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[Seussninja]

As someone who's taken a lot of molecular biology and organic chemistry at a rigorous institution of nerd-dom, I feel like I should dispel some "facts" about evolution that seem to have been ingrained in some of us.

I sincerely don't mean to call anyone out because many people certainly believe this, but it has been implied in this thread that the theory of evolution holds that humans evolved from apes. This is not true. All chemical systems that replicate using DNA (read: all life) are constantly evolving because of transcription/translation errors. Humans and apes are relatively new creatures in the world, and neither evolved from each other. However, they did originate from a common ancestor (CA). This is what evolutionary theory implies. It may seem like I'm splitting hairs here, but there really is a huge difference. To say that we evolved from apes implies that apes were running around on earth, and then we *poof* evolved from them as they continued to exist unchanged until today. Since everything is always evolving, apes as we know them didn't actually exist in the time of the CA. In fact, it was the CA running around on earth when some of its population evolved into the direction of humans while others evolved differently, in the direction of modern apes. (There was more than one fork in this path, to be sure, but this is just to illustrate.)

Next, the big bang theory came up. I hate when that happens in a discussion about evolution. The two have nothing to do with each other. The big bang theory attempts to explain the origin of the universe. Evolution does not. Rather, evolution is simply the net effect of a mix of random beneficial and harmful transcription/translation errors introduced to a population over an extremely long period of time. Evolution is not an attempt to explain the origin of the universe or life. It explains how new species evolve from existing ones. This is why Darwin titled his work "On the Origin of Species" and not "On the Origin of Life."

It was also mentioned that it's hard to imagine evolution without some sort of spark to start it. You may have no idea just how right you are, but first, a bit about oil and water:

Why don't oil and water mix? Bueller? Bueller? Water molecules are polar and have partial charges at different locations along the V-shape. The large electronegativity of oxygen pulls the shared electrons toward it, away from the hydrogens, creating a partial negative charge on the oxygen and partial positive charges on the hydrogens. In a cup of water, all of the water molecules are slightly attracted to each other because of the partial charges: the slightly negative O of one molecule will associate with the slightly positive H of a neighboring molecule, and so on. Oils, however, are altogether different because they don't have the same polar qualities as water. Long chains of saturated carbohydrates have practically no polarity because there's almost no difference in electronegativity between carbon and hydrogen. The chains are basically neutral in charge all over. For this reason it won't associate with a water molecule the way two water molecules will. Polar molecules crowd out nonpolar ones, causing the effect of water and oil not mixing. In addition, nonpolar molecules have a thing called the van der Waals force that helps them associate with one another, intensifying the separation between polar and nonpolar molecules.

And now we transition from oil and water to cell walls. There are some larger naturally-occuring molecules in our grand world that are polar at one end and nonpolar at the other. One class of these molecules in particular is known as the glycerophospholipid (I promise to not get too technical). The glycerophospholipid has two long carbohydrate "tails" that are nonpolar and a phosphodiester "head" that is polar. These molecules contain a ton of atoms, so a simple representation of them is often used. I drew one in Paint for you:



Now, remember oil and water. Polar associates with polar and nonpolar associates with nonpolar. Therefore, glycerophospholipids aggregate in the following way:



I know these aren't works of art, but let's press onward. The reason they aggregate this way is simple: each head is polar, so it wants to touch other polar heads, as well as the polar water molecules. The nonpolar tails are excluded from the polar heads and water. The tails associate with each other through van der Waals forces.

What happens when this structure, often called the phospholipid bilayer, forms a sphere? There would be an aqueous (water, polar) environment in the center, closed off by a nonpolar region (the tails), which separates the center from the rest of the environment. These structures occur in nature because of the propensity of oppositely charged species to associate and exclude uncharged species.

Could evolution have been a truly a random event? The odds of biological macromolecules and nucleic acids staying in close proximity to each other in the vast ocean of earth is next to zero, even if given trillions of years. Sometimes I get the feeling that some anti-evolution people believe this is what evolution is. However, what would happen if some key elements were trapped in the center region of the phospholipid bilayer? Evolution would happen a hell of a lot quicker for two reasons: 1) The concentration of key ingredients is MUCH greater. In such a small volume, the contents are constantly colliding and reacting with each other. 2) The phospholipid bilayer provides excellent protection from the outside environment. Not many substances could traverse the bilayer: a potentially threatening polar molecule would have to cross the nonpolar tail region. No thoroughfare, buddy. And a nonpolar substance? Good luck finding that in the ocean surrounded by polar WATER. As you can see, the phospholipid bilayer is the perfect "womb" in which to foster the development of sophisticated biological molecules from a few basic ingredients.

As you may have guessed, glycerophospholipids are the major components of real biological cell membranes. There's plenty of actual evidence for it, but you can see just by this that it's pretty logical that membraneous bilayers preceded living cells and are the precursors of modern cell walls and membranes.

