What are the odds? – Evolution (Part 1)
I majored in Biochemistry and minored in Physics. I studied Biology at a molecular level, which is something most Biologists don’t do, and happens to be the level at which evolution is theorized to take place. There are two theories pertaining to evolution; naturalistic evolution and theistic evolution. When I use the word ‘evolution’ I’m referring to naturalistic evolution. This form of evolution assumes that all progression, from no living things at all, to a collection of amino acids, to single celled organisms, all the way to humans, happened completely naturally, by chance, without any outside interference. This is the form of evolution proposed by Darwin. It is the theory of evolution taught in schools and will typically be the form of evolution referred to when you hear it discussed.
Many people believe in evolution because it makes sense to them. Humans tend to believe the things we understand, and disregard things we don’t understand. When elementary, middle and high school students are shown a series of pictures of organisms that change slightly, and are told that it is an example of evolution, it makes sense to them. When they are told that mutations give organisms new traits that make them better adapted to live and so they survive and reproduce, that makes sense. It sounds nice and reasonable. So they believe it, they grow up and graduate from High School, and pretty soon most people believe in Evolution. High School students don’t know what it means for a mutation to occur. They don’t know how complicated life is at a molecular level. They don’t know many of the pictures of evolving organisms they saw in their high school textbooks were just artist renditions of what Biologists think happened. They aren’t taught that the theory of evolution is simply that; a theory. They don’t know how unscientific the theory is. So I’m going to explain these things that aren’t taught in high school, and show why a detailed explanation makes evolution seem a much less likely explanation for the origin of life.
There are two ways that data are stored; either analog or digital. Analog means streamlined. Digital means it is divided into fundamental units. The easiest way to picture this is to think of a digital clock and a clock with hands that sweep around. They both give the same information; the time. However, one does it in units. It shows a series of numbers that indicate the hour, minutes and seconds. An analog clock shows the time by the position the hands are in. A major difference between analog and digital information is that using an analog storage system gives you infinite possibilities. In other words, there are infinite combinations. It is kind of hard to grasp. Again, picture a clock with the hands. You can put the hands in any combination and they will convey a different time. You can move the hands the slightest bit and they will convey a different time. You may not be able to see the difference; if you look at a clock and it looks like it says it’s 2:30:00, and the second hand moves one angstrom, it’s still going to look like it’s 2:30:00. Analog is limited by the sensitivity of the instruments you use to measure it. With a digital watch the information stored is limited to a specific number of possibilities. 12 different hours, 60 different minutes and 60 different seconds; a digital watch can only convey 43,200 combinations of times. If you have a digital watch that measures hundredths of seconds this number goes up. Research laboratories may need to measure millionths of seconds, or even smaller units than that. However, there is always a limit when using digital measuring techniques.
An analog clock, on the other hand, has infinite combinations. Despite there being infinite locations the hands can be in, all of the locations can be covered. So just picture the second hand. In 60 seconds it travels completely around the clock. In that 60 seconds the hand covered infinite distinct positions.
All living organisms store information in digital and analog forms. There are 20 amino acids, which make up DNA and proteins in our bodies. DNA and proteins store most of the information for building life. The information in DNA is mostly digital; the information in proteins is digital and analog. Amino acids are arranged in a certain order. The order indicates specific information. Think of the alphabet; there are 26 letters, when you put them in a specific order they mean something. That is how DNA stores information. Proteins also convey information, but they convey information (and work) by the shape they are in. You can picture a triangle; pretend the shape of the triangle conveyed different information. If one corner was really pointy it would mean something different than when all the corners are the same angle. Or you can picture the clock with the second hand again. Every position the hand is in conveys something different. Proteins convey their information by the shape they are in, but they are also made of amino acids and the order of the amino acids is important as well. Proteins ‘do’ everything in a cell; proteins transport, they build, they divide the cells, they replicate DNA. Without proteins, cells wouldn’t ‘do’ anything, and so they wouldn’t be alive.
Pretend the following line is a strand of amino acids meant to form a protein:
The order of the amino acids (letters) in the line is very important for conveying what the protein should do. The shape is also important. So imagine the line was tied in the shape of a bow. This could mean that the protein helped to build cell walls. If it wasn’t in the shape of a bow it wouldn’t do anything. If it was tied in a different shape, like a figure 8, it might help relicate DNA. If it were a perfect circle it might transfer chemicals into the nucleus of the cell. The point is, the shape is important. If it were in a figure 8 it could be a figure 8 with the ends of the strands in the very center, or the ends of the strands could at the ends of one of the loops, or they could be anywhere in between. If the ends of strands were at the center it would help replicate DNA by dividing the strands. If the ends of the strands were at the very top of the figure 8 it would help replicate DNA by bringing the matching amino acids to bind to half of the strand. And if the ends of the strands were at the very bottom of the figure 8 it just wouldn’t work. The location of each amino acid within the shape is also important.
