Life's origin, outer space (maybe)

[Tikker]

semi interesting read

Life in Space


basically, it's just saying that important bits of stuff could have been delivered to earth (or any other planet) via meteors, and when the right combination was present, life arose

[Ouchyfish]

I had read somewhere (Discovery magazine maybe?) that at one point back in time the earth was way too volatile a place for life to exist. Shitloads of acid I think. The scientists were theorizing that the amino acids had to have come on a meteorite or chunks from a comet etc.

[Tossica]

It was god, you dummies.

[Spazz]

YOur goin ot hell dude. Everyone who comes here knows by now that god created life.


But i myself have wondered if meteors and the like have had anything to do with life being created.

[Donnel]

You're.

[Spazz]

Ya got me.

[Donnel]

I know.

[Eziekial]

I'm reading "a short history of nearly everything" and the more the author tries to make a point that science is the answer to everything, the more I believe we don't really have any idea how or why we are here. Cosmic dust anyone?

[Lyion]

I'm reading "a short history of nearly everything" and the more the author tries to make a point that science is the answer to everything, the more I believe we don't really have any idea how or why we are here. Cosmic dust anyone?

Dude, Random Mutation & Natural Selection is fact, don't you know. We have all the answers.

[Arlos]

Random Mutation & Natural Selection is fact, don't you know.

Why yes, yes it is, thank you for finally admitting it, Lyion.

We actually just discussed origins of life in my Paleontology class recently. Intersting stuff. More details:

The oldest rocks we have dates for on Earth are about 4 billion years old. The oldest rocks we've found from the Moon are 4.5 billion years old, and the single oldest rock crystal on the earth ever found (a chunk of mineral crystal inside a sandstone) is 4.4 billion years old. So, given that the Moon was created about 4.5by ago, and the formation rather radically changed the Earth (gee, what a shock, take a planet the size of the earth, slam a planet the size of Mars into it, and you get lingering effects) we don't know a whole lot about Earth 1.0 which existed before that impact, most of what we know is post-Moon formation.

Now, by looking at rocks going back to just after Earth 2.0 got going, we can actually learn a lot about the state of the primitive Earth. First, certain kinds of minerals and compounds will form only when there's no water around, and some require water to form. (this is how we just figured out there was once water on Mars from those rovers, looked at the types of rocks). The earliest rocks we have with evidence for any appreciable amount of water are about 3.8 billion years old. Now, along with the influence of water, the gas makeup of the atmosphere also effects what kind of rocks and minerals, etc. are formed. So, by looking at the types of rocks, we can get a good idea of what the atmosphere was like back then too. Apparently, by looking at the gases released in volcanic eruptions (H2O, CO2, CO, H2, N2, SO2, H2S, CH4, NH3, etc.) and their relative quantities, it's entirely feasable to go from no water to liquid oceans & that atmosphere in 700my mostly from volcanic eruption byproducts. Also, the types of minerals formed back then are consistent with an atmosphere composed largely of volcanic gasses. (Also, by looking at the % of noble gasses in the atmosphere, we can tell it's very different from that which was left over from the original cloud that formed the solar system)

Now, as an additional factor, we know that lightning has always been occuring. As of right now, lightning strikes the earth 300 times a second. So, there's a constant energy influx to the ground and the water as well, so keep that in mind.

So, about 40-50 years ago, someone did an experiment to test the possibility of spontaneous generation of life. What they did, is they basically took a bunch of water, then added to the closed system an atmosphere just like that of the primitive earth, then sealed it all off, with the added feature of a spark generator in one part of the system to simulate lightning. What they found is that in a remarkably short time, starting with nothing but water and atmosphere, you get a large amount of amino acids spontaneously forming. This is most interesting, because amino acids are the basis for every living thing. In a more recent experiment, where they've added the additional factor of adding some fine grained sediment to the water, they found that the specks of dirt acted as bonding points, and the amino acids were using them as anchors to combine into complex protein-like structures.

