Slowing Down the Cambrian Explosion
“Although the cause of the Cambrian radiation is unknown,” states a story in Science Now, maybe it wasn’t as rapid as previously thought. Bruce Lieberman (U. of Kansas) is toying with the idea that trilobites, those icons of the Cambrian era, radiated into various ecological niches 65 million years earlier than the ~520 million year age generally accepted. If so, they would have had more time to evolve.
Lieberman compared physical features from 100 species of trilobites to determine their degree of relatedness. Then he teamed up with a geologist, Joseph Meert (U. of Florida), to infer from magnetic field orientations how long ago the southern supercontinent must have begun drifting toward the equator. Then he related the trilobite species to the continental fragments, and concluded that the continental breakup began 580 million years ago and was more gradual. “The analysis suggests that trilobites were already well-diversified by the time most researchers thought the Cambrian radiation began,” author Betsy Matson says.
This study was not motivated by a desire to know the truth about the unseen past, but to preserve evolutionary theory from one of its most damaging counter-evidences: the Cambrian explosion.
As Matson explains, “The traditional view of the Cambrian explosion is that life underwent an extraordinary, rapid diversification that resulted in the nearly simultaneous appearance of the ancestors for most major types of animals.” Simultaneous appearance is not evolution. Rapid diversification is not Darwinian gradualism. No wonder the Darwin Party reacts to the Cambrian fossil evidence in either of two ways: (1) sweep the problem under the rug, or (2) stretch out the explosion into slow motion. Problem is, an explosion is hard to hide, and a slow-motion explosion is still an explosion.
Lieberman relies on evolutionary assumptions to validate his evolutionary assumptions. (This, students, is called circular reasoning.) Lieberman assumes evolution occurred, and then uses that belief to teach us about how it occurred in spite of a critical piece of evidence that says it did not occur. Matson says, “Although the cause of the Cambrian radiation is unknown, many scientists suspect that the breakup of a southern supercontinent called Pannotia could have isolated populations and created new ecological niches that spurred rapid evolution.” Translated, this means that Darwin Party storytellers have a favorite plot that goes like this: the probability of a frog turning into a prince is low, but if you isolate groups of frogs, it happens faster. Giving the miracle a name like adaptive radiation does not make it empirical science (see 12/03/2003 entry).
You can draw any curve through two data points if the error bars are big enough. The error bars for adaptive radiation and for continental breakup and drift are huge. Lieberman merely assumed that rapid evolution would occur if he could get the “primitive” trilobite ancestors geographically isolated. By working with a Darwin Party co-conspirator to tweak the continental breakup dates, he got the continents to slow down by 500% to give his miracle more time. This is how the Darwinians can keep their story going despite any contrary evidence. No matter what, the show must go on.