Now, imagine that instead of being 91 amino acids long, it is several thousand amino acids long. Remember that each of the amino acids can be one of 22, and it is important that each one is the right one. I think it is easier to picture a pearl necklace, with each pearl being one of 22 colors, and the pearl necklace is several thousand pearls long. Instead of a figure 8, imagine dropping the pearl necklace into a glass. It clumps up into a certain shape. How many times would you have to drop the pearl necklace into the glass before it had formed every shape possible? The answer is infinity; a shape is an analogue form of storing data, there are infinite shapes the pearl necklace can take. It doesn’t have to just be a glass, either, you could just drop it in a pile on the floor (also an infinite number of times) or into a bowl, or clump it into a sphere. The pearl necklace can take infinite shapes, and in each of these shapes the location of each pearl is important. Imagine you had dropped it into a groove of a figure 8, so it would stay in the same shape, but you could slide it so the pearls would move along the grooves until every pearl had been in every location. You pinch the pearl in the center where the necklace crosses, then slide it around one loop until it is at the center again, then slide it around the second loop until it returns to where it started. Also, each amino acid pearl can be rotated. Imagine you put a dot on each pearl. The dot could be facing up when you look down into your figure 8 groove, or it could be facing down, or to the left or right. Each pearl can be spun into several directions, which is also important for making sure the protein has the right function. It is easiest to picture in a figure 8 shape, but most proteins are more closely shaped like a pearl necklace clumped into a sphere. So, if you could clump it into a sphere and it would keep its shape while you slid one pearl completely around until it returned to its original spot, that would be a more accurate portrayal of a protein and the potential shapes it can take to portray information.
So, what are the chances that you could just randomly build a specific protein? Lets say you want a protein that can build a cell wall. Because right now we’re at the beginning of Earth; there are no living things, just a pile of amino acids. In order to build a living thing we need to start with a cell, and to build a cell we can start with a cell wall (technically it’s a membrane, but it is the outer ‘wall’ of the cell). We can use statistics to calculate your chances. We can make it an easy protein. It is only 51 amino acids long. You could choose from one of 22 for the first amino acid, and pick another one for the second, and another one for the third, until you get to 51. We can calculate the number of possible combinations: it is 22^51, or 22 times 22, 51 times. So your chance of getting the right combination is 1/22^51. We can pretend you got it right. After all, one in 22^51, or 2.91 e67, isn’t a horrible chance. (I’m sorry, that was sarcasm. 1 in 22^51 is an atrocious chance. If your odds of winning the Publisher Clearing House $1,000,000 jackpot are 1 in 1,75O,OOO,OOO, you would win 16600000000000000000000000000000000000000000000000000000000, or 1.66 e56, times before coming up with the right combination for the protein.)
Actually, we can do a few more quick comparisons to try to put proteins sizes into perspective. If you try to calculate 22\^400 (for an average protein), you probably can’t. Your computer probably can’t calculate it, and your calculator probably can’t either. If you type it into a good calculate, it will tell you the answer is ‘infinity’. The answer, of course, isn’t actually infinity; it’s just very, very large. The answer is 6e536. Which is 6 with 536 zeros after it. That is just 22\^400, which is smaller than many proteins. Insulin, the first protein to be completely sequenced, is 51 amino acids long. Hemoglobin is 141 amino acids long. The average yeast protein is 466 amino acids long. The largest proteins in the human body are about 27,000 amino acids long. But, single celled organisms wouldn’t have proteins that large, so for the purposes of demonstrating how absurd the theory of evolution is, larger proteins are irrelevant. For convenience sake we can use 2.91e67, the chances of randomly getting the sequence for insulin right. To compare that number to something you might begin to comprehend, the estimated number of stars in the universe is 1 e21, or 1000000000000000000000. That is a very large number, but it doesn’t come close to 2.91 e67.
I don’t want you to forget where I’m going with this. We’re trying to make one protein out of amino acids. A relatively small protein made out of only 51 amino acids, which will perform one specific job in helping to build a single-celled organism. The amino acids need to be in a specific order, and the chances of the amino acids randomly binding into the correct order is the inconceivably large 2.91 e67. You can’t even say the chance is astronomically large, because we’ve compared it and it blows ‘astronomically’ out of the water. Once the amino acids have bound in that particular order, it needs to fold into the right shape so it can perform the right function. There are infinite shapes it could take, and in each shape there are infinite locations for each amino acid, as well as several directions each amino acid could face. Proteins are the basic, fundamental working unit of a cell. Without proteins DNA would be useless, because the proteins are what read and follow the directions on DNA.
Now I’m going to explain a few things about statistics and probabilities. You have probably learned basic statistics at some point, and some of it is intuitive. If you have a box with a blue marble and a red marble, and you randomly pull one out, you have a 1 in 2 chance of getting the red marble. There are two marbles, you are grabbing one of them. Another way of writing that is 1/2 chance. Your probability of picking the red marble is 1/2. Now, if you had a box with 6e536 marbles, and one of them is red, your chances of picking the red marble are 1/6e536. That number is very, very close to zero, but it isn’t zero. That is the probability of a protein being formed with the amino acids in the correct order to perform a specific needed function. There is a non-zero probability of it happening. However, there are infinite shapes it could fold into. Because there are infinite shapes, the probability of it folding into the right shape is 1/∞, which is basically zero. Technically it is not zero; the limit of 1/n as n approaches infinity is zero. Which means 1/∞ is basically zero.
Now, we know that, even though there are infinite shapes an amino acid can take, they can go through all these shapes in less than an infinite amount of time. After all, an analogue clock travels through infinite possible combinations in just twelve hours. So how long would it take a protein to do the same thing? In 1969 Cyrus Levinthal calculated that the average protein would have to sample 1×10 e143 different conformations (shapes) if it were to just randomly wander through every three dimensional shape. If it took just a nanosecond, 1 e-9 seconds, in each conformation, it would take 3×10 e126 years.
3 with 126 zeros, years.
Interestingly, the universe is only thought to be 1.4 x 10e10 years old. That’s 14000000000 years the universe has existed. One protein would take 3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 years to randomly wander through every shape.