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Polemics

The origin of life, part 1 of 2: the building blocks of life

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The origin of life

There are two problems related to the origin of the first living cell, on atheism:

  1. The problem of getting the building blocks needed to create life – i.e. the amino acids
  2. The problem of creating the functional sequences of amino acids and proteins that can support the minimal operations of a simple living cell

Normally, I concede the first problem and grant the atheist all the building blocks he needs. This is because step 2 is impossible. There is no way, on atheism, to form the sequences of amino acids that will fold up into proteins, and then to form the sequences of proteins that can be used to form everything else in the cell, including the DNA itself. But that’s tomorrow’s topic.

Today, let’s take a look at the problems with step 1.

The problem of getting the building blocks of life

Now you may have heard that some scientists managed to spark some gasses to generate most of the 20 amino acids found in living systems. These experiments are called the “Miller-Urey” experiments.

The IDEA center has a nice summary of origin-of-life research that explains a few of the main problems with step 1.

Miler and Urey used the wrong gasses:

Miller’s experiment requires a reducing methane and ammonia atmosphere,11, 12 however geochemical evidence says the atmosphere was hydrogen, water, and carbon dioxide (non-reducing).15, 16 The only amino acid produced in a such an atmosphere is glycine (and only when the hydrogen content is unreasonably high), and could not form the necessary building blocks of life.11

Miller and Urey didn’t account for UV of molecular instability:

Not only would UV radiation destroy any molecules that were made, but their own short lifespans would also greatly limit their numbers. For example, at 100ºC (boiling point of water), the half lives of the nucleic acids Adenine and Guanine are 1 year, uracil is 12 years, and cytozine is 19 days20 (nucleic acids and other important proteins such as chlorophyll and hemoglobin have never been synthesized in origin-of-life type experiments19).

Miller and Urey didn’t account for molecular oxygen:

We all have know ozone in the upper atmosphere protects life from harmful UV radiation. However, ozone is composed of oxygen which is the very gas that Stanley Miller-type experiments avoided, for it prevents the synthesis of organic molecules like the ones obtained from the experiments! Pre-biotic synthesis is in a “damned if you do, damned if you don’t” scenario. The chemistry does not work if there is oxygen because the atmosphere would be non-reducing, but if there is no UV-light-blocking oxygen (i.e. ozone – O3) in the atmosphere, the amino acids would be quickly destroyed by extremely high amounts of UV light (which would have been 100 times stronger than today on the early earth).20, 21, 22 This radiation could destroy methane within a few tens of years,23 and atmospheric ammonia within 30,000 years.15

And there were three other problems too:

At best the processes would likely create a dilute “thin soup,”24 destroyed by meteorite impacts every 10 million years.20, 25 This severely limits the time available to create pre-biotic chemicals and allow for the OOL.

Chemically speaking, life uses only “left-handed” (“L”) amino acids and “right-handed” (“R)” genetic molecules. This is called “chirality,” and any account of the origin of life must somehow explain the origin of chirality. Nearly all chemical reactions produce “racemic” mixtures–mixtures with products that are 50% L and 50% R.

Two more problems are not mentioned in the article. A non-peptide bond anywhere in the chain will ruin the chain. You need around 200 amino acids to make a protein. If any of the bonds is not a peptide bond, the chain will not work in a living system. Additionally, the article does not mention the need for the experimenter to intervene in order to prevent interfering cross-reactions that would prevent the amino acids from forming.

The progress of science

As science has progressed, the discoveries have proved out the need for a Creator and Designer in every area – the big bang, cosmic, galactic and stellar fine-tuning, the Cambrian explosion, etc…. and even the origin of life.

“More than 30 years of experimentation on the origin of life in the fields of chemical and molecular evolution have led to a better perception of the immensity of the problem of the origin of life on Earth rather than to its solution. At present all discussions on principal theories and experiments in the field either end in stalemate or in a confession of ignorance. New lines of thinking and experimentation must be tried.”

(Dose, Klaus, “The Origin of Life: More Questions Than Answers,” Interdisciplinary Science Reviews, Vol. 13, No. 4, 1988, p.348.)

Meanwhile, atheists are left to have blind faith that the progress scientists have made during decades of research will be miraculously overturned by new evidence that their beloved unobservable Flying Spaghetti Monster, (peas be upon him), did it. Hey! Don’t blaspheme against the non-supernatural powers of his noodly appendage! (Two Ph.Ds in biology will not save you from the wrath of the Darwoid cultists!)

To see how bad this gets for atheists, watch this video where Dawkins says that unobservable aliens evolved somewhere else and then seeded the Earth with life. He has no evidence that these aliens did evolve (no fossil record), and even worse, he does not know whether they even exist. Nevertheless, that is the state of atheism today – an unobservable Flying Spaghetti Monster evolved somewhere else and seeded the Earth with life.

What else could have happened?

Further study

One of my favorite resources on the origin of life is this interview from the University of California with former atheist and origin of life researcher Dean Kenyon. Kenyon, a professor of Biology at San Francisco State University, wrote the textbook on “chemical evolution”, which is the view that chemicals can arrange themselves in order to create the first living cell, without intervention.

