h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I'm new to this discussion so dont hesitate to shoot me down if this has been said before!

I come from a strange perspective, I was brought up a christian but now waver between being an agnostic and an atheist (more atheist at the moment but I could be wrong, we'll never know till we die! ). I am also a biologist.

Evolution does exist, you can see it in action, but evolution does not explain how life came into "being". This is where my sitting on the fence comes in. The Idea that life occured by divine intervention by a supreme being and the idea that the conditions of a young planet caused life are both long shots, with astronomical odds against (although at least the latter theory has some grounding in evidence based science).

As both theories are full of holes militant supporters of each ridicule the opposite view. The truth is no one knows and no one ever will and it is equally plausable that a combination of the theories exsits (as with the veiw of "modern creationists" i.e. not literal creationists). For all we know aliens may have kicked off life on this planet, or lifes building blocks may have come on asteroids (although both these possibilities raise the question how did they get there?).

So basically if you disagree with either theory, it dosn't make someone who believes in the other a nutter or ignorant, its just the idea that they are comfortable with.

Well I'm going to jump off the fence here and say my personal belief is that yes it was just a random event. But hey, I could be wrong.

Phewwww! Hope that made sense

"Evolution does exist, you can see it in action, but evolution does not explain how life came into "being"."

Evolution doesn't even attempt to though. It explains how life changes and adapts. What it does do though is infer that all current life came from an original progenitor. Take a look at an evolutionary tree all the way down to the archeabacteria. All the branches come from one point in there somewhere.

And that is where evolution reaches it's limits. Anything before starts to become speculation, though experimentation (Urey-Miller expt.) and observation (amino acids have been detected in space) seem to indicate that the building blocks of life all happen naturally. Add a reducing atmosphere and that stuff will start to react together until a self-replicator appears. Our oxygen-rich atmosphere of today is oxidating and tends to break stuff down, put simply. Life wouldn't have happened in such circumstances.

Ah, I'm digressing. Cool.

Ste

However, archaebacteria are all similar enough that creating a chain of them through fossils largely depends on what you want to happen.

We run into problems when we try to create a chain of fossils of mammals or reptiles.

Yes of course. It has been estimated that fewer than 0.1% of life gets fossilised, and most of that is near lakes, rivers or seas. The chnaces of finding convincing transitional forms is remote. There is an excellent entry on cladistics knocking around somewhere. Cladistics is slowly taking over from the 'descendency' advocates and works instead on degrees of similarity - it states that narratives describing descendency are opinionated and flawed by the spin of the narrator - intentionally or otherwise.

Sorry Josh, don't quite get you?

Why fossils? and what do you mean by a chain?

Ste

Ps - Although I don't agree with Creationism, I must say that whilst defending evolution theory, some take descendency a little too seriously.
Josh - the evidence for a chain of transition forms leading from, say, shrew to ape has not been discovered, and almost certainly never will be. The fossil record is incomplete - fossilised animals are rare. By stating that there are no transitional forms in the fossil record, you are making no point what-so-ever, and are merely stating the obvious. This lack of fossil record proves nothing about evolution one way or the other. You want proof of evolution (although I must say I prefer the straight 'adaption' - fewer misleadin associations)? Get bad flu and take penecillin for it. Repeat the process until the penecillin is no longer effective.

The antibiotic-resistant strains of bacteria running around really *do* make an excellent case for evolution, Frogbit. Also, a bit scary, really.

ali, I have the same problem as you. Evolution is all well and good to a point. We can even trace back evidence to the Big Bang. What then becomes the question is who/what created the Big Bang. And it certainly could have been a random event, but who's to say? Isn't that the whole thing in a nutshell, that none of us actually KNOWS anything for certain?



This has all sorts of existential connotations written all over it!

"Isn't that the whole thing in a nutshell, that none of us actually KNOWS anything for certain?"

This is, of course, always worth remembering. There is also no such thing as a right or wrong opinion.

But...as another researcher said (apologies for not being able to remember which one) - disproving theory A does not prove theory B.

I'd just like to say that no-one (to my knowledge) has commited genocide trying to prove evolutionary theory correct.

Although Mengele certainly tried something of the sort, so maybe that's best left undecided, yes?

Well, then, we've reached the crux, haven't we? That creation and evolution are, well, two sides of a coin. Is this just something ingrained in Western culture, that everything must be an either/or argument? I prefer shades of gray, myself.....

But debating the issue always mixes the colors.

Now, then, to raise a point:
If our geological/biological evidence for evolution is sketchy at best, than what does that do to the argument that it is more "scientific" than creationism?

