Challenges in Chemical Evolution Exploration

1. 2 Peter 3:3-5 3 Knowing this first, that there shall come in the last days scoffers, walking after their own lusts, 4 And saying, Where is the promise of his coming? For since the fathers fell asleep, all things continue as they were from the beginning of the creation. 5 For this they willingly are ignorant of, that by the word of God the heavens were of old, and the earth standing out of the water and in the water:

2. Chemical Evolution Timothy G. Standish, Ph. D.

3. The Likely and the Unlikely • Science is about predicting what is likely and what is unlikely. Everyone is in agreement that the events leading to production of living organisms are unlikely. • It has been argued that given massive lengths of time and a universe to work in, the unlikely becomes likely: • Given infinite time, or infinite opportunities, anything is possible. The large numbers proverbially furnished by astronomy, and the large time spans characteristic of geology, combine to turn topsy-turvy our everyday estimates of what is expected and what is miraculous. Richard Dawkins. 1989. The Blind Watchmaker: Why the evidence of evolution reveals a universe without design. W. W. Norton and Co., NY, p 139.

4. Four Postulated Stages of Chemical Evolution • Chemical evolution is the spontaneous production of the molecular components of cells that had to be produced prior to evolution of the first cell: 1) Abiotic synthesis of organic monomers 2) Abiotic synthesis of organic polymers 3) Self assembly of protobionts 4) Evolution of a genetic system • We will concentrate on the first two steps

5. Step 1: Abiotic Synthesis of Organic Monomers • The monomers that make up polymers in living cells are reduced carbon compounds • Can’t happen in modern world due to oxidizing atmosphere • 1920s A. I. Oparin (Russia) and J. B. S. Haldane (Great Britain) postulated that as spontaneous synthesis of reduced organic molecules is impossible in an oxidizing environment, the earth must have had a reducing atmosphere • 1953 Miller and Urey designed a device to test the hypothesis that given the right conditions, organic monomers could be produced

6. The Miller-Urey Device NH3 H2 CH4 H2O Sample

7. Products of Miller and Urey’s Device • After several days of operation, the Miller-Urey device produced a brown organic substance in which, either in this experiment or subsequent variations, was found many of the basic building blocks of: • Proteins (amino acids) • Nucleic acids (ribose, purines and pyrimidines) • Polysaccharides (sugars) • Fats (fatty acids and glycerol) • Note that it was the building blocks that were found, not the actual macromolecules • Along with these building blocks, there were many other molecules not found in organisms

8. Did Miller and Urey Prove Chemical Evolution? Six reasons that it does not prove chemical evolution: • Oparin’s reducing conditions were postulated because they are conditions allowing reduced organic molecule production, not because of compelling evidence these conditions ever existed on earth. • Reduced organic products were not the result of random chance, but of a device that had been carefully designed and constructed. • Products were not enriched in the chemicals that make up organisms. This is a particular problem when it comes to stereoisomers. • No organisms were actually made. • Even if organisms were made in this way, this would not prove it to be how things actually happened, it only shows it to be one possible way. • Accumulation of organic monomers is only the first step in chemical evolution.

9. Step 2: Abiotic Synthesis of Organic Polymers • It has been postulated that the monomer building blocks produced under conditions resembling those in the Miller-Urey experiment were joined together to make polymers • Experiments have been done that demonstrate this is possible in the absence of living cells or cell products like enzymes • The sequence in which monomers are joined together to make polymers is vital to the function of polymers like DNA and proteins. • No mechanism has been proposed for joining monomers in meaningful sequences, thus abiotically synthesized organic polymers are assumed to have been random in sequence.

10. A Polymerization ExperimentImai et al, 1999 Science 283:831-833 • Imai et al’s device “simulated the pressure and temperature conditions of the hydrothermal circulation of water” • “However, there were still some large differences [from real hydrothermal vents], for instance, in pH, CO2, Na and Cl contents.” • 100 mM glycine in pure water was circulated in the system alternating regimes of high and low temperature and pressure with each circuit • 2 mM diketopiperazine, 1mM triglycine and 0.4 mM diglycine resulted once close to steady state condtions were reached • In the presence of Cu++ and low pH, small 0.001 mM concentrations of up to hexaglycine were produced

11. Imai et al’s Device Cooling Heating Depressurization Sample removal Pressurization

12. Random Sequences are Unlikely to be Meaningful or Useful • Random sequences of amino acids are analogous to random sequences of letters: • ldjfire vireahdftrfd • grvcnlkertpoildrirti • ugcrtrrtadhk jjkvhvf • jmvcbkvbkjhcguvdrttr • k jfvukvfkhjfvkhj he • Random sequences are unlikely to be meaningful

