Exploring Life’s Origins

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protocell.jpgThe PT Crew received an email, announcing a breathtaking website called Exploring Life’s Origins. The website displays in stunning graphics and video how scientists are exploring the origins of life. The graphics were made by an NSF Discovery Corps Postdoctoral Fellow named Janet Iwasa, in collaboration with Jack Szostak, and the Current Science and Technology team at the Museum of Science, under an NSF grant. The resources are available under a Creative Commons License which requires attribution, non-commercial use and no derivative works. The website explains in clear and accessible language how science envisions life arose on earth and explains the RNA world, which, despite the wishful thinking of some creationists, has not lost its relevance.

As I said, the site explores in stunning graphics and video, the timeline of life’s evolution, the relevance of the RNA world and how one would build a proto cell. The site will help educators as well as other interested parties explore scientific scenarios explaining how life originated and evolved on our planet and present them as part of a science curriculum to their students.

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I was perusing the Panda’s Thumb blog, and I came across this post. It turns out that a new website, called Exploring Life’s Origins, has just been opened by the American Museum of Science. It’s a very nice website that has various gr... Read More

213 Comments

AWESOME. Very nice. Superb. Lab + Media. That’s just how I like it. :)

Any bets on how long before some of the graphics / video show up in a creationist movie?

Thanks PvM.

Doubleplus good.

The site says that photosynthesis only evolved once? Is that accurate?

The geologic record thus offers strong evidence for the evolution of oxygenic photosynthesis before 2800 Ma. There are, however, hints of even earlier origins. The microfossil record of cyanobacteria may extend to 3300 to 3500 Ma (22), although the evidence for these early Archean occurrences is controversial (23).

Source NASA

Abstract

Between 1 and 1.5 billion years ago [1 and 2], eukaryotic organisms acquired the ability to convert light into chemical energy through endosymbiosis with a Cyanobacterium (e.g., [3, 4 and 5]). This event gave rise to “primary” plastids, which are present in green plants, red algae, and glaucophytes (“Plantae” sensu Cavalier-Smith [6]). The widely accepted view that primary plastids arose only once [5] implies two predictions: (1) all plastids form a monophyletic group, as do (2) primary photosynthetic eukaryotes. Nonetheless, unequivocal support for both predictions is lacking (e.g., [7, 8, 9, 10, 11 and 12]). In this report, we present two phylogenomic analyses, with 50 genes from 16 plastid and 15 cyanobacterial genomes and with 143 nuclear genes from 34 eukaryotic species, respectively. The nuclear dataset includes new sequences from glaucophytes, the less-studied group of primary photosynthetic eukaryotes. We find significant support for both predictions. Taken together, our analyses provide the first strong support for a single endosymbiotic event that gave rise to primary photosynthetic eukaryotes, the Plantae. Because our dataset does not cover the entire eukaryotic diversity (but only four of six major groups in [13]), further testing of the monophyly of Plantae should include representatives from eukaryotic lineages for which currently insufficient sequence information is available.

Monophyly of Primary Photosynthetic Eukaryotes: Green Plants, Red Algae, and Glaucophytes, Current Biology , Volume 15 , Issue 14 , Pages 1325 - 1330

For the uninitiated, casual observer I offer the pdf file of the Thaxton Bradley exposition on the various theories of abiogenesis, including the RNA World, protocells, et al that successfully reduces these arguments to fanciful fairy tales regurgitated every decade or so by the grasping at straws evos.

http://www.themysteryoflifesorigin.org/

One must realize that these illusions and fabrications have no bearing on reality, actual primal conditions, and are reflective of the other-world of academics so well presented by Tom Wolfe in his essay “The Intelligent Coed’s guide to America”, that I heartily recommend as a companion piece to the scientific material.

Oh and for the quite curious who need a paper to pull the flush handle on this regurgitation there’s Kenyon and Mills paper: http://www.arn.org/docs/odesign/od1[…]world171.htm

and in 1993, Schopf produced evidence of microscopic cellular organisms nearly 3.5 billion years old, opening the floodgates to research that is filling in the holes in how and when life evolved on Earth.

