Month: December 2020

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Evolution: Refuting Poor Arguments Against It

Evolution: How It Works

Christian Arguments

All of the arguments I bring up here are actual arguments I have encountered myself when talking to my parents or other Christians. Here are the arguments they tend to make arranged by how often they are made (I made up Latin-ish names for 6 of them).

  1. Argumentum ad absurdum (Argument from Absurdity)
  2. Argumentum ad auctoritate (Argument from Authority)
  3. Argumentum ad populum (Argument from Popularity)
  4. Argumentum ad theorium (Argument from Theory)
  5. Argumentum ad Noahsium (Argument from Noah)
  6. Argumentum ad tempore (Argument from Time)
  7. Argumentum ad fossils (Argument from Fossils)
  8. Argumentum ad abiogenesis (Argument from Abiogenesis)
  9. Argumentum ad grandeur (Argument from Grandeur)

Evolution is Absurd!
(Argument from absurdity)

The primary argument I encounter when talking about evolution with my parents is an attempt to show that evolution is absurd. To adequately argue that something is absurd requires first showing that you understand the contrary viewpoint by honestly representing it. No Christian I have talked to has ever honestly shown that they understand evolution properly (not to say one doesn’t exist, just that I personally haven’t met one yet).

When I talk to Christians about evolution, they are unable to demonstrate an understanding of how evolution works, they merely assume the idea is absurd and then come up with absurd examples to fit their absurd assumption. To quote one person I was talking to, she said “…you believe that suddenly ‘shoop‘, there’s an ear just sitting there. What use is that?” This is a fundamental misunderstanding of how evolution works, which I’ve often seen to be a lack of education on the topic or being motivated by a desire to fit their religious narrative onto reality.

Ironically, if any instance of this happening was ever observed, it would immediately disprove evolution rather than prove it correct. Evolution works through gradual changes over time, not miraculous leaps. Arguments like these demonstrate a profound misunderstanding of how evolution works by creating a a straw man to easily chop down. This is harmful to both parties in a discussion. Rather than driving the person with less knowledge to understand how evolution does work, it reinforces their preexisting beliefs about the absurdity of evolution. Conversely, it makes the person who has spent months, or possibly years, learning biology feel angry at the (perceived) willful ignorance of the person they’re talking to.

To give a very brief explanation, evolution is the explanation of how the diversity of life has exploded since life first began. How traits are inherited by children is well understood, and genetics has made significant advances in understanding and treating diseases that are inherited. Altering the DNA of living creatures can show an immediate change in behavior or cause traits to change or appear. There is no doubt that DNA is the process through which traits are inherited nor any doubt that it takes a long long time.

To address the ear claim from above here, keep in mind that evolution requires a long time to work. An ear is not going to suddenly just appear out of the blue. It IS possible that a group of cells might have a mutation to relay very simple auditory information to those around them. As the years progress, and the species reproduces, the ability to process this auditory information becomes useful and actively aides in the survival of the organism. Because it aides the organism, mutations that make the process more efficient and reliable begin to help the organism survive better. Millions of years later, there might very well be a fully formed ear on an organism. It’s almost certainly not the same organism (or organ) that the process began with, however.

My Holy Book (or Preacher) Says Evolution is Wrong!
(Argument from authority)

The next most common claim I get is that some authority says evolution is wrong. Because this authority says evolution is wrong, then evolution is wrong.

Unfortunately for the person making this claim, there is often no reason to believe that particular authority is a good source of information on the subject. Because I live in a Christian dominated section of the world, I’ll specifically use the bible and pastors/preachers as examples here.

In the case of the bible, the people writing it had no understanding of evolution. While they incorporated the best science available to them at the time when the Jewish people were held captive by the Babylonians, the breadth of knowledge about the world they had was still very small compared to today. The Babylonians pioneered things we consider pseudoscience today, and some of these things became enshrined in the bible. For example, astrology, which is mentioned in Genesis, has no basis in reality.

Additionally, the bible does not teach science or rational query of the world. For example, this is seen in the story of Noah and his ark. Since the focus is evolution here, it’s clear that the authors had no true understanding of the amount/diversity of life and the size of the planet they lived on. While Noah’s ark IS a large boat, it is absurd to think that any appreciable amount of the billions of species on earth could sustainably fit into such a (comparatively tiny) space.

Specifically for biblical literalists, a favorite is to say that the bible says life was created by god. This is, of course, the same as the previous argument. I’m merely going to examine the primary reason that people point to the bible as evidence – Genesis chapters 1 and 2.