So, the idea that evolution required some kind of "jump start" to get going is correct when you consider the fact that bilayer enclosures were required to get the ingredients concentrated enough. Whether or not you want to believe that God created the atoms and wavefunctions that allowed for differences in electronegativities and eventually the creation of phospholipid bilayers is your choice, but, as I said before, evolution makes no attempt to answer that question.

But wait! We've made a cell-like thing with some biological molecules and maybe organelles inside, but it's not actually made into life, or really evolution, yet. We're missing the ability to self-replicate. That's the one big step where there's still some real contention within academia. Today we need DNA and an elaborate manner of transcription and translation to replicate. The problem is how even an "evolution friendly" environment like the interior of the bilayer could foster the creation of such huge, complex molecules. Many wondered if it was possible. That is, until...

...the Miller-Urey experiment! Yay! Back in the day a grad student with cajones showed that in an environment similar to that of the harsh environment of early Earth, such molecules could absolutely have evolved. Basically he took some methane, ammonia, hydrogen, and water (which were all supposed to be very abundant in early Earth), put them in a flask at low heat, and shocked the flask with electricity every now and then (to simulate Earth's lightning). This was left to sit for a week or two. When he examined the contents, he found some amazing shit. Not only were there organic compounds, but there were entire nucleotides and amino acids! These are the building blocks of DNA/RNA and proteins, respectively. This was only 1-2 weeks; the possibility of a self-replicating cell doesn't seem so unlikely anymore when given millions of years to develop. So, as it was suggested, evolution may very well have required a "spark" to begin.

There has since been much controversy and criticism of this experiment. The most obvious point of contention is the assumption of what early Earth was like. So many other similar experiments were subsequently conducted using different possible starting materials. Most of them also had exciting results including amino acids; the only substance that seems to prevent this is oxygen. That's okay though, since it's a practically proven point that Earth began without oxygen in its atmosphere and that it was a heavily reducing (in redox terminology) environment.

I could go on, but I really should get to bed. I guess all I'm trying to get at is that evolution is not simply "humans evolved from apes" or something that some dude named Darwin came up with one day and the rest of the scientific community just decided to go along with it obstinately for the rest of eternity. Nor is evolution easily understood, and that's the biggest problem of all. Too many people in positions of power are concluding strange things about evolution and enacting public policy with their inaccurate assumptions coloring their decisions. It is painfully obvious that most people who have an opinion on the subject of evolution do not truly understand it, even at the most fundamental level.

I didn't get into how micro-organisms evolved into larger forms like birds and fish, but suffice it to say that individual cells aggregated often and localized certain functions to certain cells, the earliest form of symbiosis. Specialized aggregates of particular cells were the precursors of tissues and organs in modern animals. Diversification and evolution of species into new species is caused by built-in sloppiness and random mutations caused by the sometimes-faulty transcription/translation process. Anyway, I'm not here to teach anyone science, so I'll take my leave of this thread. Just know that even though I'm going because I'm tired, there's a ton more to it.

Here are some good links for further thinking:

Miller-Urey Experiment

Evolution Blog

Five Major Misconceptions About Evolution

If you wanna talk some more about it, I'm always up for an intellectual exchange. Hit me up on the PM.

Jesus Christ, I contributed something to a thread about evolution. I am soooo Internet right now. As soon as I cover abortion and the war in Iraq, I will have earned my e-wings.

Bra-vo

[Mommy]

3 things about that massive post that I didnt dare read all of:

1) Many theories do imply that humans evolved from apes. I have always heard two different stories. The one you are saying and the one that says that we came from apes. I have seen several diagrams showing the evolution from ape to human. Honestly, though, I couldnt give a fuck. Strong evolution makes just about as much sense to me as the theory of Creation.

2) Never did I correlate The Big Bang Theory with evolution. I was quite aware when I made that post that the two are different theories to explain different things. On the other hand, many of those who believe in hardcore evolution, hold the big bang theory to be true. I think the big bang theory is a crock of shit. My post was a bunch of random thoughts, most of which were not tied together. I know about Charles Darwin and his writings. I think that strict evolution and the Big Bang Theory hold little weight when truly explaining the "origin of species" or the origin of the universe.

