Where I live, the theory of evolution is regarded as being as truthful as the idea that the Earth travels around the sun. For this reason, I was surprised to find that a startling number of people still do not have an adequate understanding of the theory of evolution, and consequently attack it whenever they get the chance. To battle this ignorance, I have put together a simple article explaining the basics of evolution. I am not saying you need to accept it or believe it, but it is always good to learn something new!

The Basics of Evolution: How it Works

In an attempt to explain this in a simple, interesting and accurate way, I have decided to use bunnies as an example. Yay bunnies!

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Let us consider this group of rabbits, mostly all black, but with some natural variation in colour. As with most animals, slight differences in appearance occur within the species due to the random mixing of genes and small mutations within the species.

Now let’s consider what would happen if suddenly the weather got colder and it started snowing. Any black rabbits would be spotted by predators in an instant, and would quickly die. The slightly lighter rabbits would have a greater chance of survival, and may live to an old enough age to start reproducing. 

These rabbits who survive long enough would reproduce. The baby rabbits would have a mix of genes from both mother and father, and since it is likely that both parents are lighter in colour, there is a large chance that the baby would also be a light colour.

Now consider the green pairing. The baby rabbit is a very light grey, even though both of its parents are a darker grey. This is due to an error in the copying of genes during reproduction and is called a mutation. It is fairly common. It is the equivalent of you having say green eyes when both of your parents have blue eyes.

So now we have a population of slightly lighter rabbits than we had before.

As seen previously, before the darker rabbits are able to reproduce, they are killed by predators. This means they are unable to pass their dark-coloured genes on to future generations of rabbits, leaving only the lighter coloured rabbits to reproduce.

Again, the rabbits that survived to adulthood reproduce and pass on their genes to their children, resulting in the birth of more light-coloured rabbits.

If this process is left to continue, with the darker rabbits dying out, and the lighter rabbits passing on their genes to future generations, the population will eventually be entirely white! Our black rabbits have evolved into white rabbits. Not by accident, and not by chance, but by natural selection. The rabbits did not randomly or accidentally evolve, they did so through complex, lengthy and defined process, changing little by little through each generation. 

This is in principle how evolution works. Obviously it is more complex than this simplified explanation, but this gives you a basic idea of what evolution is. Now that you have some understanding, let’s move on to some common misconceptions.

Common Questions and Misconceptions

1. Humans evolved from monkeys

This has been corrected by people for so long it is a wonder that people still believe it. I think it is mainly due to this famous illustration which is most commonly associated with evolution:

The idea expressed in this photo however not that we evolved from monkeys, but that we shared a common ancestor with them. Imagine again our original group of black bunnies. Now imagine that this group split into two smaller groups, with one group moving into grasslands, and the other staying put in the snow. The group of rabbits in the snow would evolve into white rabbits, whereas the rabbits who moved into an area with dirt and dry grass would likely evolve into brown rabbits. There would now be two separate species of rabbits, brown and white, each with a common ancestor.

Like the rabbits, it is believed that both humans and apes shared a common ancestor, because our genes are so similar. Our ape-like ancestors evolved into two separate species. One group evolved into monkeys, while the other group through natural selection progressed enormously, evolving into the humans that we know now. 

2. It’s called the ‘theory’ of evolution. Doesn’t that mean scientists aren’t sure if it’s true or not?

This point is understandable one to make. In our everyday language the word theory is usually used when people just make up weird ideas with no evidence backing them up. For example a person might have a theory that there is a monster in their cupboard, when there is really no evidence to back up their statement. 

However, scientists use the word theory in an entirely different way. A scientific idea can only be regarded as a theory when all evidence that can be found supports the idea, and no evidence disproves it. It seems like a strange word choice, but the reason why scientists are reluctant to call it say, “the fact of evolution,” is because in science everything is changing and being improved, and nothing can be ‘proved’ with complete certainty. New evidence may be found that changes the understanding of the original theory, so that it has to be modified. You could say that the word ‘theory’ is used ‘just in case’ any evidence is found that disproves it.

That being said, because of the enormous amount of evidence in favour of the ‘theory’ of evolution, it is now widely regarded as scientific fact, and although new evidence is being found all the time, this evidence rather than disproving it, enhances our understanding of evolution.

3. What evidence?

There are many different forms of evidence which support the theory of evolution, studies of DNA, similarities between the body parts of different animals, experiments with bacteria and many more. However the theory that provides the majority of the enormous amount of evidence comes from studies of the fossil record, which is what I will discuss.

Imagine you cut a section vertically out a piece of rock and found this.

The lower layers of rock were deposited first, with the higher layers being deposited on top of that first layer. We can see that the lowest layer is the oldest layer of rock, and the top layer the youngest. We now have a sort of timeline of rock, where we can study the different fossils to see how life has progressed. We can clearly see that the fossils (of rabbits) deposited in each layer of rock gradually change or evolve from black to white as you move up the rock layers. We can now infer that over time, the rabbits have changed from black to white.

This is basically (although very simplistically) what scientists study in the fossil record. When organisms die the occasionally become trapped in rock and fossilized, preserving an image of this organism for as long as the rock in which it is trapped remains undisturbed. Scientists collect these fossils from different rock layers deposited over billions of years and study the changes in these fossils through the different rock layers. Through studying the immense number of fossils found, scientists have noticed a gradual change in the size, shape or features in each individual species studied. They have noticed the organisms evolving!

Wrapping Up

I hope this article has given you a greater understanding of evolution, and you have gained some valuable knowledge.

I understand that for many evolution means a direct attack on their religion, which is why many have ridiculed and opposed it, and in the process created a warped and incorrect view of evolution which I have sought to correct. My aim definitely is not to attack religion, simply to provide accurate information so that when people come to make a decision, they have information that is correct. For surely the best way to make a decision is to gather all the evidence first, then decide, rather than deciding first and then rejecting anything else that opposes it.

If you have any further questions, or you feel I have made any mistakes feel free to comment. Thankyou for reading!

For further reading:

Religion and science: compatible?

Religion and science: more

Wikipedia knows all

How Stuff Works – evolution – For more detailed information The Selfish Gene by Richard Dawkins is the best explanation of evolution I have found