Let’s put aside the problems and contradictions within these 2 separate creation myths (they tell different, but similar stories). The story immediately invokes a supernatural creator and all questions about it are resolved with “It was god!”. There is no verifiable evidence for the stories – finding Eden would be a nice start – nor is there any way to test that creation really happened. There are ways to test whether or not creation is a good explanation for lie however.

As one example, if all life was created in specific forms, we would expect their forms and internals to be uniquely distinct. For example, the nerve and blood vessel structure that bests suits a fish would probably not be a very good structure for a fast-moving land animal. Despite that, we see artifacts from a shared ancestry that still persist despite the form of the creature varying wildly. For example, Vertebrates all have a Recurring Laryngeal Nerve. On a fish, this path is a relatively short path from the jaw to the throat with a brief detour around internal organs (specifically the heart). Taken to the extreme on land, the Giraffe has a Recurrent Laryngeal Nerve of over 5 meters long (from it’s jaw, looping past the heart, back up to the throat). While these inefficiencies are exactly what we would expect to see in organisms that have evolved from a common ancestor, we would not expect to see these sorts of inefficiencies in designed creatures.

Similar problems apply to believing the words of preachers or pastors. Preachers are people who have often gone to seminary school and believe the religion they are in. There is no requirement to take scientific classes to receive an MD (Masters of Divinity) from seminary schools. Despite this lack of a scientific background, many preachers will talk passionately and authoritatively on scientific subjects that they have no experience with. While possibly unintentionally, they will end up misleading the people who trust them to tell the truth on topics. Oftentimes they will cite the bible as their source, which simply pushes the authority of the claim back to the bible. As already mentioned, the bible is not a scientific source.

To clarify, I’m not saying all Christians use or believe this, but most that I have met do. For example, non-literal interpretations of the bible often allows leeway for a scientific/naturalistic explanations of events.

But Many People Don’t Believe in Evolution!
(Argument from Popularity)

The argument from popularity can be summed up as “A lot of people believe this, therefore this thing is correct.” Unfortunately, arguing against evolution from popularity is one of the weakest arguments that can be made, but it is made often. The people who don’t believe evolution occurs often do so because of their authority figures telling them it is wrong, lack of education, or lack of desire to explore evolution at all. The reasons someone could disbelieve evolution are many and varied. In the end, the whys don’t matter. The amount of people who disbelieve in something is not evidence in and of itself.

To reiterate plainly, popularity is not evidence. The site dissentfromdarwin.org has created a list of about 880 signatures in total of scientists who agree with the statement “We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged.” That may seem like a large number, but consider the response of the National Center for Science Education. They created a list of scientists named Steve (Archive Link) (or variations such as Steven, Stephen, etc) who believe evolution occurs, and currently has over 1500 signatures of Stevens on their list as of 2025-02-01.

The amount of “Stevens” in the world who believe evolution occurs outnumber the creationist list, and the amount of Steves in academia is estimated to be about 1% of the total population. While funny, all it proves is that a lot of people named Steven think evolution is True. The same can be said for the creationist list; all it proves is that 900-ish people don’t think this is true. Neither list proves anything positive or negative about evolution. That’s what evidence for or against evolution is for.

There are a variety of reasons that someone may believe or disbelieve in evolution, but the popularity of the opinion should not be the reason for their belief. Hearing that many people disbelieve evolution – such as through the creation and dissemination of large lists lists – is doesn’t contribute to the scientific community at large and manufactures a feeling of extreme controversy. Rather than controversy, the scientific community is surprisingly well united, with those who dissent usually having qualms with the specific mechanisms of evolution rather than whether it occurs at all.

But Evolution is Just a Theory!
(Argument from Theory)

Many people misunderstand just how concrete, specific, and definite a well accepted theory in science is. When they argue this way, they almost always use the exact phrase “But evolution is just a theory” or “That’s just a theory”. This is because in common parlance, a “theory” is more akin to an educated guess (more formally known as a hypothesis), wild speculation, or hunch.

This is often done to make scientific theories seem like a simple guess. The reasoning for this is clear: a simple guess is not a good way to try understand the world. This usually ends with the theory being discussed appearing to be discounted as valid. There are a few problems with this viewpoint though.

First, and most importantly, a scientific theory is far more than a simple guess. A scientific theory has the weight of observations, facts, and experimental results contributing to it along with an explanation of how they relate. A theory that has particularly good explanatory power receives scientific consensus when, after much testing and experimentation, the majority agree it’s the best explanation for now. Theories tend to be tested often even after scientific consensus since a new understanding of something fundamental to the field could overturn the theory.

