Unintelligent argument

Surfing, I came across this blog by Rusty, whose “Evangelical Christian Blog (is) based on clear thinking and sound philosophy”. Okey dokey, what does it say? Well, in a section on how science plans to bar code the DNA of all life on Earth, there is this unintelligent design argument:

Let’s see, coding is applied to identifying items in a database. It’s quite interesting that a randomly generated, purposeless entity such as DNA could be utilized in such a manner.

Of course!  Bar-coding was designed, it applies to DNA and so DNA was designed. Or put it another way, goddidit.

Why can these people not learn the basics of what they wish to debunk? DNA did not develop “randomly”. The mutations may have been random, but the ones that survived did so by natural selection.

Glad to see there were several replies to Rusty’s post, pointing out his errors. Wasting their time with Rusty though, I would guess.

Comments

[ReSoT4eM]

I like your blog, even though I have a completely different worldview. A few of qustions:
You stated, " DNA did not develop “randomly”. The mutations may have been random, but the ones that survived did so by natural selection." Huh? Isn't natural selection itself a random process? If not, what is it? How did DNA develop by "natural selection" before it could replicate? Doesn't natural selection require reproduction? What's your definition of natural selection? Please clarify.

[Skeptico]

Thanks for your questions. Please see below.

Isn't natural selection itself a random process?  If not, what is it?

No, it’s not random: some outcomes are more likely to succeed than others. 

How did DNA develop by "natural selection" before it could replicate?

DNA was almost certainly always able to replicate - replication is one of its key features.  It seems likely that DNA was preceded by RNA, which can also replicate.  DNA is better than RNA at copying itself without errors, which is probably why DNA replaced RNA (by natural selection), although no one is certain.

Doesn't natural selection require reproduction?

Yes - reproduction being copying and replicating, at its most basic.

What's your definition of natural selection?

Wikipedia explains the process. Briefly, random mutations that make the gene more likely to reproduce will be selected. Mutations that prevent the gene from reproducing will obviously not be selected (will not replicate).

I’ll give you a simple example. You are in a jungle environment and a random mutation results in a creature that is all white. That animal can be seen easily by its predators and by its prey, and so is more likely to be killed, and/or less likely to catch food to eat, than if it wasn’t white. It is competing with similar animals that are better camouflaged. As it is less likely to live long enough to reproduce, its genes are less likely to be passed on. 

The same mutation in an animal living in a snowy environment will be at an advantage. Being all white, it is less likely to be seen by any predators, and less likely to be seen by its prey. It is therefore less likely to be killed, and better able to compete for food with its non-white brethren. It is therefore more likely to live long enough to reproduce, and stronger to fight off its competitors for mating when it does. The random mutation giving the white coat will therefore be more likely to be passed on to its offspring (will be selected).

You can see that the process is not random. The mutations more suitable to the environment will be passed on.

 

[ReSoT4eM]

More Questions:
You stated: "DNA was almost certainly always able to replicate - replication is one of its key features. It seems likely that DNA was preceded by RNA, which can also replicate."
Isn't that shifting the problem to RNA? How did the first RNA replicate? Are you saying that RNA appeared as a fully functioning replicating molecule?

You may be aware of this quote by renowned evolutionary biochemist Robert Shapiro in a published paper: "the evidence that is available at the present time does not support the idea that RNA, or an alternative replicator that uses the current set of RNA bases, was present at the start of life."
Shapiro is a skeptic who realizes the magnitude of the problem and is willing to admit it publicly. One of the main problems is that the D/RNA bases are very usntable, particularly (C) cytosine. That was the subject of the published article in which he made that quote.

There is reason for skepticism with regard to most of the origin of life theories. Perhaps you would enjoy his book (if you haven't already read it):
Origins: A Skeptic’s Guide to the Creation of Life in the Universe

[Skeptico]

You stated: "DNA was almost certainly always able to replicate - replication is one of its key features. It seems likely that DNA was preceded by RNA, which can also replicate."
Isn't that shifting the problem to RNA? How did the first RNA replicate? Are you saying that RNA appeared as a fully functioning replicating molecule?

No one knows for sure how RNA originally arose. But experiments do show that layered mineral deposits can attract, concentrate and link organic molecules, and that certain clays can act as “scaffolding” for assembling the molecular components of RNA – see Robert Hazen, “Life’s Rocky Start”, Scientific American April 2001.

The hypothesis goes that (1)neucleotides (sub units of RNA) link together to form RNA, then (2)RNA strands become housed inside a fatty acid membrane, that becomes like a cell (ie it could divide and grow). A clay, called montmorillonite, has been shown to do this. From my link, above:

In the 1990s biochemist James Ferris of Rensselaer Polytechnic Institute showed that montmorillonite can help create RNA. When he poured nucleotides onto the surface of the clay, the montmorillonite grabbed the compounds, and neighboring nucleotides fused together. Over time, as many as 50 nucleotides joined together spontaneously into a single RNA molecule. The RNA world might have been born in clay, Ferris argued, perhaps the clay that coated the ocean floor around hydrothermal vents.

“The thing that’s interesting is that there’s this one mineral that can get RNA precursors to assemble into RNA, and membrane precursors to assemble into membranes,” says Szostak. “I think that’s really remarkable.”

As Hanczyc and Fujikawa analyzed their new vesicles, they made an even more remarkable discovery. Some of the grains of montmorillonite actually wound up inside the vesicles.

Their next step was obvious. “It was very straightforward,” says Hanczyc. “You just mix the RNA with clay, and mix it with the fatty acids, and voilà, you have RNA on the clay particles inside the vesicles.”

Here was one possible way in which the pieces of the RNA world might have come together in cells that could grow and divide.

(My bold.)

You may be aware of this quote by renowned evolutionary biochemist Robert Shapiro in a published paper: "the evidence that is available at the present time does not support the idea that RNA, or an alternative replicator that uses the current set of RNA bases, was present at the start of life."

Depends what you mean by “the start of life”. The two studies I cited show that RNA can arise through the known laws of nature and the principles of natural selection.

The exact sequence of events may never be known. However, these experiments (and others), show that life can arise in accordance with the way we know organic molecules form and behave.

Shapiro is a skeptic who realizes the magnitude of the problem and is willing to admit it publicly. One of the main problems is that the D/RNA bases are very usntable, particularly (C) cytosine. That was the subject of the published article in which he made that quote.
There is reason for skepticism with regard to most of the origin of life theories. Perhaps you would enjoy his book (if you haven't already read it):
Origins: A Skeptic’s Guide to the Creation of Life in the Universe

I might, thanks for the reference. I already have a huge list of books still to read when I get the time, though. ;-)

[Gaurav]

Just nitpicking here...

You said, "No, it’s not random: some outcomes are more likely to succeed than others."

So what is random? Unless the outcome of a process is already determined/defined/devined the process is random!

Great blog... Love the ID bashing. hehe.