Evolution in a nutshell

It’s pretty simple.

Do you look exactly like your parents? I mean, literally identical? You may have your mum’s nose, and your dad’s ears, but you’re not a carbon copy. You are different.

What happened there, you see, is evolution. You were created by mixing two sets of genes, and the result was something pretty similar, but not exactly the same. You may have the colouring of your parents, or if they’re tall it’s quite likely you will be too. But you’re not literally identical.

It’s called mutation.

Now multiply that by a few thousand generations. Bingo. Evolution. And the earth has been here for 4.2 billion years, with life for the last 2 billion. There’s been plenty of time!

“Ah”, I hear you say, “I accept that evolution might make humans have darker skin or be taller, but it can’t change a mongoose into a squirrel”.

Let’s imagine a herd of grazing animals on the grassy plains of Africa. They’re a kind of antelope. Just as with humans, there is some small variation between individuals. Some are taller. Some are weaker. Some have better eyesight. It’s only a tiny difference, and most of the time it doesn’t count.

Then a lion attacks. The antelope with the best eyesight sees it first, and runs into some trees.

The taller one has longer legs, and can run faster, and he heads out onto the plain.

The weaker one gets eaten.

The antelope with the good eyesight hides in deep undergrowth, and meets another “good eyesight” antelope, and they have kids. This continues for many generations, with the eyesight getting better, and the animal getting smaller so it can hide in bushes. In time, you have a Dik Dik. Huge eyes, tiny body, timid.

The antelope with the long legs ran onto the plain, where there were taller trees. He met another tall antelope, and they had babies, who inherited some of the features of their parents, including being tall. The tall babies survived when a drought came, because they could reach leaves that were higher up. Over many generations, the trend was for the antelope to get bigger and bigger. Zip forward 200,000 years, and you have a giraffe.

In the meantime the lions are also going through an evolutionary arms race. Getting faster, stronger, smarter. One species pushes the other. Different environments produce different results.

It’s called Evolution, and it’s the truth.

Intelligent design.

Some people say “OK, we believe evolution happens” (because frankly, to deny it is like denying the sun exists). “But”, they say, “it’s happening because God directed it according to His intelligent design”.

And my answer to that is: the laryngeal nerve.

The laryngeal nerve is a nerve which goes from the brain to the larynx, and helps with swallowing (and in animals that can make sounds, it controls vocalisation).

It first developed in fish. It took the shortest route from the brain to the larynx. In a fish the heart is close to the brain, right up behind the gills. So the nerve travelled down from the brain, went behind the heart, and then to the larynx. Note it goes behind the heart. That was the shortest distance.

When fish evolved onto land (something the lungfish is still doing today, evolution fans) they needed to be able to move their head in new ways, so they could spot predators. So they developed more of a neck, and that meant some of the organs got pushed down into the torso. Including the heart.

The laryngeal nerve still went behind the heart, but had to take a longer route. It’s much easier to adapt something than to scrap it and start again, so that’s what evolution did: it just kept extending the nerve in each generation, tiny change by tiny change.

Every land animal, dinosaur, lizard, bird, mongoose, bear, whale, cat and human has evolved from those early fish. And in every one of us, the nerve that controls our swallowing and vocals starts at the brain, leads down the neck, wraps around our heart, and back up again to the larynx.

Even the giraffe. A 22 foot long nerve to pass a signal to the larynx, which is only 4 inches away from the brain.

Intelligent design? If that’s as good as God gets, He’s not intelligent at all. And that’s not a design. That’s the result of unplanned chaos.

The truth is, evolution is random and uncontrolled, and only has the appearance of being “designed” in the same way that the water in a puddle fits perfectly into the depression in the ground. Nobody designed the water, it just works that way because of the laws of physics and chemistry.

Similarly, nobody “designed” a Dik Dik, it’s just the best solution for the environment it’s in. Change the environment, and the animal changes too.

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