In Evolution’s case, these are some of the facts

  1. Children resemble their parents
  2. DNA is the method of genetic transfer
  3. The skeletal structure of vertebrates is similar throughout many species
  4. All living things are composed of cells (Cell Theory)

Note that last one: It too is a theory, just not one that is attacked nowadays. There are certainly many more facts that could be added, but I’m keeping this section intentionally brief. All these facts taken together along with an explanation of how they relate constitute a theory.

Here are a few other “just theories” to how how diverse theories can be.

  1. Gravitational Theory
  2. Atomic Theory
  3. Germ Theory of Disease
  4. Attachment Theory

But the Flood (and Noah’s Ark)!
(Argument from Noahsium)

This is similar to arguing from authority via the bible. I made it a separate argument because many people I talk to don’t see it as the same argument. Those same people often find this argument highly compelling.

For those who don’t know, in Genesis, there is a tale about how a man named Noah gathered up 2 of every “kind” of animal (ignoring insects, arthropods, fish, etc) on the planet and took them on a boat for several months while the earth was completely flooded and underwater (including all mountains such as Mt. Everest). A flood of this magnitude would have evidence for it all over the place. As one example, there would be evidence of a global devastation of life due to flooding. While there is a lot of evidence for mass die-offs from many sources, evidence for a worldwide flood has yet to be found.

I’m not going to focus on whether or not a god could miraculously make this happen – saying “god did it” does not offer an explanation. I don’t particularly want to focus on the geographic distribution of fossils, flood plains, young earth, or other common rebuttals here in this section. Those have been covered far more comprehensively than I could ever do here. Instead, let’s focus on the consequences of a large scale flood as described in the bible.

  1. Literally kills everything
    • Animals would die off from lack of food
    • Fish would die off from incorrect saline content (freshwater and saltwater alike)
    • Plants would suffocate and die (Yes, they breathe in a sense and can’t live underwater)
    • Saltwater plants would die from the mixing saline/freshwater content
  2. Noah’s ark would encounter issues as waters rise
    • Inability to restock food would kill everything onboard
    • Inability to breathe when waters rise too high (oxygen thins out as you get higher)
    • The boat would freeze over as the waters rise (it gets COLD at Mt. Everest height!)
  3. Assuming the ark somehow makes it back, everything is dead
    • No, that dove would not find a living tree to get an olive branch from
  4. Two of every creature is not enough to repopulate the planet
    • Predators would quickly eat the prey, and then probably eat the humans
    • Herbivores would die out from lack of food
    • Humans would die out from lack of food
    • Even assuming reproduction happens (somehow), genetic disease due to inbreeding would run rampant
  5. No place for the water to go after the flood
    • This is “explained” in the bible by referencing an outdated and incorrect biblical flat-earth model where the earth is drained.
    • There is no natural mechanism we know of that could drain such a large amount of water.

A global flood of biblical proportions is a literal end to all macro-life on the planet. Some extremophiles might survive on the ocean floor – bacteria and other microscopic organisms – but large multicellular, macroscopic creatures would almost certainly be extinct. Simply put, a global flood of biblical proportions would have left no room for the survival of life as we know it, and there is no credible evidence that such an event ever occurred

But the Earth is 6,000 Years Old!
(Argument from Time)

Young earth creationists tend to hold the viewpoint that the earth is about 6000-10000 years old, and that the flood happened sometime in the past 4-6000 years. As an upper bound, this gives 6000 years. If creationism could be shown to be true, then this claim could possibly be justified, especially since a young earth is used an attempt to argue that not enough time has passed for evolution to work as described by evolutionary theory as well.

Unfortunately for young earth creationists, Carbon Dating is a reliable method for dating objects to 20,000-50,000 years ago. After that point, the amount of carbon content becomes too small and Carbon Dating gives wildly inaccurate results. Given that this method alone can produce evidence for an earth at minimum 20,000 years old, the hypothesis that the earth is 6,000-10,000 years old is disproven as soon as it’s uttered. Carbon dating may not tell us how old the earth is, but it can tell us that creationists are off by several thousand years at least.

Because of the inability of carbon dating to determine ages older than 20-50k years reliably, young earth creationists often attack radiocarbon dating as wholly unreliable. Often, they claim that it’s highly inaccurate and often gives incorrect answers all the time – not just when things are older than 20-50k years or when it is misused to date items without carbon in it. Even if we assume they are correct about carbon dating, there are other techniques that are accurate to larger timescales.

