An Attempt At Explaining Evolution

There are a lot of misconceptions out there about evolution. Pedantic nutcases like myself give a long, low groan of horrible fiery pain when we hear questions like "If man evolved from apes, why are the apes still here?" In fact it was that question, encountered on a forum, that lead me to write the following. I have modified it and placed it among my editorial-type-thinggys for the amusement of whoever happens to stumble across this page.

EVOLUTION

Evolution is the change over time of an organism. Now, this 'change over time' is not like watching a human grow up. It is not a change that occurs within a single individual's life, it is a change that occurs in generations. (You cannot watch a monkey transform into something else, you would have to wait for it to have children, and observe how they are different to their parents, and then watch their children to see how THEY are different, and then THEIR children, and so on).

This is "Descent With Modification."

Evolution is not the Origin Of Life; it is, however, the Origin Of Diversity, or as Darwin put it, "The Origin Of Species". One kind of organism can split into different populations of that organism. Each population can evolve to different things, and diverge again and again (like the branches of a tree). This pattern produces a huge range of diverse life forms.

The fossil record is our eyewitness (rockwitness?) evidence of evolution.

When you look at the fossil record, you can see chains of organisms in which each link is slightly different from the one before it, and you can trace a path through these links from an animal like a fish through to a completely different animal, like a bird.

This is evolution, and basically, this concept is ALL it is. This "Evolution" is merely a description of what we see, it says nothing about how animals evolved, it is simply an observation stating that animals evolved.

In that sense, evolution is a fact, rather than a theory. But the word really refers to both fact and theory.**

Evolution is not absolute and deterministic: the results of evolution are generally not inevitable. Just because ONE group of apes evolved into humans, does not mean that ALL apes of that species are destined to evolve into humans. There is no absolute destiny for an organism's descendants.

And a species does not need to go extinct in order for it to have descendant species. That's the reason that the question "If man evolved from apes, why are the apes still here" makes evolutionists howl with pain: it assumes that the apes in question need to go extinct just because some segment of their population had humans for great-great-great-etc...-grandchildren.

(Aside from that logical flaw, two more errors with such an argument need to be pointed out:

1. "Apes" are not a single species (we are in fact one of the species of apes) - they're a group of closely related primates with particular features in common - orangutans, chimpanzees and bonobos, gorillas, humans.

2. The particular apes that we evolved from actually are extinct, anyway.)

Moving along.

Evolution is not a movement towards inherently "superior" forms of life.

People may sometimes say that we are the "pinnacle of evolution", or that advanced animals are superior to primitive animals. This is not true (as anything other than a subjective/aesthetic judgement). When a biologist uses the word "advanced", it basically means "new, or more recent". The word "primitive" means "older, or more like the ancestral condition". For some reason, there is an association between "advanced" and "better", or "primitive" and "worse" - this association does not apply in scientific language.

Evolution is *not* "movement from a simple lifeform to a more complex one". Although a simple organism can evolve into a more complex organism, it is equally possible for a complex organism to evolve into a simple one (for an example, just look at pretty much any kind of parasite), or for an organism tio evolve into something that is equally as simple/complex as itself.

And if a complex organism does evolve into a simpler one, this is not "devolution". There is no such thing as "devolution" or "de-evolution", and you will never ever hear a biologist use that term with their colleagues. It is not possible for evolution to happen "in reverse", because evolution from complex to simple, or re-aquiring of primitive characteristics, is still just plain old "evolution."

NATURAL SELECTION, RANDOMNESS, AND "INFORMATION INCREASE"

"Evolution" is a concept that does not depend on the origin of life. It is an observation of the change in populations of organisms over time. Evolutionary theory generally discusses how that change happens.

And that's where Natural Selection comes into it.

Natural Selection requires the following premises:

1. That a child resembles it's parents. (We know now this is because of genes being passed on from parent to child)
2. That a child doesn't EXACTLY resemble it's parents. (Because of recessive genes, and because of mutation in the genetic code)

Natural selection states that if an organism is better able to survive and reproduce, then it will survive and reproduce. If it is unable to survive and reproduce, then it will not survive and reproduce. Thus, good mutations survive and are passed on in the population, and bad mutations are weeded out. It's kind of like saying, "Good mutations are good, and bad mutations are bad". It is almost a truism.

Natural selection requires some random mutation in order to work, but it is not random.

There is a common creationist objection that random mutations should lead to an overall decrease in the amount of useful "information" in the genetic code - random mutations should accumulate over time, and instead of new organisms appearing, everything should eventually fall apart. More complex organisms wouldn't be able to appear; too many bad mutations would build up.****

Of course, because natural selection is not random, this objection cannot apply. The reason is that good mutations are preferred (by definition!). Bad mutations are weeded out, also by definition. If it was randomn, it wouldn't be called "natural selection".

Now this is the accepted theory on how evolution - an already established observation - occurs. A final point to make here: If you want to challenge Natural Selection, you must understand that you are NOT challenging Evolution. Evolution is already established by the evidence. Natural Selection is just the mechanism.

A NOTE ON RANDOMNESS

Natural Selection means that the effects of mutations on a species are not random, because anything good is favoured, while anything bad is chucked out.

But "anything good" is a wide range of possible things.

So even though natural selection is not a random process in one sense, evolution itself is still random in another sense, because there are a lot of different acceptable paths that a species can take.

FINAL THOUGHTS

Evolution is an extremely well supported theory, fact, and observation. A famous scientist (i forget who) once said that "Nothing in biology makes sense without evolution", and they were absolutely right. It is one of those "unifying theories" (like relativity, or continental drift) which explains a huge range of seperate observations in a particular subject area. For this reason, i and many others beleive it is important that the public has some understanding of how it works and what it is. Creationist groups in the US have no idea (literally, they have no clue about the nature of evolution or it's significance) what damage they could be doing by lobbying to get evolution out of the classroom.

Anyways, hopefully this essay was useful to somebody.

David Elliott

**note: when i say "theory", i mean "theory" in the scientific sense, not the creationist sense! Creationists waste a LOT of energy critisizing evolution by calling it "just" a theory, because they do not understand what the word "theory" actually means. I'm sorry, but it's true. A theory is a "system of ideas that explains and interprets a set of facts/observations", not "an unproven concept". back up

****This objection usually begins by describing the laws of thermodynamics, which state that the amount of entropy (often translated as "disorder") in a system always increases. If disorder always increases, then, they say, the "information content" in the genetic code would always decrease (overall).

This is all very misleading, however, for a few reasons.

Firstly, the laws of thermodynamics relate to the available free energy in a closed system; and the Earth's "system" is not closed - we get unimaginable amounts of energy coming in from the sun all the time.

Secondly, the "available free energy" has nothing to do with the "information content of the genetic code".