Chapter Two : The Grand Design
It makes sense to start with what we know. We actually know a lot.
We have scientific evidence that shows that the Earth began to form out of the primordial gasses that originated the solar system about 5.38 years ago. Life could not possibly have come to exist on Earth before this time because there was no Earth before this time. In fact, there really wasn’t any Earth before about 4.28 billion years ago: this was when the elements that made up the Earth were finally cool enough to form into solid rocks that became a permanent part of the world. (There were some few rocks before this time but they were like icebergs floating in a sea of molten magma, which melted and solidified as the temperature changed in different seasons. It wasn’t until 4.28 billion years ago that the Earth was cool enough to form the part of the world we now call the ‘crust.’
When did life first come to exist?
Scientists have found fossils of a specific kind of life, life built around the molecule DNA, that have been dated to 3.58 billion years ago, about 700 million years after the crust began to form on the cooler parts of the planet. We will look at life based on DNA shortly and see that ALL DNA-based life has certain characteristics that make it extremely complicated. Scientists have only been able to analyze the processes that take place in DNA-based life for a very short time. But they have found that certain processes with amazing complexity take place in all such life forms. The very first DNA-based life forms on Earth used the exact same ‘genetic code’ that the cells of human bodies use to reproduce themselves, to form proteins, and to do the other things that are needed for life processes to take place. The very first life forms that left fossils that contain DNA. Scientists have sequenced the DNA to determine the coding mechanisms. These coding mechanisms are identical to the mechanisms that code for the proteins in the cells of human beings. They are incredibly complex.
A Critical Part of Our History
If one era of history has complex life, and another era does not have it, there must be an era when something happened that caused the transition from ‘no life’ to ‘extremely complex DNA-based life’ to take place.
There must be some kind of ‘transitional era.’ This era may have been extremely short—perhaps only a few microseconds—but it is a critical part of our history.
Why would we care about this era?
The events during this era will give us a great deal of insight about the different premises for what we may call ‘the meaning of life,’ or the reasons that humans and other life forms exist at all.
If we should determine that the process we call ‘life’ is simply a very advanced functioning of some set of chemical and quantum-mechanical processes that simply happened, as a result of some accidental event of nature (lighting striking a ‘soup’ of naturally occurring chemicals, for example), we could justify accepting that life has no meaning and there are no philosophical rules for existence.
On the other hand, if find evidence for the description of the period when life came to exist on this Earth that matches the description in the books of the Abrahamic religions (including Islam, Judaism, and Christianity), we may determine that life was created to please an all-powerful invisible being that lives in the sky; we may find that man was created in the image of the all powerful being to keep him company; and we may end up with evidence that tell us that all events that take place on Earth, including wars, take place because the being with higher powers wants them to take place. We may find evidence that the meaning of life is exactly what the religious people claim it is: we are here to worship the invisible being, work so we can provide money to the people who represent him, and devote our life to supporting the nations that the invisible being built, in the hope that we can please him and get his assistance in the conflicts between the nations where we live and the other nations of the world.
Abrahamic texts:
All Abrahamic texts are built on the descriptions in the book of Genesis, which describes the creation of the world and the events that led up to the life of Abraham. Here is a link to Genesis, which will allow you to search for references to Abraham and see how he is introduced.
But there are other possibilities:
The ‘era’ that led to DNA-based life being on Earth may have started when an object that contained DNA and whatever was needed to keep this DNA alive arrived from somewhere off of this world.
If we accept that this may have happened—that it is one possible explanation for the way life came to exist on this world—we find we have new options for understanding the foundation of the ‘meaning of life’ that we did not have if we failed to consider it. We no longer have to choose between the idea that ‘life has no meaning at all’ (which comes from the idea that random natural processes created it) OR that ‘an invisible superbeing with magic powers directs everything on this world and we are here to do this being’s will’ (which comes from the idea that we were created by a being with super-natural, super-human, and super-scientific powers).
If we start with the idea that DNA-based life may at least possibly have a non-Earth origin, we are forced to think a little bit before we can understand the meaning of life, why we are here, and where we might possibly be going from here.
Before we start our analysis, it makes sense to look at some more evidence. What happened immediately after life came to exist on this world? Scientists have been able to put together a pretty good picture of these events. Perhaps understanding these events may help us figure out the most likely way life came to exist on this world.