As another example, radiometric dating is based on the half life of radioactive elements which take a very, very long time to decay. This decay rate is well measured and understood, and has been used to measure the age of the earth to billions of years. Because of it’s accuracy, radiometric dating is commonly used to date rocks in Geology today, leading to an earth of around 4-4.5 billion years of age.

One other point bears mention here, another direct quote from a conversation I’ve had with a young earth creationist. She told me “Scientists keep adding on more and more time because evolution just doesn’t work out. You know, just add a couple million years here, a couple million years there, and then they say it works.”

The is a misapplication of logic by putting the cart before the horse. Scientists don’t keep adding time to their estimates to make them work out. They have a hard limit to work with. The age of the earth is well known and supported by evidence, and the claims made by evolutionists work reasonably well within that time frame. There is a well documented and peer reviewed timeline of life that can be viewed, and evolution works within that timeline for the earth. Radiometric dating of fossils can be used to date when those creatures lived and what creatures were around at that time, and fossil records provide a record to verify against. All of the evidence supports an earth that is really old, not merely several thousand years old posited by young earth creationists.

But We Don’t Have All The Fossils!
(Argument from Fossils)

Creationists seem to make a lot of claims about fossils. These include (but by no means are limited to)

  1. The fossil record was faked by god or satan
  2. Fossils were all mixed together by the flood
  3. We’re missing transitional fossils

Claiming that fossils were placed there by god or satan is impossible to test or falsify. Without any evidence for this, there is no justification for this claim or reason to really rebut it. I’m not going to examine that argument further here, even if the idea of either god or satan being enough of a joker to place fossils around as a cosmic prank to mislead people does amuse me. Instead, let’s look at how fossils form.

Fossils have several different methods.

  1. Permineralisation where mineral-rich water fills up cell walls and evaporates, leaving a mineral deposit in the shape of the material it replaces
  2. Impression – A buried organism gradually decomposes while the earth around it hardens into a hard shell leaving an empty space where the organism was
  3. Casts – A buried organism fills up with minerals. The organic components decompose, but leaves a fossil in the shape of the organism
  4. Amber – Organisms trapped in tree resin can become preserved
  5. Trace Fossils – Fossils that indicate organism activity, such as footprints, nests, burrows, etc
  6. Soft Tissue – Tissue can be rarely preserved if the fossilization process somehow prevents complete decomposition, such as within ice or volcanic ash.

Central to all of these is a large component of time. The dead organism needs to spend a long time in one place in order for a fossil to form. This leads to the organism slowly being buried via natural geologic processes over time. For example, an organism that is covered in volcanic ash will slowly be covered by dirt as time goes on. This gradual covering of an organism over years, decades, and centuries leads to a concept known as the geologic column.

The geologic column can be through of as a record of what the earth was like at a certain time. This column can be imagined to be organized into rows that indicate how old the layer is. The criteria to find an old layer is generally pretty simple: Simply dig deeper. As you dig deeper, you will be traveling backwards through time to peer into what the earth’s surface looked like many years ago.

To tie the column and fossils together, fossils become part of the geologic column. They don’t do this intentionally, rather, they get covered over many years and become integrated into the geologic column for the time period it was a part of. This means that fossils are generally arranged in the same order as the rows in the geologic column: oldest at the bottom.

Now that we understand how fossils form, we can now examine why the flood mixing fossils doesn’t hold up to scrutiny. Even if a flood did occur on the scale mentioned in the bible, fossils that had been buried for hundreds, thousands, or even millions of years, would remain undisturbed. If there was any evidence of a flood mixing fossils, the mix would occur in a single layer, and it would probably show a large amount of fossilization compared to other layers due to the large amount of water and relative lack of creatures eating the decaying organisms.

Finally, let’s examine transitional species and their fossils. Transitional species are those species that provide a link between and older species – one that may have long gone extinct – and an ancestor species. This species showcases common traits from it’s ancestors, and it’s later descendants. For example, Archaeopteryx shows traits common to it’s dinosaur ancestors and traits similar to it’s descendants, the modern birds.

Creationists often claim that we don’t have transitional species fossils. They further reason that since we don’t have those fossils, there’s no evidence to show the gradual change over time that evolution claims would happen. And therefore, because there is no evidence, evolution must be false, and god created everything.

Most of the time, this argument is based off of some incorrect assumptions and incomplete knowledge. First, we do have a large list of transitional species. Second, evolution still holds true even if we can’t find every single transitional fossil. All that is required is enough fossils to show a clear line of ancestry.