“Everyone had expected that early organisms would be smaller, simpler, perhaps less varied, but they were universally thought to have evolved in the same way and at the same pace as later life,” Schopf writes. “This turned out not to be true. That evolution itself evolved is a new insight.” The pivotal point in evolution’s own evolution was the advent of sex about 1.1 billion years ago. The first organisms to engage in sexual activity were single-cell floating plankton, which, unlike organisms that reproduced by asexual division, like human body cells, had a pore-like mechanism that permitted the release of sex cells into the environment. Data from the fossil record clearly show that at about that time there appeared many new types of species. Sex increased variation within species, diversity among species and the speed of evolution and genesis of new species - bringing about not only the rise of organisms specially adapted to particular settings but also the first appearance of life-destroying mass extinctions.

“The pre-sex world was monotonous, dull, more or less static,” Schopf explains. “But every organism born from sexual reproduction contained a genetic mix that never existed before.”

What we don’t pay much attention to is that for most of life’s history, the biosphere was unicellar and for ca. 2 billion years prokaryotes.

Schopf who is a leading paleobiologist claims that the early fossils of bacteria and blue green algae look almost identical to what we could find in the nearest pond or beach today. The oldest stromatolites look like the newest as well. From there he implies that they are more or less the same.

Not being a specialist in micropaleontology, I can’t really evaluate these claims. But it does look possible that evolution snail paced for 2 billion years, picked up with the eukaryotes, and took off with the new kids on the block, metazoans. Part of this might have been because for billions of years until the earth rusted, oxygen was very low. And part of it might have been that the prokaryotes reached local optimums and never had any reason to go any further. Until evolution provided more diversity.

Sadly enough origins of life research has moved forward since thebook was written although from a historical perspective it is educational to watch how people considered the problem of abiogenesis. Ignorance seems to be a powerful motivator for ID Creationists.

Thanks Keith for an interesting link although it does not really help your case.

PS: Keith, is Thaxton’s work the only origin of life research with which you are familiar? Do you realize that the science has made giant leaps?

Why are you afraid to look?

keith said:

For the uninitiated, casual observer I offer the pdf file of the Thaxton Bradley exposition on the various theories of abiogenesis, including the RNA World, protocells, et al that successfully reduces these arguments to fanciful fairy tales regurgitated every decade or so by the grasping at straws evos.

What a grand intellectual our troll Keith is. … . Single handedly, he has bought down all of modern science.

All that, without any demonstrated knowledge whatever of biology, chemistry, geology, or physics.

What a guy!

… I offer the pdf file of the Thaxton Bradley exposition on the various theories of abiogenesis.…

Thaxton Bradley? He was the first editor of the legally-proven fraudulent and dishonest tripe known as “Of Pandas and People.” Tell me, are there any transitional phrases in this text of his as embarrassing as “cdesign proponentists”? Apart from the no-doubt many deliberate misinterpretations of abiogenesis research Laxton provides there’s got to be some unintentional “Tard” in there in somewhere.

… Kenyon and Mills paper…

Ah yes, from the infamous “Origins & Design” pseudo-journal. It’s a paper, but then so is toilet paper. Do you have anything from a real science peer-reviewed journal that’s up-to-date and not based on (misinterpreted) information from fifteen years ago.

The site says that photosynthesis only evolved once? Is that accurate?

wikipedia:

Photosynthetic bacteria do not have chloroplasts (or any membrane-bound organelles). Instead, photosynthesis takes place directly within the cell. Cyanobacteria contain thylakoid membranes very similar to those in chloroplasts and are the only prokaryotes that perform oxygen-generating photosynthesis. In fact, chloroplasts are now considered to have evolved from an endosymbiotic bacterium, which was also an ancestor of and later gave rise to cyanobacterium. The other photosynthetic bacteria have a variety of different pigments, called bacteriochlorophylls, and do not produce oxygen. Some bacteria, such as Chromatium, oxidize hydrogen sulfide instead of water for photosynthesis, producing sulfur as waste.