13. Yes, It Is Unlikely . . . But • The argument is not that the origin of life was a likely event, but that given sufficient time and resources chance events could produce the first organism that could then be acted on by the guiding hand of natural selection • So what are the resources available for the production of the first/simplest organism? Is it really the universe? • “The Monera (for instance, chromacea and bacteria), which consist only of this primitive protoplasm, and which arise by spontaneous generation from these inorganic nitrocarbonates, may thus have entered upon the same course of evolution on many other planets . . .” • Haeckel, Ernst. 1900. The Riddle of the Universe at the Close of the Nineteenth Century. Translated by Joseph McCabe. Harper and Brothers Publishers, NY, p 369.

14. Space and Time • The conditions necessary to produce reduced carbon compounds like those produced in the Miller-Urey experiment have not, so far, been found elsewhere in the universe • In reality, the conditions needed for life seem to only be present in a tiny fraction of the universe and we happen to be living on it. • Time is the other element needed, and this is a real problem • Even if the conventional interpretation of the fossil record is used, life seems to have appeared very soon (a few million, not billions of years) after water appeared on earth

15. Conventional History Of The Earth 0 Human fossils Cenozoic Mesozoic Last dinosaur fossils 500 First reptile fossils Paleozoic First land plant fossils 1,000 1,500 Precambrian 2,000 Millions of Years BP 2,500 3,000 3,500 Origin of life 4,000 4,500 -First multicellular animal fossils -First eukaryotic fossils -Atmospheric Oxygen accumulation (from cyanobacteria) -First fossil prokaryotes -Crust forms -Formation of the earth

16. Newer Ideas • Mars may have served as life’s incubator as it cooled before earth and had a moist environment. • Life, in the form of bacteria or blue-green algae, was transferred to earth when chunks of Mars knocked off by collisions with comets etc. fell to earth. • This general idea is not new. Francis Crick called it “panspermia” in Life Itself where he says the earth was seeded with life from space (Hoyle may also have published something similar) • None of this makes explanations simpler, just more complex (should Ockham’s Razor be invoked?)

17. The Information Catch-22 “With only poor copying fidelity, a primitive system could carry little genetic information without L [the mutation rate] becoming unbearably large, and how a primitive system could then improve its fidelity and also evolve into a sexual system with crossover beggars the imagination.” Hoyle F., "Mathematics of Evolution", [1987], Acorn Enterprises: Memphis TN, 1999, p 20

18. Evolution . . . So 20th Century “In the realm of science, scholars such as William Dembski and Michael Behe have been demonstrating how the order in the universe is evidence that it has been intelligently designed. ‘No!’ say the Darwinists. ‘Everything has to be random!’ But the evolutionists are the ones who sound so outdated, so 20th century.” Veith, Gene E. 2000. Reality makes a comeback. World Magazine Feb. 12, Vol. 15, No 6

19. Faith In One Unverified Idea • “But what if the vast majority of scientists all have faith in the one unverified idea? The modern ‘standard’ scientific version of the origin of life on earth is one such idea, and we would be wise to check its real merit with great care. Has the cold blade of reason been applied with sufficient vigour in this case? Most scientists want to believe that life could have emerged spontaneously from the primeval waters, because it would confirm their belief in the explicability of Nature the belief that all could be explained in terms of particles and energy and forces if only we had the time and the necessary intellect. They also want to believe because their arch opponents - religious fundamentalists such as creationists - do not believe in life's spontaneous origin. It is this combative atmosphere which sometimes encourages scientists writing and speaking about the origin of life to become as dogmatic and bigoted as the creationist opponents they so despise.” • Scott A., "The Creation of Life: Past, Future, Alien," Basil Blackwell: Oxford UK, 1986, p 111-112

20. The RNA World • Once RNA is synthesized, it can make new copies of itself only with a great deal of help from the scientist, says Joyce of the Scripps Clinic, an RNA specialist. “It is an inept molecule,” he explains, “especially when compared with proteins.” Leslie E. Orgel of the Salk Institute for Biological Studies, who has probably done more research exploring the RNA-world scenario than any other scientist, concurs with Joyce. Experiments simulating the early stages of the RNA world are too complicated to represent plausible scenarios for the origin of life, Orgel says. “You have to get an awful lot of things right and nothing wrong,” he adds. • Horgan J. 1991. "In The Beginning...," Scientific American, February, p 103. Ellipsis in original

21. The End