Fossilization is a relatively rare process, and it’s unlikely that we will ever find fossils for every transitional species. However, more than enough transitional fossils have been found to prove that transitional forms did exist.

Evolution Means Life Would Come From Nothing!
(Argument from Abiogenesis)

Evolution makes no claim for how life started (that is known as abiogenesis). There are many other hypothesis and experiments that look into this, but evolution doesn’t adadress how life began. Evolution is an explanation for how life changed (and continues to change) over time once life originated.

There are several hypothesis for Abiogenesis, but the area is still an active subject of scientific inquiry. I’d recommend reading through the Wikipedia article for more information on Abiogenesis if you are curious to learn more about this topic since it is a very complex topic as well!

Evolution Can’t Be Real, We’re So Much More Than That!
(Argument from Grandeur)

Christianity places humans central to the creation story by having humans made with all the other animals by the literal creator of everything. The creator then spends a large amount of time on these first humans, making sure that they are well taken care of and places them above all the animals. This human-centered view continues to shape how many Christians perceive evolution.

Many Christians I have talked to view evolution as somehow degrading, as if being “mere animals” is an insult to consider. Unfortunately for these Christians, finding something degrading doesn’t take away from the truth of it. If anything, evolution offers a more grand perspective on humanity. After all, if we consider Genesis 2, humans made from dirt might actually be less noble than being mere animals.

Discounting evolution as being an ignoble beginning to the human species completely misses the mark. If creationist want grandeur, then Evolution has all the grandeur and splendor they could ever ask for. From an evolutionary perspective, humans are a huge success story. Far from being lowly, Humans are standing on the shoulders of billions of years of evolutionary history that conferred a little more intelligence on the ancestor of the human species. With our increased intelligence, we humans have dominated the planet and are now beginning to learn how the universe itself might work. Who knows what we might accomplish in the future?

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Evolution: How It Works

Evolution: How Science Works

Evolution: Refuting Poor Arguments

Now that a basic understanding of how the scientific process works, let’s look at how the Theory of Evolution (yes, it deserves that capital T) works. Because I’d like to be somewhat comprehensive, I’m going to start small and work my way up. Because I consider a lot of this to be common knowledge, and because Wikipedia does a good enough job of explaining the things linked, I’ll probably mostly cite Wikipedia here.

Also, for an excellent lecture series by the renowned evolutionary biologist Richard Dawkins, see here (Or here for a playlist including them if youtube has pulled them or you have trouble getting to youtube). He explains things far better and more eloquently than I ever could without many more years of studying.

Evolution

For evolution to occur, several distinct things must be true.

  1. There must be traits that are Heritable
  2. There must be a mechanism for Heritability
  3. It must be possible for Mutations to occur (Heritability is not 100% perfect all the time).

With these simple premises, the basics of how evolution works can be explained in a short paper. Do note that I’m going to focus on getting a broad overview of how evolution works rather than every individual detail. Things will be left out in order to get the point across in a timely fashion. For example, I’m not going to cover social or sexual selection because most people either 1) Don’t know about them, or 2) are not talking about social and sexual selective pressures when they bring up evolution in a typical conversation.

Heritability

Before digging deeper into the small details of evolution, a case for heritability must be made. To say that a something is heritable is to say that the offspring resemble the parents to some degree.

The fact that offspring inherit traits from their parents was first rigorously tested by Gregor Mendel in 1822[1]. Gregor did experiments with peas and demonstrated that there is a correlation between what traits the offspring of crossbreeding certain plants have.

Picture some large family you know. Think about the natural hair colors of the children and the parents. Unless one of them is adopted, born with another parent, or has a mutation changing their hair color (it can happen), they will generally be similar. For example, in my family, the predominant colors are brown, dark brown, or blond.

This single observation forms the basis heritability. You can look anywhere to find this. Tabby cats bred with other tabby cats will have tabby kittens. Brown cows bred with other brown cows have other brown cows. The offspring are similar to their parents.

Taking a closer look at large populations of animals or people, you’ll notice that some traits tend to be more common than others. With some families, you might notice that the children have brown eyes despite one parent being brown eyed while the other is green. These traits that are more common are called Dominant Traits, and tend to “override” traits that are not (aka: Recessive).

This simple observation gives rise to a simple probabilistic method of examining heritability known as a Punnett square. While not a perfect example of how heritability works, it lets you make probabilistic predictions on what traits the children will have based on what the parents have.

