Weekly Random Ten (17 November 2005)
Science Against Evolution Edition
A friend of mine sent me a link to this site -- the official site of Science Against Evolution. I haven't toured the whole place yet, but it seems like an amalgamation of misinformation and common creationist canards.
Science Against Evolution is a California Public Benefit Corporation whose objective is to make the general public aware that the theory of evolution is not consistent with physical evidence and is no longer a respectable theory describing the origin of life.Ha! Public benefit!? Ask the folks in Dover about the public benefit of violating the establishment clause. Guess what? The theory of evolution does not describe the origin of life, never did describe the origin of life, never will describe the origin of life, and never intends to describe the origin of life. The theory of evolution deals with changes in life on earth since the origin of life -- as Darwin so famously put it, "the origin of species".
They even have an entire page dedicated to "The Failure of Genetics" written in 1998 dealing with this review from Science. If you don't have access, this short review deals with how long external branches and short internal branches lead to incorrect phylogenies when using 18s RNA to determine the relationships of all animals. I'm not as committed to debunking individual creationist lies as some people, and boy is this page loaded with them, but I'll point out a few things.
It took me a while to figure out what they mean by "correlation". It turns out that the review has a figure showing bootstrap support of the nodes. Bootstrap values are calculated by randomly sampling the data (with replacement) to come up with a new data set and seeing if the results based on that new data set is consistent with those based on the original data. If you repeat this process multiple times and keep track of how many runs are consistent, you can get the bootstrap support for your data. This has nothing to do with correlation.
The article then discusses a figure that shows that mollusks are more closely related to deuterostomes than arthropods when the creatures being compared are a scallop (a mollosk), a sea urchin (a deuterostome), and a brine shrimp (an arthropod). That isn't too surprising. Intuitively, a scallop seems more like a sea urchin than a shrimp, and the 82% correlation between the scallop and sea urchin shown on their diagram isn't surprising.
But when a tarantula is used as the representative of the arthropod, there is a 92% correlation between the scallop and the tarantula. It doesn't seem reasonable that a scallop should be more closely related to a harry [sic], land-dwelling spider than to a sea urchin.
And the reason for doing molecular systematics is to overcome our subjective interpretation of phenotypic characters. It doesn't matter what something looks like upon first glance, because convergent evolution can lead to similar appearances despite different origins. You really need to take a much closer look to determine if the characters are homologous. This is so obvious my students look at me like I'm a moron when I tell them it in introductory biology.
If we ignore the author's absolute ignorance regarding simple statistical methods, we can focus on the total misinterpretation of the Science review.
Since the authors are evolutionists, it never occurs to them that the data doesn't agree with the assumed evolutionary relationship because the theory of evolution is wrong. They fall back to the old "evolution happened so fast we must have missed it" argument. They assume a "rapid divergence of most of the animal phyla" that caused not only missing link fossils, but also missing link RNA sequences.The assumed evolutionary relationship is based on evidence -- assumptions made in scientific models tend to be based on previous studies. The inconsistencies in the trees can be attributed to a describable phenomenon: long branch attraction. If multiple taxa diverge in a short amount of evolutionary time, reassembling the order of divergence will be extremely difficult. This problem can be overcome with better taxanomic sampling. For example, if you add some intermediate relatives for each of the taxa (ie, chordates for the echinoderms), you can remedy the problem of convergent evolution in the rRNA sequences.
Another problem with rRNA is that there is epistatic selection operating to maintain the secondary structure of the molecule so the sights are not independent. To overcome this problem, you can construct trees with amino acid sequences. Ok, I'm sick of this shit . . .
Creationists suck! Here's this week's evolgen Random Ten:
- Tiger Army - Outlaw Heart
- Jimmy Cliff - Sitting in Limbo
- No Use For A Name - On the Outside
- Me First and the Gimme Gimmes - It's Raining on Prom Night
- Teen Idols - Lovely Day
- 311 - What Was I Thinking
- Mad Caddies - Booze Cruise
- The Von Bondies - Poison Ivy
- Redman - I'll Bee Dat!
- Hot Hot Heat - Ladies and Gentleman