Terraforming the Earth
The first living things we know were on Earth are a kind of organism scientists now calls ‘cyanobacteria.’ These organisms were recently renamed; their old name was ‘blue-green algae.’ Originally, these organisms were thought to be very simple living things that operated through mechanisms that are far simpler than the mechanisms of current life forms on Earth.
Recent analysis has shown that these are not simple organisms. In fact, the original name of these organisms, ‘algae,’ is deceptive and implies a simplicity that is not a part of these organisms. They are not algae, they are bacteria. Their life processes are every bit as complex as the life processes of the extremely complex DNA-based life forms in our world today, including human beings.
When the first cyanobacteria came to exist on this world, it was a very hostile place. It had no oxygen in its atmosphere at all and had a very high level of carbon dioxide. Carbon dioxide traps heat. In part because of the high carbon dioxide level that trapped the heat, and in part because the Earth was still in the process of cooling from its initial temperature of several thousand degrees (when it was still forming), the Earth was very hot.
It is important to understand how we know that oxygen did not exist in the early Earth atmosphere, so I need to diverge a little and go over some chemistry:
Oxygen has very powerful bonding properties. If you put oxygen in with silicon, iron, aluminum, or just about any other element, the element will attract the oxygen and the oxygen will bind with it. The most abundant material in the Earth’s crust is silicon. This silicon is now found mixed with oxygen. It is ‘silicon dioxide,’ the chemical name for the most abundant material in ‘sand and rocks.’ Carbon binds with oxygen with very powerful bonds, into carbon dioxide. If both carbon and oxygen were in the atmosphere, the slightest bit of heat or electricity would cause them to ‘burn’ to form carbon dioxide. If any oxygen survived, it would be sucked out of the air by the silicon, aluminum, iron, or other elements of the Earth’s crust and would be bound into these elements. If you want to do an experiment to see this happen, you can leave some iron out in the open air. A few days later, you will see reddish brown dust form on the surface. This is iron oxide, the chemical name for ‘rust.’ The iron has sucked oxygen out of the air and bound it with the iron.
Cyanobacteria contain the protein ‘chlorophyll’ which takes advantage of solar energy to go through a process called ‘photosynthesis.’ In this process, carbon and oxygen are split apart. The oxygen is released into the air as unbound or ‘free’ oxygen. The carbon is put together with hydrogen (made by splitting water, or H2O, into hydrogen and oxygen) and becomes a part of the bodies of the cyanobacteria. The very first cyanobacteria used this process to take carbon dioxide out of the air and replace it with oxygen. Its descendents did the same thing.
At first, the oxygen added didn’t cause any significant increase in the oxygen level because of the high reactivity of oxygen. The silicon, aluminum, iron, and other elements of the Earth’s crust soaked up the excess oxygen. These elements soaked up all of the excess oxygen the cyanobacteria produced for the first 1.18 billion years that these life forms existed. The oxygen level of the atmosphere remained at zero, or so close to zero that any difference isn’t important for practical purposes, for this entire time.
The carbon that had been bound with the oxygen didn’t just disappear. The process of photosynthesis causes this carbon to form into chains, mixed with hydrogen. These chains of carbon and hydrogen have two different names. Biologists call them ‘carbohydrates.’ Geologists call them ‘hydrocarbons.’ Although these names are different, the two terms refer to the exact same molecules. Practitioners in the respective fields call any molecules that are chains of carbon and hydrogen both of these things.
The carbohydrates become a part of the bodies of the cyanobacteria. When the bacteria die, they settle to the bottom of the body of water where they lived and are covered. Over time, they get covered to great depths, creating great pressure. This causes the hydrocarbons to turn into coal, oil, or natural gas. It becomes fossil fuels. From the time that the first cyanobacteria lived on Earth, hydrocarbons (fossil fuels) were being formed. By the time 1.18 billion years had passed, immense amounts of hydrocarbons were buried under layers of sediment. Although incredible amounts of oxygen had been removed from the carbon dioxide in the atmosphere, the oxygen levels had not yet begun to rise, because this oxygen was being soaked into the silicon, aluminum, iron, and other materials that the crust of the Earth is made of. But by the end if 1.18 billion years, these materials had soaked up all of the oxygen they could hold and the atmospheric oxygen levels began to rise.
They rose steadily over the next 1.9 billion years until they reached about 21% roughly 567 million years ago.
