Session 2 – Origins of Life In this session we will look at the question of the origin of life in evolution We will look at several theories that evolutionists have presented to explain how life can come about naturally, and we will see the problems associated with them Much information is taken from Creation Ministries International (Creation.com) Biogenesis vs. Abiogenesis The law of biogenesis, attributed to Louis Pasteur, is the observation that living things come only from other living things, by reproduction Abiogenesis is the opposite, and says living things can arise and come about from non living material Pasteur has a famous experiment that most of us are familiar with He proved broadly the life comes from life “Life does not arise spontaneously but comes only from prior life, through reproduction… Although life certainly originated from nonliving matter at least once.” – integrated Principles of zoology, thirteenth edition, pg. 6 We need to be careful when we get into this debate that we know what we are talking about when we say life According to modern biology, life has five characteristics to it 1.Energy 2.Cells 3.Information 4.Evolution 5.Replication When we talk about creating life in the lab we are not talking about creating full size cells with these capabilities We are usually talking about creating some of the building blocks for life But the trick is not only building those things, but building them in an atmosphere and environment that they can survive in and eventually come together to create life The classic experiment for creating life in the lab is the Miller-Urey experiment (we will start here and then move onto more modern theories on the origins of life) Miller-Urey Ingredients - Methane - Ammonia - Hydrogen - Water vapor They excluded oxygen inside the atmosphere to prevent oxidation and breaking down or whatever was created They were able to make a few amino acids with the experiment Note also that the other products made in the process were toxic to life One vital thing to the experiment was no oxygen in the atmosphere If there’s no oxygen there’s no ozone, which means no protection from UV But if you add oxygen to the equation it will break down whatever is created Dr. A. J. Monty White “So the dilemma facing the evolutionist can be summed up this way: amino acids would not form in an atmosphere with oxygen and amino acids would be destroyed in an atmosphere without oxygen.” Many other problems exist Just because you have amino acids does not mean that you get all the proteins needed for life to exist We need the amino acids to bind in a very specific way (peptide bonds), and there are several chemical bonds they could form with each other that would make life impossible The average protein (polypeptide chain) has around 400 amino acids The other problem is this happening inside water, because water and hydrolysis tends to break bonds, not form them Because there were many problems with this experiment people have put together other experiments and theories to try to explain the origins of life from non living material Hydrothermal vent theory Researchers in Japan claim life can start on submarine hydrothermal vents deep inside the ocean because of the high temperatures in the environment that allow synthesis but also can quickly cool in surrounding water In the experiment they circulated 500 ml of a strong solution of glycine (0.1 M) through a chamber with high pressure The first chamber was heated mainly to 200– 250 ° C; from there, the liquid was injected at the rate of 8–12 ml/min into a cooling chamber kept at 0 ° C. In some of the runs, mild amounts of copper were added to the solution, which was also acidified to pH 2.5 by HCl at room temp The results? Chains of Amino Acids tetraglycine (yield 0.1%), hexaglycine (yield 0.001%) diketopiperazine (1%) The team leader, Koichiro Matsuno said: “For 10 years, underwater hydrothermal vents have been thought to be the place where life began—and we were able to prove it.” Did they show (like they claim) that life got started (or could get started) with these hydrothermal vents? Problems: The concentration of glycine of 0.1 M was far higher than could be expected in a real primordial soup Another question would be where the amino acid glycine came from to begin with The longest polymer created was hexaglycine (six long). Most enzymes though have hundreds! And the hexaglycine produced was found only in minuscule amounts. Another problem was the experiment only gave us homo-oligomer (all monomers/amino acids are the same) Living organisms are composed on 20 different amino acids, not just one The last problem is that the exclusive ‘lefthandedness’ required for living things is destroyed by heating. They didn’t test this though because they used the simplest (and only achiral) amino acid. (To be continued) Venter’s experiment The Guardian, had a headline Craig Venter creates synthetic life form Many people have a false understanding of this What he did was create a strand of DNA from scratch, and then placed it inside an already existing cell. In an online video, he said the following about the experiment: “It’s pretty stunning when you just replace the DNA software in the cell, and the cell instantly starts reading that new software, starts making a whole different set of proteins, and within a short while, all the characteristics of the first species disappear, and a new species emerges from this software that controls that cell going forward.” No doubt this was quite the accomplishment, but it wasn’t creating life in the lab, it was reprogramming existing life Some of the problems: He used already existing machinery to read his new strand of DNA, the problem is the machine can’t get here without the DNA… and the DNA is useless without the machine When it came to the software, he obtained the information from preexisting cells and then modified it and then synthesized DNA of his own (still very impressive, just not creating life in the lab) Venter used proteins from yeast in order to help join things together “The landmark achievement has yet to occur,” McGee (of the Center for Practical Bioethics in Kansas City, Mo) says. “What they’ve done is they’ve successfully transplanted DNA from one thing to another without noticeably harming the operation of the old DNA, as best they understand it, from their definition of its function. When I put it that way, it’s a hell of a lot less significant.” “It’s a great feat, but I wouldn’t call it an artificial organism,” Collins says [bioengineer James Collins, a Howard Hughes Medical Institute investigator at Boston University who was not involved in the study]. Synthetic, he contends, implies designed from scratch, not plagiarized from a natural genome. What’s more, the experiment required a recipient cell to provide the cytoplasm to hold the transplanted genome. “It’s small, but it’s an important quibble,” he says. RNA