3) Something cant come out of nothing. If you have nothing, how can something start? Big Bang Theorists attempt to bypass the theory of creation by creating a story that makes just about as much sense. Creationism says that there has always been a god. That makes no sense because how can something always be? On the other hand, Big Bang Theorists try to say that something started out of nothing (because they fail to explain where those atoms that started the event came from), a spontaneous explosion of events began. Im sorry, but that sounds stupid too. If someone wanted to say that god put the atoms there that started the big bang, why couldnt they just say that he created the universe? If we are going to go as far as saying that a god exists and started this chain of events, it could be just as plausible that Creationism is true. Im not saying I believe in either theory: creationism or evolution. My point is that evolutionists and big bang theorists say that their theories make much more sense in explaining how the universe and life began as opposed to creationism and I just dont see that. Here, it is necessary to lump the big bang theory and evolution together because those two theories are answers to the two questions that creationism answers. One theory for the universe and life as opposed to two theories for the univesrse and life. That would be my reasoning for dropping the big bang theory in the same comment as my comment on evolution.

This post has been edited by Jessica: Apr 7 2006, 07:53 AM

[Seussninja]

My main beef with creationism is that there isn't any fucking evidence or even an attempt to gather evidence. LoL God created da erf and dats all we need to know! Oh really? Can you explain any further, is there any science behind this? Or are you not going to even bother and just broken record at me.

I understand that the theories behind evolution aren't all concrete but at least they try to investigate further into it while creationists can stand behind their little castle and hurl insults at the hard working evolutionists.

It just seems like a cop out. "God is the answer." Oh, so if i'm trying to calculate pi to 493 digits i can just say "God" and get it right?

Seriously, fuck religion.

[Seeker]

"The Montreal Gazette today reported that a professor at Montreal's McGill University was refused a $40,000 grant, allegedly because 'he'd failed to provide the panel with ample evidence that Charles Darwin's theory of evolution is correct.' Ironically, the grant was for a study into the detrimental effects of intelligent design on Canadian academics and leaders." From the article: "Jennifer Robinson, McGill's associate vice-principal for communications, said the university has asked the SSHRC to review its decision to reject Alters's request for money to study how the rising popularity in the United States of 'intelligent design' - a controversial creationist theory of life - is eroding acceptance of evolutionary science in Canada."

Montreal Gazette Story:

http://www.canada.com/montrealgazette/news...eaa40f2&k=11346

[Mommy]

My main beef with creationism is that there isn't any fucking evidence or even an attempt to gather evidence. LoL God created da erf and dats all we need to know! Oh really? Can you explain any further, is there any science behind this? Or are you not going to even bother and just broken record at me.

I understand that the theories behind evolution aren't all concrete but at least they try to investigate further into it while creationists can stand behind their little castle and hurl insults at the hard working evolutionists.

It just seems like a cop out. "God is the answer." Oh, so if i'm trying to calculate pi to 493 digits i can just say "God" and get it right?

Seriously, fuck religion.

creationists cant explain the creation of the earth, but they can explain the fossil layers better than evolutionists can.

but yes, i agree with you on the point that creationists dont have proof, but on that same token, i dont think evolutionists have done a very good job, but at least they are trying which is more than can be said about the creationists.

[Spectatrix]

PHOSPHOLIPIDS!!! GLEE!

Why I get so excited about those damn things some 7 years after I had my college bio, I don't know... but phospholipids were all sorts of exciting and cool (and anthropomorphic) among my circle of friends.

Oh my god, I am SUCH a geek.

This post has been edited by Spectatrix: Apr 7 2006, 02:06 PM

[Divergent Realit...]

creationists cant explain the creation of the earth, but they can explain the fossil layers better than evolutionists can.

how?

[Seeker]

how?

<creationist>the dinosaurs went brokeback and god destroyed them for being gay, if america doesn't change he's gonna do the same to us</creationist>

[Mommy]

how?

mass flood

[Seeker]

mass flood

what does a flood have to do with creationism? how does a flood prove creationism? you don't think that climate changes can happen without the intervention of god? huh huh huh?

[Mommy]

what does a flood have to do with creationism? how does a flood prove creationism? you don't think that climate changes can happen without the intervention of god? huh huh huh?

i didnt say it proved creationism. I said they had a good explanation for the fossil layers in the earth. Other religions and such have a mass flood in their history though also so that doesnt even prove creationism really.

[Seeker]

i didnt say it proved creationism. I said they had a good explanation for the fossil layers in the earth. Other religions and such have a mass flood in their history though also so that doesnt even prove creationism really.

its scientific proof that a flood occured sometime in the past, all scientists agree, but again, what does a flood have to do with creationism?

if a flood explains fossil layers that's just pure science, i don't see your connection between a flood and creationsim

[Mommy]

its scientific proof that a flood occured sometime in the past, all scientists agree, but again, what does a flood have to do with creationism?

if a flood explains fossil layers that's just pure science, i don't see your connection between a flood and creationsim

the Bible has a lot of historical facts in it?

I can see why you arent getting what im saying. Im not explaining myself very well, but to be honest, Im too tired to do a lot of typing.

[Seeker]

you will type or you will be banned!1!!!

[Mommy]

you will type or you will be banned!1!!!

forum nazi