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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

Harvard astrophysicist backs the Rare Earth hypothesis

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What is the Rare Earth hypothesis?

It’s the thesis of a recent book written by two scientists at the University of Washington.

Here’s the blurb:

What determines whether complex life will arise on a planet? How frequent is life in the Universe?

In this exciting new book, distinguished paleontologist Peter D. Ward and noted astronomer Donald Brownlee team up to give us a fascinating synthesis of what’s now known about the rise of life on Earth and how it sheds light on possibilities for organic life forms elsewhere in the Universe.

Life, Ward and Brownlee assert, is paradoxically both very common and almost nowhere. The conditions that foster the beginnings of life in our galaxy are plentiful. But contrary to the usual assumption that if alien life exists, it’s bound to be intelligent, the authors contend that the kind of complex life we find on Earth is unlikely to exist anywhere else; indeed it is probably unique to our planet.

With broad expertise and wonderful descriptive imagery, the authors give us a compelling argument, a splendid introduction to the emerging field of astrobiology, and a lively discussion of the remarkable findings that are being generated by new research. We learn not only about the extraordinary creatures living in conditions once though inimical to life and the latest evidence of early life on Earth, but also about the discoveries of extrasolar planets, the parts Jupiter and the Moon have played in our survival, and even the crucial role of continental drift in our existence.

Insightful, well-written, and at the cutting edge of modern scientific investigation, Rare Earth should interest anyone who wants to know about life elsewhere and gain a fresh perspective on life at home which, if the authors are right, is even more precious than we may ever have imagined.

And here’s a review by Library Journal:

“Renowned paleontologist Ward (Univ. of Washington), who has authored numerous books and articles, and Brownlee, a noted astronomer who has also researched extraterrestrial materials, combine their interests, research, and collaborative thoughts to present a startling new hypothesis: bacterial life forms may be in many galaxies, but complex life forms, like those that have evolved on Earth, are rare in the universe. Ward and Brownlee attribute Earth’s evolutionary achievements to the following critical factors: our optimal distance from the sun, the positive effects of the moon’s gravity on our climate, plate tectonics and continental drift, the right types of metals and elements, ample liquid water, maintainance of the correct amount of internal heat to keep surface temperatures within a habitable range, and a gaseous planet the size of Jupiter to shield Earth from catastrophic meteoric bombardment. Arguing that complex life is a rare event in the universe, this compelling book magnifies the significance — and tragedy — of species extinction. Highly recommended for all public and academic libraries.”

Note that Peter Ward is a militant atheist (he has debated against Stephen C. Meyer), and Donald Brownlee is an agnostic. These are not Christians, nor are they even theists. However, I have the book, I have read the book, and I recommend the book. I usually have this book on my shelf at work for show-and-tell.

Now for the latest news about the hypothesis of the book. (H/T Brian Auten of Apologetics 315)

There are always going to be optimistic predictions by scientists who need to attract research funding, but those are hopes and speculations. The data we have today says Earth is rare. The number of conditions required for complex life of any kind is too high for us to be optimistic about alien life in this galaxy, at least. And as the number of requirements for life roll in, the odds of finding alien life that can contact us get slimmer and slimmer.

From the UK Daily Mail. (H/T Peter S. Williams)

Excerpt:

Dr Howard Smith, a senior astrophysicist at Harvard University, believes there is very little hope of discovering aliens and, even if we did, it would be almost impossible to make contact.

So far astronomers have discovered a total of 500 planets in distant solar systems – known as extrasolar systems – although they believe billions of others exist.

But Dr Smith points out that many of these planets are either too close to their sun or too far away, meaning their surface temperatures are so extreme they could not support life.

Others have unusual orbits which cause vast temperature variations making it impossible for water to exist as a liquid – an essential element for life.

Dr Smith said: ‘We have found that most other planets and solar systems are wildly different from our own.

‘They are very hostile to life as we know it.’

‘The new information we are getting suggests we could effectively be alone in the universe.

‘There are very few solar systems or planets like ours. It means it is highly unlikely there are any planets with intelligent life close enough for us to make contact.’ But his controversial suggestions contradict other leading scientists – who have claimed aliens almost certainly exist.

These arguments are actually quite useful, and I include them in my standard list of scientific arguments for theism. (See below) You have to know this stuff cold. Most people believe in aliens because they watched movies made by artists. As a result, they think that humans are nothing special and that God is not interested in us in particular. Which is very convenient for them, because it means they can do whatever they want and not care what God thinks about what they are doing. If you want to defend against the idea that humans are nothing special, and that we were not placed here for a purpose, and that we are not accountable and obligated to seek and know the Creator/Designer, then you’ll need more than feelings. You’ll need science. You’ll need the best science available.

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