Thursday, May 07, 2009

Casey Luskin Writes About the Universal Common Ancestor

Casey Luskin is writing about the tree of life and the universal common ancestor. The second installment in a series of five posting is here.
When speaking to the public, evolutionists are infamous for overstating the evidence for universal common ancestry. For example, when speaking before the Texas State Board of Education in January, 2009, University of Texas evolutionist biologist David Hillis cited himself as one of the “world’s leading experts on the tree of life” and later told the Board that there is “overwhelming agreement correspondence as you go from protein to protein, DNA sequence to DNA sequence” when reconstructing evolutionary history using biological molecules. But this is not accurate. Indeed, in the technical scientific literature, one finds a vast swath of scientific papers that have found contradictions, inconsistencies, and flat out failures of the molecular data to provide a clear picture of phylogenetic history and common descent.

Indeed, the cover story of the journal New Scientist, published on the very day that Dr. Hillis testified, was titled, “Why Darwin was wrong about the tree of life.” Directly contradicting Hillis’ gross oversimplification of molecular systematics, the article reported that “The problem was that different genes told contradictory evolutionary stories.” The article observed that with the sequencing of the genes and proteins of various living organisms, the tree of life fell apart:
It's true that things are very confusing at the base of the tree of life. The evidence indicates that genes were frequently exchanged between primitive prokaryotic species and this means there is no single tree that represents all of life.

But this doesn't negate the idea of a universal common ancestor. The origin of life could still be a unique event that gave rise over millions of years to many different descendants that subsequently exchanged genes. Or, there may have been a few independent origins of life.

The available evidence shows that most fundamental properties of life are shared by all living things (e.g. basic metabolic pathways, genetic code). This is consistent with a unique origin of life but it's also consistent with multiple origins as long as only one version of each process has survived. The odds favor a single origin and a universal common ancestor.

What's interesting about Luskin's article is that he is hopelessly confused about the difference between a phylogenetic tree and the origin or life. He seems to think that a bushy tree with many interconnecting branches rules out a universal common ancestor. I don't know what he postulates in its place unless the idea of God creating three or four different primitive prokaryotes is what appeals to him more than God just doing it once.

Intelligent Design Creationists come in many different flavors. Often it's hard to decide whether they are being deceptive (lying) or just ignorant. I think that Casey Luskin is just ignorant. He finds it difficult to make a coherent argument and he doesn't take the time to learn more about his subject. In that sense, he's much less dangerous than Jonathan Wells.


  1. "Often it's hard to decide whether they are being deceptive (lying) or just ignorant."

    Or both. I would argue that Luskin is both ignorant and a liar in that he is aware of his ignorance but misrepresents himself as knowledgeable. I agree that a liar like Wells is much more dangerous.

  2. No, I addressed this point specifically in the Q&A when Caseytits and John 'I love Nazis' West came to town.

    The only excuse for continually being 'confused' on this issue is that they are liars.

  3. Casey is a paid liar and a credulous fool. He is, however, a useful tool for the frauds at the Disco Toot. He has an ability to bamboozle the brain-dead creationists with his sciencey sounding bullshit.

  4. I find it ironic that Luskin, a lawyer with a BS in geology, would imply that Hillis, who really IS a leading expert on these issues, was embellishing his importance.

    This from a guy associated with a group of people who have made credential embellishment a fine art - The Isaac Newton of Information Theory?

    Give me a break...

  5. I sometimes think that a fundamental trait of fundamentalists is "I must be able to lie to myself convincingly; once I can do this, lying to everyone else is just more of the same".

    (Echoes Feynman's point about honesty in his Cargo Cult lecture, for those who know it.)

  6. Exchange of genes between primitive prokaryotes means that toward the base it is not strictly a "tree" in the mathematical sense (it's a more general graph), but that doesn't mean that the general description of the whole structure as a tree is particularly misleading as a first approximation, nor does it make a common ancestor a nonsense.

    It's no more ridiculous to refer to the tree of life than it is to discuss Newton's laws. For most present purposes, it's an extremely accurate and useful description.

  7. I think there is a principle behind a lot of anti-evolutionary propaganda organizations (the DI or various church groups) that telling a 'white lie' is OK in order to protect the greater good. It's like telling your kid not to stray into the woods because the big bad wolf is there (when you know there are no wolves in that forest but want to make sure they don't just wander off and get lost). Obscuring the fact that there are lots of data supporting the scientific consensus model of evolution is seen as acceptable by many. Its rare that they are ever publicly confronted on this tactic as it is something that is directly contrary to science.