Evolution Plant cells with visible chloroplasts.The ability to convert light energy to chemical energy confers a significant evolutionary advantage to living organisms. Early photosynthetic systems, such as those from green and purple sulfur and green and purple non-sulfur bacteria, are thought to have been anoxygenic, using various molecules as electron donors. Green and purple sulfur bacteria are thought to have used hydrogen and sulfur as an electron donor. Green nonsulfur bacteria used various amino and other organic acids. Purple nonsulfur bacteria used a variety of non-specific organic molecules. The use of these molecules is consistent with the geological evidence that the atmosphere was highly reduced at that time.[citation needed]

Fossils of what are thought to be filamentous photosynthetic organisms have been dated at 3.4 billion years old.[8]

Good question. The oxygen producing photosynthesis evolved once because chloroplasts are captured cyanobacteria.

There are some odd bacteria called the green and purple sulfer bacteria and the imaginatively named green and purple nonsulfer bacteria that also photosynthesize. They use a pigment called bacteriochlorophyll. I’m not sure what the relationship is between cyanobacteria and the others, convergence or ancestor descendent.

waldtufel Wrote:

What a grand intellectual our troll Keith is. … . Single handedly, he has bought down all of modern science.

…along with all the creationist positions that contradict his. So who’s gonna break the news to the DI that their game of “don’t ask, don’t tell” is over?

Since the topic is early life (plants) it may interest some people - SCIENCEDAILY today has an article, “… Fundamental Building Block in Flowering Plants .….…”. “Biologists have discovered that a fundamental building block in the cells of flowering plants evolved independently, … on a separate branch of the evolutionary tree - in an ancient group called lycophytes that originated at about 420 m.yrs ago.”

Hard line darwinistic evolutionary theory along the lines of random mutations and natural selection, makes the flowering plants (angiosperms) the genetic descendants of the gymnosperms (seeds, no flowers -e.g., conifers).

It turns out that a “fundamental building block in the cells” was in the lycophytes 420 m. yrs ago, and it got involved in building flowering plants, some 300 m. yrs later. (Lycophytes as I dimly recall were about the level of club mosses). Standard Darwinism had these “fundamental building blocks” getting put together over time, courtesy of the gymnosperms. Turns out, it looks like it happened independent of the gymnosperms, although something very similar is in the gymno’s. Forgive the rough terminology. Genetics isn’t my major.

More “toolkits”, waiting to be activated by environmental triggering. See HOX genes in paddlefish, and so on.

That’s Owen’s information transforming Archtype, 1850, pre THE ORIGIN OF THE SPECIES.

Regarding the origin of life, suggest following along the same line. Information, marrying with organic structures. Same for photosynthesis. It only involves quantum level info.tech. so sophisticated it is not yet fully understood. Cheers.

PBH: That article refers to lignin, and a different form of lignin, albeit similar in general structure and function. It means that a similar hard-to-break-down plant chemical arose independently in two plant lineages, which argues for a similar base. Eyespots and photoreceptors form the base of a lot of chemical reactions in later metozoans, but it doesn’t imply that the photoreactive chemicals as a base were “planned” so eyes could develop. It means that making parts from other parts you have is easier, and sometimes results in the same thing happening twice - accidentally.

Applying an anthropomorphic “direction” template went out with Lamarckism in the late 19th century. Reading intent doesn’t prove intent - it proves you see intent by deriving from effect to cause. It also doesn’t preclude a non-intent driven cause as well.

PvM said:

