All That We Know About Evolution Is Wrong
Each New Discovery Changes Everything
I’m not happy with the way that headline writers try to attract attention. My dad once told me that advertisers purposely misspelled words in order to grab attention to their pitch, and I sometimes wonder whether headline writers don’t do something similar. “New Discovery Overturns Evolution.” It grabs hopeful creationists, eager to see that William Dembski has been finally vindicated in his predictions that we are in the sunset years of a Darwinist Paradigm that prevents us from truly understanding how evolution works. So they click and learn that, for example, Ardipithecus ramidus’ new revelation is not a time-stamp with Mr. Deity’s name on it. What we learned from the teams investigating the remains was instead, while extremely exciting for human anthropologists, the rather mundane and archaic knowledge that “Ardi’s” clasping foot indicates something about our common ancestry with chimps and that chimpanzees acquired this trait long after the Great Branch-Off between Man and Pan.
It is new, and it is cool stuff, but this isn’t the sort of discovery that will lead to the wholesale dumping of copies of The Descent of Man into the trash bin of history. It is a new piece to a giant jigsaw puzzle of the course of human evolution from the earliest protozoan through the mini-mammals surviving the K-T boundary, up to the Cro-Magnons who are reading and typing on the internet. It’s quite likely that the pieces we have put together so far are in the wrong places in the picture that the puzzle represents, and that is why paleoanthropologists do what they do.
“All that we know about evolution is wrong” is a close approximation to the truth but not an absolute. That’s the thing about the process of discovery, and methodologies are continually refined and adjusted, tweaked and teased in order to dig out a bit more data from tenuous strands of DNA and crumbling bones not yet fossilized. It takes an agonizingly long time for a body to turn to stone, and when you consider how rare an event it is for a dead animal or a plant to turn into a solid piece of rock through mineral replacement under ideal conditions you can see how difficult the task of the extraction of our history becomes. John Hawks’ quote from Tim White’s paper1 explains the dangers of haste:
The bony remains of this individual (ARA-VP-6/500) (Fig. 3) (37) are off-white in color and very poorly fossilized. Smaller elements (hand and foot bones and teeth) are mostly undistorted, but all larger limb bones are variably crushed. In the field, the fossils were so soft that they would crumble when touched. They were rescued as follows: Exposure by dental pick, bamboo,and porcupine quill probe was followed by in situ consolidation. We dampened the encasing sediment to prevent desiccation and further disintegration of the fossils during excavation. Each of the subspecimens required multiple coats of consolidant, followed by extraction in plaster and aluminum foil jackets, then additional consolidant before transport to Addis Ababa.
Okay, yeah, I don’t understand all of what is being written about in this quote. I do know that paleoanthropologists can’t just grab the bones and transport them to California for study. They have to tease away the setting carefully so as not to further the damage already done by water, wind and crushing weight. The extraction was completed fifteen years ago and aided by technologies such as CT scanning.
The anthropologists at the time of Darwin’s writings on The Descent of Man didn’t have access to such tools and methodologies, so it should hardly be news nor even a surprise that our murky evolutionary puzzle is being changed from what was written by 19th-century geologists and students of evolution. What they observed was seen through a glass much darker than the glass current scientists use, but they were very well on their way nonetheless to shaking ancient notions of human evolution. They were shedding the idea of the Great Chain of Being from bacterium to man and presenting evidence that we really are not so elevated in nature as once was taught.
The nineteenth century was one of the most amazing eras in human discovery yet undertaken, because those methodical explorers hammering away in quarries to find and classify “terrible lizards,” gathering and cataloging rocks and fossils, comparing and contrasting anatomical features from stone to modern skeletons and trying to decipher how humans came about, well, they broke the old picture that illustrated that we are in fact a separate and special creation. They taught us that we are a part of nature and not separate from it. Unfortunately, breaking the old picture necessitated the assembly of a new one. We still only have a few soggy and worn pieces and are trying to fit them in place without a complete guide.
DNA and genomics aid in our project to discover who we are and where we come from (and where we are going). Incompletely fossilized and mineralized bones of ancestors (or non-ancestors as in the case of Ardipithecus) will show us where we have been right and where we have been wrong.
So, all that we now know about human evolution is quite possibly wrong. But that is what is so exciting about Ardi. Fifteen papers were simultaneously released on what has been learned so far from the discovery. From those papers will come new questions about humans and our friends the chimps and bonobos. When did they start climbing trees? Why did they return to trees while we became ground-walkers?
The focus of the Intelligent Design movement within creationism has been to pick up the discarded pieces which don’t work, those which never really fit but were inserted in deference to religion. It’s a set of pieces with god-shaped prongs and slots. When William Paley used them, they made sense in the context of natural theology. Following Mary Anning’s, Charles Darwin’s, William Buckland’s, Alfred Russell Wallace’s, Richard Owen’s and Gideon Mantell’s discoveries, those pieces no longer were needed to explain what the creationists want anthropology to do. The creationists can’t admit that the pieces are completely extraneous. The pieces that they want scientists to go back to using don’t answer the questions that anthropologists are asking and answering. The process is painstaking and yet rewarding.
How much of the differences between human brains and chimp brains can be accounted for by the selective pressure of cooked versus raw meat? Which genes are responsible for the differences in the way our hands work versus the way their hands work? Is it a simple matter of regulatory genes controlling development in different ways to develop muscles in chimps which emphasize upper body strength while we develop with a stronger emphasis on lower body strength?
Our past is in our future. While the fact that we are the products of evolution is not in question, how we came to what we are is still being discerned. While evolution will not be overturned, all that we now know about how may one day be proved wrong. While the headline writers at Yahoo News may have been trying to improve click-rate, they were “write” for all the wrong reasons.
- White TD, Asfaw B, Beyene Y, Haile-Selassie Y, Lovejoy CO, Suwa G, WoldeGabriel G. 2009b. Ardipithecus ramidus and the paleobiology of early hominids. Science 326:75–86. [↩]
This entry was posted on Monday, October 5th, 2009 at 6:38 am and is filed under Mike Haubrich, Science. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.