Here’s a new paper published in the prestigious peer-reviewed science journal Nature, entitled “The oxidation state of Hadean magmas and implications for early Earth’s atmosphere”.
Evolution News explains what the paper is about.
A recent Nature publication reports a new technique for measuring the oxygen levels in Earth’s atmosphere some 4.4 billion years ago. The authors found that by studying cerium oxidation states in zircon, a compound formed from volcanic magma, they could ascertain the oxidation levels in the early earth. Their findings suggest that the early Earth’s oxygen levels were very close to current levels.
[…]Miller and Urey conducted experiments to show that under certain atmospheric conditions and with the right kind of electrical charge, several amino acids could form from inorganic compounds such as methane, ammonia, and water. Several experiments have been done using various inorganic starting materials, all yielding a few amino acids; however, one key aspect of all of these experiments was the lack of oxygen.
If the atmosphere has oxygen (or other oxidants) in it, then it is an oxidizing atmosphere. If the atmosphere lacks oxygen, then it is either inert or a reducing atmosphere. Think of a metal that has been left outside, maybe a piece of iron. That metal will eventually rust. Rusting is the result of the metal being oxidized. With organic reactions, such as the ones that produce amino acids, it is very important that no oxygen be present, or it will quench the reaction. Scientists, therefore, concluded that the early Earth must have been a reducing environment when life first formed (or the building blocks of life first formed) because that was the best environment for producing amino acids. The atmosphere eventually accumulated oxygen, but life did not form in an oxidative environment.
The problem with this hypothesis is that it is based on the assumption that organic life must have formed from inorganic materials. That is why the early Earth must have been a reducing atmosphere. Research has been accumulating for more than thirty years, however, suggesting that the early Earth likely did have oxygen present.
[…]This brings us back to that Nature letter, which offers another reason to question the reducing environment of the early Earth. The authors looked at the cerium oxidation levels within zircon. Zircon is a hard rock that forms from the solidification of magma. Several studies have been done with zircon because of its age and durability. (See here for a report on using zircon to determine when oceans and land were present on Earth.) Cerium (Ce) is an element that can be found in early Earth zircon. The ratio of cerium’s +3 and +4 oxidation states indicates the environmental conditions at the time the cerium was trapped in the zircon. Specifically, cerium’s oxidation ratio is related to the amount of oxygen in the atmosphere. The authors created cerium-infused zircon in the lab at various oxidative ratios to make a calibration curve to which they could then compare the early Earth samples.
Their findings not only showed that oxygen was present in the early Earth atmosphere, something that has been shown in other studies, but that oxygen was present as early as 4.4 billion years ago. This takes the window of time available for life to have begun, by an origin-of-life scenario like the RNA-first world, and reduces it to an incredibly short amount of time. Several factors need to coincide in order for nucleotides or amino acids to form from purely naturalistic circumstances (chance and chemistry). The specific conditions required already made purely naturalist origin-of-life scenarios highly unlikely. Drastically reducing the amount of time available, adding that to the other conditions needing to be fulfilled, makes the RNA world hypothesis or a Miller-Urey-like synthesis of amino acids simply impossible.
So here’s where we stand. If you are a materialist, then you need a reducing environment on the early Earth in order to get organic building blocks (amino acids) from inorganic materials. However, the production of these organic building blocks (amino acids) requires that the early Earth atmosphere be oxygen-free. And the problem with this new research, which confirms previous research, is that the early Earth contained huge amounts of oxygen – the same amount of oxygen as we have today. This is lethal to naturalistic scenarios for creating the building blocks of life on the Earth’s surface.
If you would like to read a helpful overview of the problems with a naturalistic scenario for the origin of life, check out this article by Casey Luskin.
The “origin of life” (OOL) is best described as the chemical and physical processes that brought into existence the first self-replicating molecule. It differs from the “evolution of life” because Darwinian evolution employs mutation and natural selection to change organisms, which requires reproduction. Since there was no reproduction before the first life, no “mutation – selection” mechanism was operating to build complexity. Hence, OOL theories cannot rely upon natural selection to increase complexity and must create the first life using only the laws of chemistry and physics.
There are so many problems with purely natural explanations for the chemical origin of life on earth that many scientists have already abandoned all hopes that life had a natural origin on earth. Skeptical scientists include Francis Crick (solved the 3-dimensional structure of DNA1) and Fred Hoyle (famous British cosmologist and mathematician), who, in an attempt to retain their atheistic worldviews, then propose outrageously untestable cosmological models or easily falsifiable extra-terrestrial-origin-of-life / panspermia scenarios2 which still do not account for the natural origin of life. So drastic is the evidence that Scientific American editor John Horgan wrote, “[i]f I were a creationist, I would cease attacking the theory of evolution … and focus instead on the origin of life. This is by far the weakest strut of the chassis of modern biology.”3
The article goes over the standard problems with naturalistic scenarios of the origin of life: wrong atmosphere, harmful UV radiation, interfering cross-reactions, molecular oxygen, meteorite impacts, chirality, etc.
Charles Thaxton explains the origin of life
Here’s a helpful little video on the problem from origin of life chemist Charles Thaxton, who authored “The Mystery of Life’s Origin” with Walter Bradley and Roger Olsen.
There’s another video like this one featuring Dean Kenyon, and you can get the video clips online here. I really wish someone would post it online. I have the video and ripped it from my VHS tape, so maybe I should do it! It’s a great interview. Both of these videos (Thaxton, Kenyon) are highly recommended for intermediate and advanced Christians. For beginners, I would recommed “Unlocking the Mystery of Life”, which you can watch for free right here:
If you are looking for a hot issue to put some time into, then this is a good place to start. And note that this problem of the building blocks of life is logically prior to the problem of forming functional sequences of amino acids (e.g. – proteins), which people like Stephen C. Meyer debate about. In debates on the origin of life, ID people usually just assume that the amino acids exist, and then get on with discussing the problem of generating sequences of amino acids and base pairs into sequences that exhibit specified complexity. But as you see from the research, it’s an unwarranted assumption – those building blocks are not a given, and the naturalist has to account for them.