World This is one of the most popular theory for the origin of life, but has been adequately torn apart by not just creationists This theory says that RNA was the first form of self replicating life here on planet earth RNA has many features, like replication, acting as an enzyme, and more that lead people to believe it would come first What is RNA? For starters, it’s not a simple molecule These objections have been made: 1. RNA is too complex a molecule to have arisen prebiotically As we just saw, it’s not a simple arrangement of pieces that come together 2. RNA is inherently unstable Due primarily to oxygen RNA is unstable and is reactive (DNA is stable because it lacks an oxygen on the Carbon ring that RNA has) 3. There is no evidence that these molecules needed for RNA (sugar, nitrogen base, phosphate) would even be present in the ancient earth (oceans) at this time 4. Sugars and bases must connect and nucleosides must form with the N-bases There is no know way for this uphill reaction to occur for purine nucleosides in water, or for pyrimidine nucleosides in any environment (water or dry) 5. The environment must have been suitable with the correct pH levels and temperature There have been many other objections raised to this theory, but we don’t have time to cover them all One evolutionist laid out 19 steps (problems) that must be overcome for RNA world While many consider it the best theory still, they typically admit there are many problems Cairns-Smith’s clay mineral theory Because of many problems with the “primordial soup” idea that most theories utilize, some have suggested that life started not in this primordial soup, but clay. This theory says over time chemicals produced in the clay from sunlight came together in some sort of hypothetical self replication molecules (that eventually evolve to life today) They argue only clay has the two essential properties necessary for life, which is the capacity to store and transfer energy Along with this some clays can act as catalysts, which is used as further evidence That being said, the clay theory has it’s set of problems that have caused most evolutionary scientists to shy away from it When we look at Miller’s experiment, and the idea of primordial soup producing amino acids as the building blocks for life, he actually did that (even if it had problems) This theory is lacking experimental evidence for it, they haven’t showed building blocks for life arise in clays Another problem is the organic compounds get so attached to the clay that they can’t undergo any further chemical reactions Other theories do exist for the origin of life that we do not have time to cover These are many of the popular views out there today, although many of the authors admit that they haven’t solved the problem We will finish by looking at what may be the most significant problem for these theories, that we mentioned briefly early This problem applies to all theories Molecular Chirality Many of the molecules that are required for life to exist come in two forms These two forms are non superimpossable mirror images of one another That means that they are related in the same way that our right and left hands are That’s why it’s called chirality, from the Greek word for hand These two different forms are called enantiomers (opposite) or optical isomers, because they will rotate plane (polarized) light either to the right or to the left Here is an example of a molecule that is Chiral and can’t be superimposed on itself All amino acids, with the exception of glycine (the one used in that experiment earlier that we talked about) are Chiral Almost all biological polymers must by homochiral, meaning all the same sidedness Another term used is optically pure or 100 % optically active All amino acids in proteins are ‘left-handed’, while all sugars in DNA and RNA, and in metabolic pathways, are ‘right-handed’. If you have a 50/50 mixture of left- and righthanded forms it’s called racemate or racemic mixture Racemic polypeptides (amino acid chains) can’t form correct shapes unless they are all uniform on handedness Likewise, DNA cannot exist in the double helix if one building block is off So what’s the big problem? Look what this organic chemistry text book says on the topic “Synthesis of chiral compounds from achiral reagents always yields the racemic modification.’ and ‘Optically inactive reagents yield optically inactive products.” When you form chiral molecules from achiral material, you get a 50/50 left-right ratio The question is, how did these different chiral forms get separated to allow life to start? The odds of getting just right or just lend handed in the early formation of life by random chance is statistically insane (no one disagrees) For a small protein (100 amino acids) it’s 10^-30 of getting it correct That’s the probability for ANY homochiral polypeptide (of that size) to create a functional polypeptide with a specific arrangement of amino acids is much lower There have been methods put forward to try to solve this problem, but most evolutionists recognize that the problem is far from solved Any theory that attempts to explain the origins of life has to account for Chirality Wrapping things up [Attributing the origin of life to spontaneous generation.] However improbable we regard this event, it will almost certainly happen at least once…. The time… is of the order of two billion years.… Given so much time, the “impossible” becomes possible, the possible probable, and the probable virtually certain. One only has to wait: time itself performs the miracles.” — George Wald - In 'The Origin of Life', Scientific American (Aug 1964), 191, 46. Does adding time solve the problem? This whole idea of hiding in time is utilized by evolutionists all the time This mindset would say that eventually those 100 left handed amino acids would come together in a protein Here is a way to understand this… The odds of getting the correct handed amino acids randomly together (100 of them) is the same as flipping a coin and getting heads 100x Eventually it will happen, right? Chances are: 1 in 10,000,000000,000,000,000,000,000,000,000 If you flipped a coin once each second 24 hours a day, it would take 40 billion times the “accepted” age of the universe (13.75 billion years) to get that result! Time does not make all your problems go away, some things will never happen What if they successfully created life in the laboratory? What would it prove? Because of the problems explaining life evolving here on planet earth, many have suggested that it came from space This would be (normally) in the form of a bacteria on an asteroid that hits planet earth They try to push the problem to a different planet, and then they’ll make the excuse that we don’t know what the planet is like so it’s possible life can start there Memory Verse John 1:3: “All things were made through him, and without him was not any thing made that was made.”