At this point, it would be natural to wonder if you could test this somehow. For example, could you breed animals for a particular trait, such as coat coloration or size? The answer is yes. It wouldn’t be hard to do, although it may take longer than your lifetime to see the results depending on the animal. Just make sure the animals with the traits you like breed together while discouraging the others from breeding.

To use dogs as an example, repeat this for hundreds of generations selecting for small size and long body, and you might get a dog similar to a chihuahua. Go the other direction and select for large size, and you might get something similar to a great dane.

While this sort of thought experiment is easy to do – and in some cases, physical experimentation may be easy – it still requires some way for all this to work. If offspring resemble their parents, then how is that information about the parent transferred to the offspring? Without a mechanism through which to transfer these traits, there is no way to truly experiment and determine what causes these traits. Thankfully, a mechanism was discovered in 1869 – within a decade of Darwin publishing “On the Origin of Species”.

DNA and Cells

It is a well known scientific fact that Deoxyribonucleic Acid (DNA) exists[2] which affords us with many applications. To name just four from memory, there are

  1. DNA profiling in forensics
  2. DNA Paternity Tests
  3. Ancestry/Ethnicity tests
  4. CRISPR Editing

DNA is a protein found in all living organisms, the smallest of which are single-celled organisms and viruses (although there’s a great divide on whether or not viruses are alive). Cells use DNA as a “blueprint” to build the proteins required for the cell to function. The DNA is responsible for what shape the cell will be, how the cell interacts with the world around it… in short, everything that makes that cell. As the cell lives, it slowly increases in size until it becomes difficult for the cell to sustain itself. At this point, the cell usually divides into 2 different cells.

As part of this split[3], the cell makes a copy of it’s genetic material and then and gives half to one of the new cells, half to the other. To make this copy, the DNA is opened up and each half of the DNA is copied one at a time. Most of the time, the copy happens without issue and each cell gets an exact copy of the DNA.

Errors when copying the genetic material, known as mutations[4], are generally benign and cause no problems or bestow no benefit. Occasionally, however, mutations can cause changes in how the new cell looks or functions. This change in look or function could be positive or negative, an error in copying DNA the benefits a cell is still an error in copying. If the mutation causes the cell to function less efficiently, then it will die out over time. If the error confers an advantage to the cell, then it will grow better or find/consume more resources. Because it does a better job than it’s peers, it will be able to divide more often and will eventually take over it’s little niche. This is often called “Survival of the Fittest”, although a more appropriate term is “Reproduction of the Fittest”, as we’ll see later.

Cellular Origins

Evolution can adequately explain how life slowly changes from one form to the next when provided with a single cell containing heritable genetic code. Variations in DNA, the genetic code of the cell can cause it to be more or less efficient at what it does. As the cells who happened to get the not-useful or outright fatal mutations die out, the cells with useful mutations dominate. As the cells become more specialized in a particular environment, they become more and more different from their predecessors. This causes different types of cells to emerge.

As these specialized cells move into new environments, the process repeats again and again. This causes more variation in the cells and further changes to live in novel environments. When a cell has become so different from it’s progenitor, or from other cells around it, that it can no longer be considered the same type of cell, it is considered to be a new species.

Multi-Cellular Life

If mutations can explain how single celled organisms change their behavior and adapt to new environments, then how did multi-cellular life like humans arise? As you might expect, mutations in the genetic code offers an explanation as well.

Mutations can also affect how cells act towards other cells. If a cell has a mutation that changes it’s behavior with other cells to more cooperative behavior rather than competitive, cells could begin to group together. Now that a group is forming, mutations that help the group survive are also help the individual cell survive. As such mutations occur, the group becomes stronger as a whole. At some point, the cells end up as a single cooperative unit that is able to support itself.

Implications of a Shared Origin

Because an Evolutionist view of how life started requires just a single cell, there are several things that are cell specific we should see when we observe other life on our planet.

  1. That life should be composed of cells
  2. Those cells should contain DNA
  3. Those cells should contain similar (not 100% the same) structure
  4. The DNA in cells from different species should contain some similarities

The first three points are readily observable by anyone. Just take a mouth swap of yourself and a few other animals and look at the cells under a microscope. The fourth one, while not so easily observed, has also been shown by scientists who found more than a 40% DNA similarity between humans and bananas. These similarities are some observational evidence that indicate a shared origin.

In addition to evidence provided by DNA, there are other similarities we should see on a macro level when we observe the diverse life forms around us. If we all truly share a common origin, we should be able to find at minimum the following things (I’m sure there are more)

  1. Find relations between life and categorize it
  2. Determine when species branched off from each other
  3. Find similarities in anatomy between species such as humans and whales
  4. Find remains of long-dead animals that show relations between species

As the links may indicate to you, all those and more have been done.

