Evolution by Loss
Evolutionists have added a counter-intuitive notion to their explanatory toolkit. It surfaced this week in Nature,1 then reverberated around the media: our ancestors became human when they lost genetic information from ape-like ancestors.
New Scientist exemplified the new story line: “Key to humanity is in missing DNA.” Reporter Andy Coghlan explained the central idea:
The key changes are not in bits of DNA that humans acquired as they evolved – extra genes that we have but chimps and other animals do not – but in chunks of DNA that we lost. What’s more, the chunks in question are not even genes at all, but sequences of DNA that lie in between genes and act as switches, orchestrating when and where specific genes are turned on and off through the course of an animal’s development.
While popular reporters (e.g., Live Science, National Geographic) are swapping punch lines about a more prurient aspect of the story (the loss of stiff structures from a particular part of the male anatomy), the real punch line is the notion that the descent of man really was that – a descent of genetic information. Zoe Corbyn wrote for Nature News, “The approach differs from that in most studies … in looking at what has been deleted from the human genome rather than what is present.”
The researchers identified 510 genetic regions present in chimpanzees but missing in humans. Only two of these have been tested so far for function. The original paper mentioned loss of information a dozen times, but gain of information only once – and that just as a possibility: “Deletions of tissue-specific enhancers may thus accompany both loss and gain traits [sic] in the human lineage, and provide specific examples of the kinds of regulatory alterations.” One of the losses affected male anatomy; the authors explained this as having something to do with the evolution of monogamy, though it is unclear whether that would be a cause or effect, even in evolutionary terms. In National Geographic, Rhonda Snook, a specialist in sexual anatomy, said, “theories linking simpler genitalia to monogamy are still tenuous.”
The other genetic loss involves the brain: the removal of a factor ostensibly limiting brain size. According to the authors and reporters, this somehow led to the expansion of the human brain, instead of a tumor, and by implication, our intelligence and rationality. That idea would appear to only make sense if brain structure and function were already pregnant with intellectual and rational possibilities. In that case, why would a factor evolve to restrict expression of such a valuable asset in lower primates?
“We think losing highly specific enhancer regions is one of the mechanisms that has contributed to the evolution of human traits,” said David Kingsley (Stanford), a co-author of the study, as quoted in New Scientist. Apparently other evolutionists think this is a wonderful new story line:
“Hats off to them,” says Ewen Birney of Cambridge University. “It has long been thought that evolution would work by deleting as well as creating things, and it has long been thought that the bulk of human evolution occurs in regulatory information,” he says. “However, this is a real example of both of these things being shown to be true rather than people simply making arguments for them.”
Svante P??bo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and a lead researcher into the genetic differences between humans and their close relatives, including chimps and Neanderthals, says the new work is “a beautiful study”. “I’m sure several groups will now study the role of the gene involved in brain cortex formation very carefully,” he says. “I’m hopeful that the other elements in their list of almost 500 conserved features lost in the human genome will turn out to be interesting too.” Watch this space.
1. McLean, Reno, … Bejarano, Kingsley et al, “Human-specific loss of regulatory DNA and the evolution of human-specific traits,” Nature 471 (10 March 2011), pp. 216?219, doi:10.1038/nature09774.
Here is the new story of evolution:
Once upon a time, because Stuff Happens, a cell emerged that had all the potential of every living thing. Evolution, the goddess of Nature, began whittling down that potential in the Great Ancestor, producing, as original information was left on the cutting room floor, trilobites, sharks, giant sequoias, butterflies, sea tortoises, tyrannosaurs, eagles, petunias, blue whales, mice, dogs, and chimpanzees. Last and least, humans emerged with the leftovers.
Darwin must be moaning in [insert eternal destination]. In this twist on his theory story, you are not even as highly evolved as a mouse. From the slightest bit of data, whole worldviews have been given credence by philosophically-challenged academics and an inebriated press with the moral propriety of middle school boys. Try this notion on your term paper, car, software, or retirement plan: see what you create by removing parts.
“Watch this space,” Coghlan ended his tale. We adapt an observation from our 08/19/2004 commentary:
Interesting ending: “Watch this space.” This implies that there is nothing to watch except space: i.e., emptiness, a void, a vacuum. If, after 151 years of speculation about human evolution, the evolutionary story has left nothing but a space, asking us to watch it as if something important is about to happen sounds like an empty promise from a used Darwinmobile salesman. Any takers?
Another space to watch is the contents of the evolutionists’ skulls. It’s easier to do now because Birney just took their hats off. They, too, display emptiness, a void, a vacuum, their contents having been sacrificed on the altar of the Bearded Buddha (cartoon).