Abstract

Between 1 and 1.5 billion years ago [1 and 2], eukaryotic organisms acquired the ability to convert light into chemical energy through endosymbiosis with a Cyanobacterium (e.g., [3, 4 and 5]). This event gave rise to “primary” plastids, which are present in green plants, red algae, and glaucophytes (“Plantae” sensu Cavalier-Smith [6]). The widely accepted view that primary plastids arose only once [5] implies two predictions: (1) all plastids form a monophyletic group, as do (2) primary photosynthetic eukaryotes. Nonetheless, unequivocal support for both predictions is lacking (e.g., [7, 8, 9, 10, 11 and 12]). In this report, we present two phylogenomic analyses, with 50 genes from 16 plastid and 15 cyanobacterial genomes and with 143 nuclear genes from 34 eukaryotic species, respectively. The nuclear dataset includes new sequences from glaucophytes, the less-studied group of primary photosynthetic eukaryotes. We find significant support for both predictions. Taken together, our analyses provide the first strong support for a single endosymbiotic event that gave rise to primary photosynthetic eukaryotes, the Plantae. Because our dataset does not cover the entire eukaryotic diversity (but only four of six major groups in [13]), further testing of the monophyly of Plantae should include representatives from eukaryotic lineages for which currently insufficient sequence information is available.

Monophyly of Primary Photosynthetic Eukaryotes: Green Plants, Red Algae, and Glaucophytes, Current Biology , Volume 15 , Issue 14 , Pages 1325 - 1330

But the site does not say the endosymbiotic event occured once, it says the chemical process evolved only once. Even before reading Wikipedia (thanks, raven!), I knew there were different ways of doing photosynthesis. This site seems to claim that they all evolved from one process.

Extremely nice. Should take time to go through it at leisure from home.

But it does look possible that evolution snail paced for 2 billion years, picked up with the eukaryotes

It certainly seems intuitively credible that the pace of morphologic evolution, however one proposes to measure it, must have increased exponentially after the certain thresholds were passed -

1) Multiploidy

2) Sexual reproduction, by which I mean, broadly, creation of genetically unique zygotes from parent cells.

The impact of these two things would be dramatic. Haploid prokaryotes can only pass on genetic material through mitosis and limited lateral transfer. They have little ability to tolerate variant alleles at any locus, since they can’t be “heterozygotes” in the sense that diploid organisms can. (They might have genes that overlap in function, or even two copies of the same gene at different loci, in rare cases, but that’s not the same thing.)

Of course, despite all this, prokaryotes, with short generation times, can evolve novel biochemical adaptations fairly quickly.

But the site does not say the endosymbiotic event occured once, it says the chemical process evolved only once.

wikipedia cyanbacteria:

The biochemical capacity to use water as the source for electrons in photosynthesis evolved once, in a common ancestor of extant cyanobacteria. The geological record indicates that this transforming event took place early in our planet’s history, at least 2450-2320 million years ago (Ma), and possibly much earlier. Geobiological interpretation of Archean (>2500 Ma) sedimentary rocks remains a challenge; available evidence indicates that life existed 3500 Ma, but the question of when oxygenic photosynthesis evolved continues to engender debate and research. A clear paleontological window on cyanobacterial evolution opened about 2000 Ma, revealing an already diverse biota of blue-greens. Cyanobacteria remained principal primary producers throughout the Proterozoic Eon (2500-543 Ma), in part because the redox structure of the oceans favored photautotrophs capable of nitrogen fixation. Green algae joined blue-greens as major primary producers on continental shelves near the end of the Proterozoic, but only with the Mesozoic (251-65 Ma) radiations of dinoflagellates, coccolithophorids, and diatoms did primary production in marine shelf waters take modern form. Cyanobacteria remain critical to marine ecosystems as primary producers in oceanic gyres, as agents of biological nitrogen fixation, and, in modified form, as the plastids of marine algae.[7]

Wikipedia says the same, referring to oxygen generating photosynthesis. No one may even know how the green and purple sulfer and green and purple nonsulfer photosynthetic bacteria fit in.

Hard line darwinistic evolutionary theory along the lines of random mutations and natural selection, makes the flowering plants (angiosperms) the genetic descendants of the gymnosperms (seeds, no flowers -e.g., conifers).

This isn’t necessarily true. There is substantial controversy on the placement of the angiosperms, including lots of recent DNA evidence that makes the gymnosperms monophyletic. If so, then gymnosperms and angiosperms are sister taxa.

