The Talk.Origins Archive Post of the Month: April 2009

Subject:    | Mass Stupidity
Date:       | 10 Apr 2009
Message-ID: | Xns9BE95BD97FCE7jimwillemingmailcom@216.196.97.131

[M]adman wrote:
>>> Anyone actually believe mankind can establish what happened on earth
>>> 3 or more BILLION years ago?

Jim Willemin reponds:
>> Everything that happened? No. The evidence for most of what
>> happened then has been utterly destroyed. Some of what happened
>> then? Yep. If we gots the rocks, we can start to constrain what
>> happened and what didn't. Why, does it need to be all or nothing for
>> you to be happy?

[M]adman wrote:
> Well, every puzzle needs a certain amount of pieces in place in order
> for the picture to become clear. Are you confident that there are
> enough 3.8 billion year old rocks to assertain a clear picture;
> accurate picture? Doubtful. You said yourself "The evidence for most
> of what happened then has been utterly destroyed". And as you will
> see below, some feel "Dates prior to 1 billion years ago are
> speculative."

Jim Willemin replies:
I guess at this point I need to ask 'What the hell do you want?'. What, in your mind, is 'a clear and accurate picture'? Do you need to have satellite maps of the planet's surface with geochemical maps of both land and sea to have a 'clear picture'? We can have only glimpses of things that far back. Those glimpses provide accurate vignettes, and some have more global implications, but CNN coverage it ain't.

For example, last September a team published samarium-neodymium results from the Nuvvuagittuq greenstone belt of Quebec that suggests those greenstones are 4.28 billion years old. (O'Neil et.al., 2008, Neodymium-142 evidence for Hadean mafic crust, Science, v.321, p1828-1831; abstract available at http://www.sciencemag.org/cgi/content/abstract/321/5897/1828 ).

Now, all of those rocks have been metamorphosed, but some were originally volcanic, and some were chemical sediments that precipitated from sea water (you can tell by the isotopic composition of the iron in the minerals: Dauphas et al., 2007, Identification of chemical sedimentary protoliths using iron isotopes in the > 3750 Ma Nuvvuagittuq supracrustal belt, Canada, Earth and Planetary Science Letters, v. 254, p.358-376, abstract available at http://tinyurl.com/c4xzsr). Other rocks in the same location are probably metamorphosed conglomerates (Cates et al., 2007, Earth Pl. Sci. Lett. v.255, p. 9-21).

Now, what does this little bit of greenstone in northern Quebec tell us about the earth 4 billion years ago? It tells us there was a crust, that there was water on that crust, that there were volcanic vents with iron-rich lava, that there was erosion, and that at least in places the sea water was saturated with iron, and that there was probably a lot of CO2 in the atmosphere. Is that the entire picture of all conditions everywhere on the planet? Hell no - there could have been a spaceport and fancy resort hotel for a galaxy-spanning race of sentient slugs located in low earth orbit and we'd never know. However, whatever truly happened then must be consistent with those rocks in Quebec. Those rocks give an accurate picture of a very, very small field of view. Whatever else you want to claim, you must include that small, accurate bit of the picture and have that bit make sense. This constraint is true for every outcrop and every drill hole on the face of the planet, whatever the age of the rocks. Whatever truly happened must be consistent with every bit of the rock record.

Sure sounds like it to me. If we can't tell you what the entire planet was like, we don't have a 'clear and accurate picture', and hence don't know squat.

> That sounds more like an evolutionist referring to
> supernatural events. The evolutionists need the supernatural
> to conform to natural laws or nothing at all. Which discounts
> another entire set of laws and evidences albeit laws and
> evidences that are not fully understood yet.

Well, if it conformed to natural laws, then it wouldn't be supernatural now would it? So sort of by definition the supernatural is that which is physically or chemically impossible, right? Now, you seem to suggest that the supernatural follows certain laws, suggesting that supernatural events can be replicated, or at least that

> What it needs to be is consistent however. But scientific opinion
> often varies and sometimes will vary within the very same body of
> work. Case in point:
>
> In the first column:
> "3.8 billion years of simple cells (prokaryotes)"
>
> In the second and right columns:
>
> "4600 Mya: The planet Earth forms from the accretion disc revolving
> around the young Sun."
>
> "Dates prior to 1 billion years ago are speculative."
>
> So, The earth "forms" 4600 Mya /but/, we know for sure there was
> prokaryotes on a accretion disc revolving around the young Sun 3.8
> billion years ago? And in deep ocean volcanic vents no less?

Well, see, this is where things like the Nuvvuagittuq greenstone belt help out. The rocks at Nuvvuagittuq tell us unequivocally that by 4,280 million years ago the earth had solidified, had a crust, had water on that crust, and had a reducing atmosphere. Now, exactly how long those conditions had been going on is speculative (hence the qualification that 'dates before 1 billion years ago are speculative'), since we have no data to anchor dates any farther back, but the existence of earth and ocean from 4,280 million years ago to now is solid.

As to life, well, the evidence for biotic activity at 3.8 billion years ago is being questioned, I guess (see, for example, Brasier et al, 2006, A fresh look at the fossil evidence for early Archean cellular life, Phil. Trans. Roy. Soc. Lond. B Biol Sci, 361, pp.887-902; http://tinyurl.com/dy282v). However, we do have 3.5 billion year old stromatolites, which are unequivocal biogenetic fossils of sufficient complexity to suggest life had been around and cooking for quite some time at that point. Again, then, the date of the first self-replicator on earth is speculative, but we certainly have some solid bounds on it.

So what bothers you about this? That science continually critically evaluates and re-evaluates evidence? That we don't get it right the first time? That our knowedge is not absolute? Wake up and smell the coffee, my little chicken. You don't get absolutes in this life. You get good approximations sometimes, but no absolutes. Of course, this imposes a terrible responsibility on people: to do the best they can with insufficient data when the stakes are what is most important to them. Many folks simply cannot handle that responsibility and construct a fantasy world to inhabit where there are absolutes, and the choices are easy. That is fine as long as you don't insist that the real world is like that.

> http://en.wikipedia.org/wiki/Timeline_of_evolution
>
> ...
> Side Note:
>
> i never did put much faith in wikipedia anyway. It is only as accurate
> as the editors with the final say want it to be. But in this case, it
> just may be correct. What you guys do not want to face up to is that
> science can only guess. That's right. Guess. And those guesses are
> often based at times on flimsely evidences, personal intrepretations
> of those evidences; And, are subject to change when new evidences are
> found. However, these guesses are quite often presented as if they
> were comming from the burning bush. Some sort of truth. But we all
> know there can be only one burning bush, right? Disinformation,
> inconsistant information, wild guesses; a dishonest out of control
> news media pushing an agenda while reporting these guesses; they all
> give America a black eye to the a world that use to look to us for
> accuracy and stability.

> I have actually seen book author's cited in Wikipedia as if the
> conjecture and assertions in the books were a proven fact.

Hmm... I have seen that here, where some poor misguided souls cite pure fabrication as fact, like the 'fourteen foot thick layer of silt containing marine fossils' around the Pyramids, or 'high water marks on the exterior of the Pyramids'.^[1] Terrible, terrible. I agree, folks like that should be shot, or at least flogged.

> Such a slippery slope of disinformation America has gotten on; it is
> mind boggling to say the very least..

To which the answer is acceptance of self-contradictory 'ancient texts' as absolute truth? No thanks.

> Anyone actually believe mankind can establish what happened on earth 3
> or more BILLION years ago?
>
> I don't.

Does what we know limit what we may say about the unknown?

Post of the Month: April 2009