This interview from the University of California with another origin of life researcher, Charles Thaxton, is also one of my favorites.

You’ll need Quicktime to see the videos, or buy the videos from ARN. (Kenyon, Thaxton) I have both of them – they rock!

Commentary

Scientific American assesses naturalistic explanations for the origin of life

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From Scientific American. (H/T Letitia via Mary)

Excerpt:

As recently as the middle of the 20th century, many scientists thought that the first organisms were made of self-replicating proteins. After Francis Crick and James Watson showed that DNA is the basis for genetic transmission in the 1950s, many researchers began to favor nucleic acids over proteins as the ur-molecules. But there was a major hitch in this scenario. DNA can make neither proteins nor copies of itself without the help of catalytic proteins called enzymes. This fact turned the origin of life into a classic chicken-or-egg puzzle: Which came first, proteins or DNA?

RNA, DNA’s helpmate, remains the most popular answer to this conundrum, just as it was when I wrote “In the Beginning…” Certain forms of RNA can act as their own enzymes, snipping themselves in two and splicing themselves back together again. If RNA could act as an enzyme, then it might be able to replicate itself without help from proteins. RNA could serve as gene and catalyst, egg and chicken.

But the “RNA-world” hypothesis remains problematic. RNA and its components are difficult to synthesize under the best of circumstances, in a laboratory, let alone under plausible prebiotic conditions. Once RNA is synthesized, it can make new copies of itself only with a great deal of chemical coaxing from the scientist. Overbye notes that “even if RNA did appear naturally, the odds that it would happen in the right sequence to drive Darwinian evolution seem small.”

The RNA world is so dissatisfying that some frustrated scientists are resorting to much more far out—literally—speculation. The most startling revelation in Overbye’s article is that scientists have resuscitated a proposal once floated by Crick. Dissatisfied with conventional theories of life’s beginning, Crick conjectured that aliens came to Earth in a spaceship and planted the seeds of life here billions of years ago. This notion is called directed panspermia. In less dramatic versions of panspermia, microbes arrived on our planet via asteroids, comets or meteorites, or drifted down like confetti.

John Horgan is not a Christian, nor even a theist. This is the state of the art if you are a naturalist.

Basically, you have at most a couple hundred million years from the time the Earth cools to the appearance of first life. You are unlikely to get one measly protein without an intelligence arranging the amino acids. This is assuming we spot you a favorable environment for creating amino acids without intervention. And then there would still be the problem of sequencing the proteins.

Atheists oppose science and evidence

Theists support science and evidence

News

New peer-reviewed paper endorses irreducible complexity and intelligent design

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From Evolution News.

Excerpt:

A peer-reviewed paper, “Information and Entropy — Top-Down or Bottom-Up Development in Living Systems?,” by University of Leeds professor Andy McIntosh in the International Journal of Design & Nature and Ecodynamics expressly endorses intelligent design (ID) via an exploration of a key question in ID thinking…

Notice that this journal is NOT related to the intelligent design movement in any way – this is a mainstream peer-reviewed journal.

The author of the paper has two goals:

(1) First, he defines the term “machine” (a device which locally raises the free energy) and observes that the cell is full of machines. Such machines pose a challenge to neo-Darwinian evolution due to their irreducibly complex nature.
(2) Second, he argues that the information in living systems (similar to computer software) uses such machines and in fact requires machines to operate (what good is a program without a computer to run it?). An example is the genome sitting on the DNA molecule. From a thermodynamics perspective, the only way to make sense of this situation is to understand that the information is non-material and constrains the thermodynamics so that the local matter and energy are in a non-equilibrium state.

And a bit later:

…the presence of information is the cause of lowered logical entropy in a given system, rather than the consequence.

…[T]here is a perfectly consistent view which is a top-down approach where biological information already present in the phenotypic creature (and not emergent as claimed in the traditional bottom-up approach) constrains the system of matter and energy constituting the living entity to follow intricate non-equilibrium chemical pathways. These pathways whilst obeying all the laws of thermodynamics are constantly supporting the coded software which is present within … Without the addition of outside intelligence, raw matter and energy will not produce auto organization and machinery. This latter assertion is actually repeatedly borne out by experimental observation – new machinery requires intelligence. And intelligence in biological systems is from the non-material instructions of DNA.

You can read more about the paper here.

I wonder what the fallout will be from this bold act?

Luskin writes:

I have no doubt that the editors of International Journal of Design & Nature and Ecodynamics will take much heat for publishing this paper. Even though they make it clear that “[t]he reader should not assume that the Journal or the reviewers agree with the conclusions of the paper,” they should be commended for their courage in publishing it it and calling it a “a valuable contribution that challenges the conventional vision that systems can design and organise themselves.” They write, “The Journal hopes that the paper will promote the exchange of ideas in this important topic” — showing that there is hope for true academic freedom on the debate over ID in some corners of the scientific community.

I think it’s good that some of the more honest journals are starting to post these research papers on ID without endorsing them explicitly. It’s important for people to have a free and open debate about these things. I’m sure that the other side is going to try to come back now with a published response – maybe even with some quality research. And that’s how science is supposed to march forward. We don’t want to get into the situation where there are more of these big “Climategate” scandals in biology. Let all the opposing views be heard.