Not to mention that there quite a few other lineages between clubmosses and angiosperms…

It turns out that a “fundamental building block in the cells” was in the lycophytes 420 m. yrs ago, and it got involved in building flowering plants, some 300 m. yrs later. (Lycophytes as I dimly recall were about the level of club mosses). Standard Darwinism had these “fundamental building blocks” getting put together over time, courtesy of the gymnosperms. Turns out, it looks like it happened independent of the gymnosperms, although something very similar is in the gymno’s.

The analogy to the evolution of flight in birds and bats is useful here. They resulted in similarities, but these similarities evolved separately. As is mentioned in the sciencedaily article you cite.

Hard line darwinistic evolutionary theory

Which is, of course, a straw man of your own construction.

Is anyone here able to field a really stupid question?

I’m looking at the picture of the “Formation of the moon” - the website states that it probably happened as a result of the earth and theia.

The picture looks like the impact created “round” planets. OK -here’s the dumb question … How is the “roundness” supposed to have happened? (Stop laughing OK - normally I would ask my husband, but he’s at work):-)

PvM,

The problem is that all the laws of chemistry and physics that obviate the recycled arguments presented by the phlogistonites haven’t changed. Further the referenced papers deal with each of the supposed elements of evidence in rather devastating ways.

See in critical thinking one doesn’t obscure or invalidate evidence based on its popularity, its age unless fully discredited with evidence, its newness, its adherents unless they have demonstrated experimental evidence.

Thaxton Bradley Laxton,,,I see we have some real intellects represented. LOL!

Charles B. Thaxton is a Fellow of the Discovery Institutes Center for Science and Culture. He has a doctorate in physical chemistry from Iowa State University. He went on to complete post-doctorate programs in the history of science at Harvard University and the molecular biology laboratories of Brandeis University.

Dr. Bradley is PhD Material Science prof retire d from Texas A&M while Olsen is a Geo-chemist. The concept of using multidisciplinary collaborators may be new to evos , but it’s really quite the norm.

As for peer review, the book was reviewed prior to publication by Dr. Dean Kenyon, one of the foremost researchers and authors in the field who wrote the foreword.

You people need some new material.

Stacy:

Gravity and heat. Of course they weren’t round right away, they settled into that shape. But I think that image is supposed to be of the actual colliding bodies, not the result.

Stacy:

The picture looks like the impact created “round” planets. OK -here’s the dumb question … How is the “roundness” supposed to have happened?

I presume you mean, roughly spherical? This is a good question.

Ordinary rocks as we know them here are solid because they’re held together ultimately by electromagnetic forces - atomic bonds. But as a rock becomes larger, eventually gravity becomes the overriding force. When gravity rules, then the rock assumes the most “efficient” shape - maximizes entropy. So it becomes a sphere much like water forms spherical globs on the space shuttle. The force of gravity is sufficient to override the atomic bonds.

Presumably at impact, the colliding bodies “splashed” one another also, so you had lots of small chunks coalescing back into globs. This would accelerate the rate at which those globs become spherical by breaking many bonds and reducing resistance to gravity.

So were they solid at the time of impact?

P.S. - I forgot to say Thank you to both of you. :-)

Stacy S. said:

So were they solid at the time of impact?

No, in fact the earth is still primarily molten. Near earth space was sprayed with debris from the impact. This debris collected to form the moon or fell back to earth, or escaped the local gravity, or impacted the earth or moon during subsequent orbits.

The planets crust is very thin compared to its radius. If a large impact occured today, it would still reform into a sphere.

The earths core contains a nuclear furnace that heats the mantle, which gives us the magnetic field, which protects the atmosphere and oceans from being stripped by the solar wind. Should the earth become solid, most if not all higher forms of life would perish.

Disclaimer: I’m not a geologist nor have I played one on TV. However, I did stay at a Holiday Inn last night :)

OK - LoL! That explains it! Thank you!

Stacy S. said:

Is anyone here able to field a really stupid question?

I’m looking at the picture of the “Formation of the moon” - the website states that it probably happened as a result of the earth and theia.

The picture looks like the impact created “round” planets. OK -here’s the dumb question … How is the “roundness” supposed to have happened? (Stop laughing OK - normally I would ask my husband, but he’s at work):-)

Don’t laugh, I know of the hypothesis, but I can’t answer the question. I’ll be interested in the answer.

dpr

windar 007 said:

Don’t forget Stacy, darwinists say people, animals and plants all came from rock (i.e. the alleged primal earth).

