Saturday, September 20, 2008

Evolution For Dummies

Now please don't make the mistake of assuming that I'm calling anyone a dummy. I have encountered some very intelligent people here. It was simply a catchy sounding title.

I will attempt to explain the idea of evolution and show why it's actually not such a far fetched idea. I will be using my own words and describing evolution as I understand it to be. I am, by no means, a professional on the subject.

In the 1830's Charles Darwin visited the Galapagos Islands on his journey around the world. The Islands lie about 500 miles off the coast of Ecuador. Darwin observed the local finches, that there were many different species on this island that did not exist anywhere else in the world. Because the nearest land is 500 miles away, these birds could not fly the distance and so were marooned on the island so to speak.

Darwin wondered why there could be so many different species of finches on this island that were not found anywhere else in the world. They were all similar enough that it was clear that they had a common ancestor. Yet they were clearly not the same. Some were large, some were small. Some had large beaks, some had small. They had a variety of different colors. Some nested in bushes, some on the ground, etc. Why?

Darwin concluded that conditions on the island were the only explanation. As different groups of birds moved to different parts of the island, they evolved to fit in with their surrounding environment. How is that possible? Darwin's theory of Natural Selection explains.

The Theory of Natural Selection holds that species evolve to fit their environment. This, of course, is a slow process, but in some extreme cases it can actually happen rather quickly. For example:

Say we have a given area wherein lives a certain type of bug. Some of the bugs are white and some are black. It is about a 50-50 mix. This area also has bug eating predators. The environment is mostly black trees and the bugs live in the trees. What is going to happen according to natural selection?

The black bugs are not going to be eaten early as often as the white bugs due to the nature of the environment. Why? Simply because the black bugs are harder to see by the predators. Soon the white bugs would disappear entirely and because only black bugs are left, they will only have black bugs as offspring. This species of bugs has evolved by natural selection to survive in it's environment. If the trees had been white, then the black population of bugs would have been eliminated.

Imagine this kind of a process happening again and again over a time period of millions of years! It is plausible that some extreme changes could occur. Now say that this species of bugs was forced to move to a different area. This area is white and their only defense now is to hide from their predators in holes. The holes are small so only the smallest of the black bugs are able to fit inside. The rest get eaten. The result is that all of the small bugs are now producing offspring that are smaller as well.

We have gone from a multi-colored, multi-sized species to a small, black species. While this is just an example, it demonstrates that the idea of a species evolving to survive in it's environment is not such a far fetched idea.

Back in the early days of Chemistry, when the periodic table was being formulated by grouping the characteristics of the known elements, scientists found that many "spots" in the table were empty. These empty spots would, in the future, contain newer discovered elements. In fact, these empty spots, based upon their position in the periodic table enabled scientists to predict what elements would fit and even to predict their properties long before they were ever discovered! Pretty cool, huh?

The same is true of evolution. Assume that a certain species has evolved over a million years. It's original ancestor looked a certain way and the species today looks a certain way. Obviously they are different. What would the species look like half way through the million year period? It should have characteristics of both the original ancestor and the species today. Using this type of reasoning, scientists have predicted what a mid-species would have looked like. Amazingly, fossils are later found which do indeed look very much like what the mid-species was predicted to have looked like.

In our bug example, we went from black and white, large and small bugs to just small, black bugs. What is the mid-species? Large and small black bugs. The fossil record is another very strong evidence for evolution. We find bones of animals that no longer exist, but obviously they once did exist.

There is fossil evidence linking birds to dinosaurs. A dinosaur species has been found that actually had feathers!

Personally, I find it amusing that so many people are opposed to science but then they will turn around and say that science proves their point. Anyone who claims that science proves the idea of intelligent design has no idea what science really is. People who claim that science proves the existence of god are purely ignorant. Science will never prove the existence of god, because god can not be observed and tested.

Science accepts Charles Darwin's Theory of Evolution. Anyone who claims anything else is lying or just plain ignorant. Now just because we call it a theory does not mean that we don't understand it. In fact, in every day language, "theory" means an idea. But in science, a theory is an accepted statement that has been verified by numerous studies and scientists. A "hypothesis" is an educated guess based upon what has been observed. A "theory" is a hypothesis that has been tested and found to be true. If a hypothesis is found to be untrue, then it is revised and tested again. This is repeated until a "theory" emerges.

Check out this video which explains evolutionary theory quite well.

As you saw in the video, Darwin concluded that if the earth has undergone tremendous geological changes, then animals too would have to change. If they didn't, they would perish.

If Christians truly believe that science is evil, then they need to throw away their computers, turn the power off in their homes, sell their cars, and outright reject anything else that science has provided.


Jessicasheley said...

“There is fossil evidence linking birds to dinosaurs. A dinosaur species has been found that actually had feathers!”

Please do share what fossil evidence you are referring to. I’m assuming you are not referring to one of the many dino-bird fossil hoaxes coming out of China, such as the Archaeoraptor hoax. If you are referring to Archaeopteryx, it is my understanding that the world authority on birds, Dr. Alan Feduccia, at the University of North Carolina at Chapel Hill (an evolutionist himself) has said this was a perching bird and not a feathered dinosaur.

From what I have read, scientists are now questioning the dino-bird link:

“We now question very strongly whether there were any feathered dinosaurs at all.”

“No good evidence exists that fossilized structures found in China and which some paleontologists claim are the earliest known rudimentary feathers were really feathers at all…”

“The theory that birds are the equivalent of living dinosaurs and that dinosaurs were feathered is so full of holes that the creationists have jumped all over it, using the evolutionary nonsense of ‘dinosaurian science’ as evidence against the theory of evolution," he said. "To paraphrase one such individual, ‘This isn’t science . . . This is comic relief.’"


“If plants and animals did not evolve from a common ancestor, how come they are so similar on the cellular level?”

A common Designer perhaps?

Long Ben Avery said...

You asked for proof!