Now, none of those experiments lasted decades or centuries, or millions of years. The earliest fossils we have of primitive life (single celled organisms, so primitive they have no cell nucleus, just goop with some DNA strands floating in it) are from about 3.5 billion years ago. So, if we, in the lab, with conditions like primitive earth are getting amino acids combining into complex forms in a matter of weeks or at most months, it is not a very large leap to posit that given an entire planet and 300 million years, that things could go from amino acids & proteins to something that we'd call life. Heck, if you want to believe goddidit, certainly makes more sense to me that "God" or whatever you want to term it was the spark needed for that final step, than to believe that the earth is 6000 years old and that Dinosaurs lived with Adam and Eve in the Garden of Eden, which I've heard a ID proponent claim in a speech.

Now, it is certain that comets did indeed import significant amounts of water and organic compounds to the early earth, but even if we are to assume that they actually brought the original life, that merely puts off the question. If life isn't native to here, it must be native to somewhere, and we're right back to the same question on how it got started THERE.

In any case, we know mutation & natural selection happen, we can observe them occuring, especially in short-lived species like bacteria. (ex: How many influenza versions are there? How many diseases are now antibiotic resistant due to selection processes?) We simply don't have the life span to observe 50000 generations of something that lives for, say, 20 years, to be able to chart the incremental changes that, when put together, mark the evolution of one species into another.

-Arlos

[Minrott]

So, about 40-50 years ago, someone did an experiment to test the possibility of spontaneous generation of life. What they did, is they basically took a bunch of water, then added to the closed system an atmosphere just like that of the primitive earth, then sealed it all off, with the added feature of a spark generator in one part of the system to simulate lightning. What they found is that in a remarkably short time, starting with nothing but water and atmosphere, you get a large amount of amino acids spontaneously forming. This is most interesting, because amino acids are the basis for every living thing. In a more recent experiment, where they've added the additional factor of adding some fine grained sediment to the water, they found that the specks of dirt acted as bonding points, and the amino acids were using them as anchors to combine into complex protein-like structures.

That's actually the most interesting thing I think I've ever seen on this board.

[Lyion]

http://video.google.com/videoplay?docid ... ty+in+cell

[Tikker]

I'm reading "a short history of nearly everything" and the more the author tries to make a point that science is the answer to everything, the more I believe we don't really have any idea how or why we are here. Cosmic dust anyone?

Dude, Random Mutation & Natural Selection is fact, don't you know. We have all the answers.

Random Mutation & Natural Selection are pretty much fact

they're obviously not all encompassing, infallible, completely filled out laws/theories (yet)


Sure beats the fuck out of "God did it, despite the lack of proof, witness, repeatability, or anything else even remotely smacking of evidence"

[Arlos]

Watched it.

My opinion: Utter Crap. More holes than a cubic meter of swiss cheese. Makes more unsupported claims than you can shake a forest of sticks at, then uses those claims as some sort of "proof". Shoddy, shoddy work, would get laughed out of any peer-reviewed science journal.

The first part is a tolerably decent review of the AP high school biology I took back in like 86. It then proceeds to make a long list of completely unsupported allegations. "Life couldn't possibly be this complex without a supreme creator", "Life in perfect harmony" and similar such statements. Bullshit. You want an example of a so called "perfect" animal? Look at a Rabbit. Frequently in the wild, in order to get enough nutrition because its digestive system isn't as good as that of, say, a cow, Rabbits have to eat their own feces and re-digest the plant fiber a 2nd time to get more nutrients out of it. Oh yeah, some brilliantly intelligent design there, eh?

Also, the type of cell being discussed here is a Eukaryotic cell. The first forms of life, similar to the cyanobacteria we see in colonies today, were Prokaryotic cells. Prokaryotes have effectively no internal cell structure. They don't even have paired chomosomes. Even today, the vast majority of life is Prokaryotic in nature, including the bacteria found by the hydrothermal vents, etc. Prokaryotic cells first appeared 3.5 billion years ago. You know when Eukaryotic cells appeared? 1.8 billion years ago. In other words, in all of the time that life has existed on the planet, HALF of that time was spent before evolution ever produced the first known Eukaryotic cell. Indeed, one of the hypothesis about how Eukaryotes came to be is that several Prokaryotes ended up in a symbiotic relationship with each other. This helps explains, for example, why mitochondria has its own DNA; because originally it was an independent organism.