Evolution on a Macro Level

Traits

The method for passing on traits to children are bundles of DNA known as Chromosomes that contain Genes (specific sequences of DNA). If the child has the same gene as their parent, they will have the same traits as the parent. There are many traits that can be passed on. Humans, for example, could pass on their eye-color trait. If both parents have the same colored eyes, then it’s highly likely that their child will have the same colored eyes as well.

The fact that genes are DNA sequences means the same issues affecting cell division apply here. The genes may not be copied correctly, and when offspring are made, the offspring has a gene that is slightly different. Again, like in cells, this may be beneficial, harmful, or cause no change at all.

Much like the cells they are made of, the animals most suited to their environment live healthier lives and reproduce more. This causes the traits of those best suited to their environment to flourish throughout the population and those traits that are harmful to decline. An example of this is lactose (in)tolerance[5]. In regions where dairy products are heavily consumed, larger portions of the population retain the lactase enzyme through to adulthood.

Larger changes, such as changes to the species’ form or coloration, come about the same way. If a slight change in form or color helps the species pass on more of it’s genes, then those genes will slowly pass on through the population until most or all of that species has the trait.

The most important thing to remember here is that trait’s will slowly move through the population so long as it allows the organism to reproduce more often. This is often incorrectly called “survival of the fittest”. While survival is certainly necessary in order to pass on genes, having an adaption that allows an organism to live a year longer, get more food, and reproduce one or two times more than the others will spread the gene slowly through the population.

Conclusion

While this overview may not be a complete explanation of how evolution works, I hope it helps in leveling the playing field when it comes to talking about evolution. Most religious folks that I talk to (primarily Christians where I live) don’t know the basics of how evolution works. They discount the theory entirely merely because their religious authorities tell them that it’s wrong. Because there are some arguments that show up time and time again, I’ll be covering ten of those next.

Citations

  1. https://www.britannica.com/biography/Gregor-Mendel
  2. https://en.wikipedia.org/wiki/DNA
  3. https://en.wikipedia.org/wiki/Mutation
  4. https://en.wikipedia.org/wiki/Cell_cycle
  5. https://web.archive.org/web/20200929193711/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3048992/pdf/rstb20100268.pdf
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Evolution: How Science Works

Evolution: It’s Not a Debate

Evolution: How Evolution Works

The Scientific Method

Many people may remember the scientific method from their science classes. If it’s been a while for you, it goes something like this.

  1. Make an Observation
  2. Ask a Question about what you Observed
  3. Research for existing answers or solutions to that question
  4. If you find no existing answers or solutions, form a hypothesis about what happened
  5. Do an experiment to test your hypothesis
  6. Accept, reject, or revise your hypothesis based on your test results
  7. Draw conclusions based on the hypothesis and test results
  8. Repeat steps 4-7 as many times as needed
  9. Report and share your findings

This is pretty straightforward. You see something and you wonder why it happens. If you find no well tested answers, you try to figure out what causes it by running experiments until you figure out the root cause. Once you can reliably repeat your experiment to demonstrate the cause, you then share your results.

Everyone does this to some extent going throughout their day. For example, say you notice that Carl is angry, and you wonder if he had a bad night’s rest. You’ve just completed steps 1-2 and are about to proceed to step 3/4/5 (they’re a little tied together in this case) by asking Carl what has him so riled up today. You then accept or reject you hypothesis (that Carl had a bad night’s sleep) depending on what he tells you. If you wanted to repeat the test, you could ask him a couple times and see if the results are the same.

While there is obviously more to the intricacies of science, such as creating good tests, vetting trustworthy sources, and understanding your field well, going into those would take far too much time. If you want to look into it more, then here is a good start. Let’s look at a few terms that are often misused before moving on.

Hypotheses, Facts, Laws, and Theories

Science boils down to four things: Hypotheses, Facts, Laws, and Theories. They are usually related in some way. For example, a law about a phenomenon could be discovered. Shortly thereafter, a hypothesis about a fact based on the discovered law could be made followed by the results of an experiment that confirms the fact. When you start tying together really in depth explanations of how something works, that’s when you get a theory. Let’s look at these more in depth.