Why Oxygen Levels Matters
Schools teach that fossil fuels come from decaying dinosaurs. This is not correct. By the time complex organisms like dinosaurs existed, all of the carbon that is now under the ground was already under the ground. The coal, oil, and gas were created during the roughly 3 billion year period before complex life forms like dinosaurs existed.
The changes that these early beings made to the atmosphere did two things that helped make complex life possible:
First, they created the ‘unbound’ oxygen that is needed for the highly efficient organisms that live now.
Oxygen-using living things depend on a process called the Krebs cycle, described below, to create energy. The Krebs cycle is incredibly efficient; it is roughly 30 times more efficient than the process used by living things that do not use free oxygen (called anaerobic beings) use. All complex living things use oxygen. They require the ‘free’ or ‘unbound’ oxygen that now exists in the atmosphere for their life processes. Without atmospheric ‘free’ oxygen, they die. We are complex living things. Without oxygen, we die. If the oxygen had never existed, the complex life forms that depend it now, including humans, would have never come to exist either. We are here because of the free or unbound oxygen created by the cyanobacteria. Our world is as it is because of this oxygen.
When the world first formed, there was no free oxygen at all. When the first cyanobacteria appeared, there was no unbound oxygen either. The first 1.18 billion years of the era of life, oxygen was created by photosynthesis but not in high enough quantities to cause the Earth’s atmosphere to have any measurable free oxygen. The first measurable free oxygen came to exist about 2.4 billion years ago. The atmospheric oxygen levels didn’t reach 5% until about 1 billion years ago. Although this was a lot more oxygen than had existed before, it still wasn’t enough to support complex life forms. The oxygen levels increased. They finally reached a level that could support complex life forms, about 20% of the atmosphere, 521 million years ago.
At this point, an incredible transition took place on Earth. Scientists call the period that began 521 million years ago the ‘Cambrian period.’
A Transition Between Life Forms
As soon as the Earth had the necessary conditions, the living things suddenly started to ‘act’ differently, almost as if they had a different purpose:
First, for some reason that no one today seems to understand, oxygen-using life forms suddenly materialized. As we will see shortly, all aerobic beings on earth use oxygen to generate the energy these beings use to support their life processes. Before the Cambrian period, there were either no aerobic beings on Earth or so few of them that they didn’t leave any record of their existence that we can find today. As soon as the oxygen levels were high enough, these living things appeared and quickly grew to extremely high population levels. Since these living things used the oxygen that the cyanobacteria produced, converting it back to carbon dioxide, the oxygen levels stopped increasing. All of the excess oxygen that photosynthesis created was turned back into carbon dioxide by the living things.
Sex
Another change that took place 521 million years ago involved sexual reproduction. The cyanobacteria reproduced by a very simple process that basically made exact copies of the original beings. This process is called ‘mitosis.’ The ‘code copying’ mechanism of mitosis is extremely accurate and mutations are extremely rare. If there are no mutations, there is no evolution. Every being is the same as the one before it. The old beings reproduced using a process called 'mitosis,' one that produces exact copies with incredible precision. There were virtually no mutations.
The new beings began to reproduce using a process that mixed the DNA of two parent cells to create an ‘offspring’ cell that combined the DNA of the ‘parent’ cells. The offspring was not identical to either of the parents. In fact, the offspring wouldn’t even have to be similar to either of the parents; it would be a mixture of the two genetic structures that would basically be unique. The offspring cell would have a genetic structure that had never existed before.
In non-sexual reproduction, mutations are normally bad: they harm the ability of the organisms to survive. Sex changes this. It allows enormous variety. Some of the offspring had characteristics that made them more capable than other offspring. They would survive to reproduce. They would reproduce with other offspring that also had advantages, mixing their DNA to create new offspring that would have the advantages of both parents.
These new offspring competed with the less-capable beings for resources, and won. They survived to pass their advantages on to their offspring, leading to a process of evolution.
This process is extremely rapid in beings that reproduce sexually. You can tell this if you have ever bred plants or animals intentionally. Within only a few generations, you can create totally different varieties and breeds.
Somehow, once the oxygen was there and temperatures were suitable, the living things ‘found out’ about this and changed their nature. Evolution took place at a fantastic rate. Within a very short period of time after oxygen arrived, some 521 million years (short in geological time), we were here.