The film then shows maybe what, a dozen dissenting scientists, who believe in Creationism. You could probably find a dozen people who believe that the Earth is flat or that the Holocaust never happened, too. Doesn't make them right. Care to examine the percentage of molecular biologists who believe in Creationism vs Evolution? Betting it's running 95-5 in favor of Evolution, if not closer to 99-1.

Following that, it goes into a long diatribe about the Eye. Again, a review of high school biology. It also conveniently ignores the fact that the mammalian eye actually has a number of serious design flaws, while at the same time calling it "perfect". What flaws, you ask? Well, for one we have a blind spot caused by the channel the optic nerve passes through. Also, the way the blood vessels connect to the retina, it is possible for the retina to become detached and pull away. BTW, Squid eyes have neither defect, and they see very well indeed. There are actually several good treatises on how the eye evolved, at least one link has been posted here.

At the very least they were honest in one thing: that their whole point was to try and claim "Goddidit". Too bad for them, it was laughably bad. 6 year olds could poke holes in their "logic". Again, ID is just repackaged Creationism, it is in *NO* way Science. It is the antithesis of science. It is untestable, it is unprovable, and provides no useful methods of prediction. That's what a scientific theory DOES. It not only provides explanation for observational data, but it has predictive value. By its very definition, ID is incapable of providing any predictions whatsoever. Therefore, it is completely unscientific.

-Arlos

[Harrison]

You want an example of a so called "perfect" animal? Look at a Rabbit. Frequently in the wild, in order to get enough nutrition because its digestive system isn't as good as that of, say, a cow, Rabbits have to eat their own feces and re-digest the plant fiber a 2nd time to get more nutrients out of it. Oh yeah, some brilliantly intelligent design there, eh?

Worst attempt ever.

[Arlos]

*shrug* not my example, I grabbed it from somewhere. Still, if, as ID claims, all life is the result of a perfect intelligent designer, why design something so obviously imperfect?

-Arlos

[Metranon]

*shrug* not my example, I grabbed it from somewhere. Still, if, as ID claims, all life is the result of a perfect intelligent designer, why design something so obviously imperfect?

obviously ID will respond, "the rabbit does fit perfectly into the design of the system of life as a while, but humans by definition as imperfect beings don't have the capacity to see how"

unfortunately (or fortunately, if you prefer) there is no premise that can be made to support this

on a related note, check out this article:

http://physicsweb.org/articles/news/9/9/14/1

so basically it's possible to build carbon-based "computers", while not in the realm of reality yet

[Tikker]

the best part of ID:


whenever you back ID/creationists into a corner, and ask them to prove something (ID is a scientific based theory, remember?) their only response is faith

[Lueyen]

In a more recent experiment, where they've added the additional factor of adding some fine grained sediment to the water, they found that the specks of dirt acted as bonding points, and the amino acids were using them as anchors to combine into complex protein-like structures.

Fine grained sediment and specks of dirt... essentially dust... so life began in part from dust... where have I heard that one before?


[/quote]

[Lueyen]

The missplaced "[/quote]" in my post above brought to you by those annoying touch pads they put on laptops.

[brinstar]

someday, centuries from now, people will laugh at those who refuse to believe in evolution the way we laugh about those who refused to believe in heliocentrism

[xaoshaen]

someday, centuries from now, people will laugh at those who refuse to believe in evolution the way we laugh about those who refused to believe in heliocentrism

Are we simply ignoring the fact that heliocentrism was wrong?

[Eziekial]

I am, I love believing we are 3 rows away from the center of the universe.

[Langston]

Actually, Heliocentrism is wrong.

Langstoncentrism is what all the cool scientists are claiming to be true, now.

[Zanchief]

I believe Zeus created the world. It's pretty much scientific fact.