Hypotheses

Hypothesis – a proposition, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either asserted merely as a provisional conjecture to guide investigation (working hypothesis ) or accepted as highly probable in the light of established facts. Plural: Hypotheses

Dictionary Definition of Hypothesis

A hypothesis is the initial exploratory explanation of an observation that has not yet been proven true or false. This the best guess that needs testing in order to determine if it is true or false. Depending on how the testing goes, the hypothesis could be revised, rewritten, or completely thrown out dozens or even hundreds of times.

Until the person making a claim can show that the hypothesis is indeed a good explanation for the data, and is unable to prove their explanation false, it needs to be continually tested. When the person making the claim believes their claim to be true, and their tests bear out that result, then they have others also test the claim. If even one person finds a problem with the hypothesis, it will often need to be modified even more until it becomes a good explanation for the phenomenon. Confirming and failing to refute, or refuting and failing to confirm, a hypothesis can lead to new facts or laws.

Facts

A scientific fact is an observation that has been proven to be true and has often withstood many attempts to prove it wrong. That doesn’t mean it can’t be proven wrong, nor does it mean it won’t be proven wrong in the future. It merely means that to the best of our abilities right now, the fact appears to be true and can be treated as such. Laws and Theories often build upon facts to give explanations of why those facts are true.

Laws

If the explanation of the phenomenon can be described with a mathematical relationship, such as Newton’s law of Gravitational Attraction, it’s considered a law. These laws are like tools in a tool box that allow the user to predict what would happen given certain initial conditions. If cases arise in the future that show a shortcoming in the law, additional testing can be done to determine why it falls short and amend it. These edge cases point out the limits of our understanding. Sometimes, the tests to determine why there is a problem with a law bring new scientific breakthroughs and discoveries.

Laws don’t describe why they work, they merely describe the observation. To use Newton’s law of Gravitation again, we can determine how strong of a force 2 bodies feel in relation to each other due to gravity. We can’t, however, determine what gravity is, how gravity works, why gravity has a mathematical relationship, or what causes gravity in the first place. We can use the law to determine when Mars will be in what position so we can land robots on it, but we still have no idea why it works.

Theories

Theory – a coherent group of tested general propositions, commonly regarded as correct, that can be used as principles of explanation and prediction for a class of phenomena:

Dictionary Definition of Theory

In contrast with a law, a theory is both the observation and a well tested explanation for why it is that way. A theory can also provide equations to show how the observed phenomenon relate to each other. Oftentimes, the theory is put to test by others in the scientific field to rigorously test it and ensure that they can find no problems with it. If problems are found, the theory might be discarded or modified to account for those cases. Once significant testing has occurred, and no major issues are found, it may become accepted by the scientific community.

Some theories have been around for decades, if not centuries, and are well accepted by the scientific community. Others are new and compete to provide the best explanation of a phenomenon. If a new theory provides a better explanation for a phenomenon than an older one, the new one supersedes the old one. It is not a bad thing when this happens. To see a list of superseded theories, check out this wikipedia page.

Conclusion

Knowing how to approach the world with a scientific mindset is a good skill to have. When you can assess how likely it is that someone’s conclusion is correct based on their methodology, especially if you can examine their work, you can draw more conclusions about the world that are true. This allows you to better interact with the world in ways that make sense and work.

It’s important that science requires verifiable claims that can be tested. All majorly accepted scientific theories have undergone rigorous testing to ensure they are good explanations for what they claim to describe. When making a claim about the correctness or incorrectness of a claim, they do not argue from an acclaimed place of authority. Instead, they argue by showing the facts and methodology to verify or refute a claim.

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Evolution: It’s not a debate

Evolution: How Science Works

For some reason, many religions (Christianity in particular) seem to have a problem with Evolution. When I talk to my parents about religion, they always try to shoot me down by ridiculing evolution and using other terrible arguments. Unfortunately, they only show their own ignorance in their attempts to do so.

Most of their arguments fail because you need to understand how evolution works in order to adequately talk about it. In order to understand how evolution works, you need to understand how science works. Because of that, I’m going to start with a basic overview of how to do science followed by a few explanations of how evolution works. Then, and only then, will I address the problems in the arguments.

Definitions

I’m including a definitions section here so there will be less confusion when these words are encountered later.

Evolution: change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction

Heritable: (of a characteristic) transmissible from parent to offspring.

Heritability: Capable of being transmitted from parent to offspring. The quality or state of being heritable.

Hypothesis: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

Law: Scientific laws or laws of science are statements, based on repeated experiments or observations, that describe or predict a range of natural phenomena. 

Theory: A scientific theory is an explanation of an aspect of the natural world that can be repeatedly tested and verified in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results. Where possible, theories are tested under controlled conditions in an experiment

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