If there are any creationists or evolution sceptics following me, this post may cause a bit of trouble.
My first point is: There is a huge wealth of evidence that backs up the existence of Evolution. Many people point out that ‘Oh it’s just a theory’ or ‘But they haven’t found the missing link!’.
All I want to say to that is: Gravity is just a theory, I don’t hear anyone contradicting it. And so what if there is a missing link? If I saw a string of numbers that went: 1, 2, 3, 4, 5, 6, *gap*, 8, 9, 10. I’m not going to say: ‘Oh no, there is a missing link between 6 and 8, therefore this doesn’t exist!’ I’ll probably just try to look for, or figure out what’s missing.
For more examples of creationist anxiety I refer you to the following blogs:
Now on to the main post topic:
Evolution consists of two essential parts:
1) The creation of a new trait through random mutation.
Example: Imagine a world where all humans had one arm. One day a baby was made that mutated and developed two arms.
2) The new trait must be genetic, and therefore heritable.
Example: the baby with two arms grows up, has sex with someone and then has children who also have two arms. Hey presto, there are more two armed babies! This allows the trait to spread so eventually all of the species will have two arms.
I have to note here that this is a very extreme example and would never happen. Our arms obviously did evolve, but not in one great leap, they both evolved very slowly over a period of billions of years.
What does this mean for evolution? Well the problem with random mutations is that it can work both ways. You can have a mutation that does something good, and helps us live better lives. Or you can have a mutation that does something bad. We don’t get so much of the good mutations in our everyday life, at least not any truly significant ones, but we get a lot of the bad. Think of someone with any disability or condition that they inherited from their family. That’s an example of evolution when it goes wrong.
If we went back several thousands or even millions of years we would see something a bit different. Evolution would still go wrong, causing disability. The difference is that any animal (even humans) would quickly be killed by the environment and it would never be passed on (this counts for serious diseases like Huntington’s, to relatively trivial problems like short sitedness and hayfever). They could be killed by a predator, not be able to hunt sufficiently and therefore starve, they could even be left by their parents to die as a youngling.
OK so now for a famous Darwinian quote:
Survival of the Fittest
This basic principle goes as follows: If evolution gives rise to a heritable disability, that disabled animal would quickly die. If the trait did the opposite and did something positive then that animal would have a better chance of surviving in this world and therefore be able to pass on that trait.
So here is an example of positive evolution:
Imagine a Gazelle that evolved to be slightly faster. Now put it next to a ‘normal’ Gazelle. OK we have two Gazelle’s one slightly faster due to a random mutation from Evolution. Let’s say that they are being chased by a hungry tiger that wants to eat one. Who is more likely to survive?
Yep the faster one is more likely. That means that the normal one has died, whilst the faster, more evolved, Gazelle can go on to have more babies.
This gives us our next great evolutionary phrase:
And this is what I have been aiming for. Our single biological purpose in this world is to ensure the continuation of our own species.
We have sex and pass on our traits to our children who then pass on those traits to their children. Every now and then one of us mutates. If it makes us disabled we would probably die before having children, that trait is not passed on. If it helps us in some way, we are more likely to survive, and therefore pass that trait onto our children, ensuring evolution.
That trait will eventually become perfectly embedded into our entire species, furthering us through evolution.
So evolution isn’t designed to make sure we survive, it’s designed to make sure we have babies, passing on these traits. The most successful species is the one with the most kids.
So the meaning of life: to have babies and evolve our species.
If we go against it: our species is beaten by a more superior one (that’s partly why lots of other species around us are dying out, they can’t adapt fast enough in comparison to us).
- Just because there are ‘missing links’ or it’s just a theory, doesn’t mean evolution isn’t real!
- Mutations change our bodies for better or worse.
- If it’s better, we will survive and pass these mutations on, allowing evolution.
- As evolution only work through having children and passing on traits, the Biological meaning of life is: to have babies.