If you actually knew how to read, you would have known that evolutionary biologists and other scientists who study Abiogenesis say that life arose in a water-filled environment, such as the Ocean, due to ammonia and simple carbon-based molecules, such as methane and ethane, reacting, combining, decomposing and recombining to form more complex organic molecules and compounds. Some scientists have suggested that life arose on the surface of pyrite crystals, zeolite minerals, or clay, given as how these substances have been observed to aggregate organic compounds onto their surfaces very readily.

“The origin of animals [like … pandas] is almost as much a mystery as the origin of life itself.” - P.C.J. Donoghue, Embryonic identity crisis, Nature v 445, Jan. 11, 2007, p. 155

So what if the origin of animals is mysterious? What are you trying to say with your little quotemine? That, because trying to understand how animals relate to other organisms is too hard for you to understand, human civilization should stop studying Biology all together? Am I to presume that you wouldn’t mind watching people, whether you know them or not, die from diseases that could have been cured, or that you wouldn’t mind starving to death because the agricultural industries can’t produce anymore food due to having no more science to support them?

As for the Moon’s origin, atheists have their idea of the lunar collision “4.5 billion yrs ago” by a Mars-sized object. But there’s a serious problems with this regarding how a ring of debris actually will come together into a moon. Other physical problems include earth’s Roche limit (Lissauer, 1997). “There is no strong geochemical support for either the Giant Impact or Impact-triggered Fission hypothesis (Ruzicka, A, et al., International Geology Review 40, 1998). There’s also the problem of lunar heat. In 1965 Gamow (p. 41-42) said the moon must be cold throughout. But lunar mapping by the Clementine satellite showed, “Most likely, part of the rock is still molten” (Kerr, Science 264:1666).

Among other things, this is a topic of Geology, not Atheism, and two, did it ever occur to you that scientists change their minds when they encounter new evidence, and that scientists will have encountered a lot of new evidence within the span of a decade or 5?

It’s almost like the Moon was created, Stacy. There’s a consistent sequence of integer numbers when looking at every major aspect of the moon. Not so with other moons or planets in our solar system.

Did it also occur to you that there are other hypotheses on how the Moon was formed?

What evidence do you have to show that the Moon was magically created out of nothing 6000 years ago? A plaque found by astronauts reading “GOD MADE THIS MOON ON 4004BC”?

And some advice, windar: please don’t bandy the term “atheist” around in the exact same manner a truckdriver uses the term “fag,” especially when you mean to say “scientist.” Among other things, not all scientists are atheists, and not all atheists are scientists, and it makes you look like a bigot, as well as an anti-intellectual.

(Sigh). No. Biochemists - not “darwinists”, there’s no such thing - mostly say that life probably began through the action of solar energy on organic molecules in a mildly reducing atmosphere. Notice the qualifiers, because unlike someone whose opinions were grafted on them in childhood, the scientists don’t know for sure. The evidence, a concept with which windar 007 is unfamiliar, is scant and difficult to interpret. They’re working to find out, though. There are several possible explanations.

As for the moon, which is apparently devoid of life, biochemists and biologists have nothing to say at all. The question of how it got there doesn’t concern them, in a professional sense, though no doubt they are curious, as scientists are generally. But most scientists have the elementary good sense not to comment on matters they know nothing about.

For what it’s worth, the origin and history of the earth’s moon is not known. There are several competing theories among astrophysicists and astronomers. But just because the moon’s origins are not known doesn’t mean that one fine day God decided to give the earth a moon and poof, there it was. God seems mostly to work through natural processes and reasonable causation. I don’t know why windar 007 thinks the moon’s an exception.

Yeah, it’s that other book that says life came from rock (dust = crushed rock).

On the other hand, most of the molecules in our bodies probably were part of some rock at some time in the past. ;)

Henry

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This page contains a single entry by PvM published on May 28, 2008 1:00 PM.

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