationists themselves cite articles showing the “Cambrian explosion” took tens of millions of years (clearly labeled through the paper) yet they don’t believe in a time scale longer than 6000 years for all of creation! That’s their usual tactic: cherry-pick a few things out of context, quote-mine whatever seems to support their position, and then ignore everything else that completely contradicts and falsifies what they have asserted. That may serve their purposes, but it’s not science and it’s dishonest. But as I documented in my 2007 Evolution book, they don’t care about honesty as long as they can distort and misquote science and scientists to serve their purposes of evangelism and suppression of science they don’t like.
I realize that most of us are tired of creationist lies and propaganda and political interference, and want to get on with our lives doing science and true scholarship, or just earning a living. But garbage like this latest event are evidence that the fight must go on. We must keep vigilant that they don’t threaten our schools or scientific institutions any more than they do already.