To Josh and Ste, I thought we were having a sensible discussion on this topic in another thread. Don't get sidetracked into a slanging match please.

"If our geological/biological evidence for evolution is sketchy at best, than what does that do to the argument that it is more "scientific" than creationism?"

Science creates stories based on bones.

Creationism creates stories based on preferences.

Well, okay, but aren't the bones viewed through filters just as much as mythology is? Really, in looking at a fossilized femur, how do we know, OUT OF CONTEXT, what it is any more than we know what theology is to different people OUT OF CONTEXT? i.e., the inquisition seemed like a perfectly reasonable response in the 13th century. Now, not so much.

Though I have a deep love of palaeontology and environmental geology, I couldn't agree with you more. There are a couple of things I have to say before I get to the point.

I don't think we are descended from apes. We *are* apes.

Nothing is more evolved than anything else. Everything is perfectly adapted to its environment, and this state of affairs changes only when the environment does.

The point.

A turtle, I assume, knows enough to be a turtle. There are limits to a turtle's intellect.

An ape is, in my view, similarly equipped.

If the two prevailing views, that is, evolution theory (hey - is everything changing around here?) and Creationism (No - things don't change - the big daddy ghost ape made it that way) are the best we can do, then it wouldn't be unreasonable to posit that we're missing something.

Out of the two views, the observation that things change is more useful to me than the big daddy ghost ape thing.
We *know* things change. This can be observed.
We don't know about the big daddy ghost thing. We have to take the word of believers for it.

That's what I like about geology - it doesn't ask you to believe in anything you're not already standing on.

Frogbit.

Hi Madent , I won't and I wasn't . Thanks for the reminder though.

Oh and just a quick mention that the geological evidence maybe sketchy, but the biological evidence is anything but .

Ste

Well, okay, but do you see what I mean? We have only a few hundred years of scientific observation to rely on for that. The Enlightnment was called just that for a reason, after all. Then again, that's what Darwin countered with when he was criticized, wasn't it? That things didn't just sit around waiting to mutate until someone noticed them.

Of course, the smart thing to do would be to learn Arabic, go back in time and undo the destruction of the library in Alexandria. Then we might have another millenia of information.

Ignoring fossils, the examination of DNA of living creatures can provide immense evidence about the relatedness of various species, and is much less prone to the problems of interpretation ("Is this jawbone more like species X or species Y?")

Darwin developed his theories from the observation of living animals, and from the application of logic to the issue of differential reproductive success. Even if the past conditions had been such that animals had never been fossilised, someone would eventually have arrived at the same conclusions.

However, one thing fossils *can* show without question is that there were many things alive a very long time ago that are different to things alive today, some very different, and some interestingly similar, and radioactive dating can give a very good idea of when those creatures were living.

"Science creates stories based on bones.
Creationism creates stories based on preferences."

Science is not always objective and bones are open to intertretation. Where it is different is that everyone (potentially) has access to the same primary sources, so scientist B can look at the work of scientist A, study the sources and come to her own conclusions - then other people can examine the evidence and join in the fight. Hardly anyone gets killed.
Conversly.
A religious leader says: "I have divine knowledge, if you need an answer come to me, you can trust what I say." A rival says: "No, I have divine knowledge... blah blah blah... you and your followers are going to hell." Some followers say: "that chap seems sensible," and millions die of bigotry.
This is a very long-winded way of highlighting the concepts of reason and faith.

Geology is a lot like history. We may know facts, but how we put them together, how we interpret the data, as it were, determines what sort of outcome we get.

There's statistics, damned statistics, and lies, to quote someone famous (although at this point in the semester, I cannot remember who).

So neither creation or evolution is free of bias. Although at least science doesn't usually threaten eternal damnation for a disagreement!

How we put together a few of the facts from geology may be subjective, but there are also basic ways of puting things together that are objective.

If a bank of rock is composed of a series of layers of sedimentary origin, it's a pretty sure bet that the layers were originally (near) horizontal and planar, so that if the layers aren't horizontal and/or planar now, something has happened since their creation, and given a set of layers A,B,C,D,E, there's a chronological progression - almost always with the lowest level earliest (and in the cases where layers are locally inverted, it's highly likely that nearby there will be layers in the normal sequence, or other evidence of which way really was up at the time when they were formed.

Re: The beginning of life

Here's an interesting article from Science online (go to http://sciencenow.sciencemag.org/cgi/content/full/2002/415/3) regarding the most recent thinking on the origins of the first cells on Earth.

If the link doesn't work (I think you might have to subscribe to see it, but I'm not sure, this is from a work computer) I'll copy and paste the article (with suitable references to keep the copyright moderators happy).



Ste