Teaching Evolution

I'm simply pointing out that there are some serious leaps in logic in explaining the "creation" of things. It seems that many insist that things are just so, but can offer nothing much to demonstrate the mechanism by which, for instance, one of the most complicated widgets in the galaxy - the DNA helix - can emerge, entirely undirected, from the primordial soup - other than - by God, it just "happened," or the statistics indicate . . . Or by weaving remarkably poetic pictures of the caldron of creation with all that heat and those anxious gasses and hellfire and pressures and volcanoes and the dad-burn helix crept outta the mud because it took it's sweet time, like billions of years, and accomplished it's goal by way of indescribably small steps, and failed a gazillion times, but it just happened anyhow because . . . . And how stupid I am and not understanding the complexity of evolution because the fosile record says this and that.

And no, I'm not suggesing that an external Intelligent Design model or Big Dad in the sky directed the whole shebang. I am simply, as usual, just raising questions that pester me.

Simply because there are fundamental elements in motion, they will bump into each other and quite possibly bond as their properties allow and through a billion different combinations they might end up in complex combinations that survive or not according to various factors. However in the real world, the one we live in, which is strictly a material world according to some, remarkably complex things never simply organize themselves without some internal or external direction and most of all, without some intentionality. What we have here is a thesis saying that this intentionality and the mechanism by which the helix arose are the same things, meaning the intentionality and matter are not separate, just as gravity does not exist separate from matter.

At this point it would seem that mater has inherent intentionality. The sticking point is to insist that this inherent intentionality has no inherent smarts or intelligence, but can produce, by way of blind chance, something that we, with all our brain power, could only understand and appreciate in recent times. And then to go on and say, Ain't it grand, how Nature simply does this "on it's own." It is this "on it's own," with the implication that there is no intelligence or intentionality at play, that makes me wonder, considering the complexity of life. What does this, "on it's own," actually mean?

I'm not saying this is not so - as unlikely as it seems - but if it did, it is so miraculous that it makes Jesus Christ walking on water look like a 5.1 slab.

JL

I suppose if one wanted, he could personify a Na atom and a H20 molecule and then say they "intend" to get together or that they "desire" to get together to make sodium hydroxide. In this manner of speaking, the matter (of Na and H20) would have "intentionality."

predates when natural selection would kick in

Few scientists think life did the leap straight to DNA.

For real? Who is actually taking this seriously?

Largo: For real? Who is actually taking this seriously?

August 30, 2011

Antarctica Meteorite Hints at Extraterrestrial Origins for Prebiotic Molecular Evolution

Ammonia found in a carbon-containing meteorite from Antarctica adds to a growing body of evidence that meteorites may have played a key role in the development of life here. The NASA image above below was released early this year, when researchers reported that meteorites may have also delivered Earth’s first left-hand amino acids.

“Given that meteorites and comets have reached the Earth since it formed, it has been proposed that the exogenous influx from these bodies provided the organic inventories necessary for the emergence of life," said lead researcher Sandra Pizzarello, of Arizona State University.

The carbonaceous meteorites of the Renazzo-type family (CR) are known to be especially rich in small soluble organic molecules, such as the amino acids glycine and alanine. To test for the presence of ammonia, the researchers collected powder from the much-studied CR2 Grave Nunataks (GRA) 95229 meteorite and treated it with water at high temperature and pressure. They found that the treated powders emitted ammonia, NH4, an important precursor to complex biological molecules such as amino acids and DNA, into the surrounding water

The researchers then analyzed the nitrogen atoms within the ammonia and determined that the atomic isotope did not match those currently found on Earth, eliminating the possibility that the ammonia resulted from contamination during the experiment. Researchers have struggled to pinpoint the origin of the ammonia responsible for triggering the formation of the first biomolecules on early Earth. It now appears that they have found it.

“The findings appear to trace CR2 meteorites’ origin to cosmochemical regimes where ammonia was pervasive, and we speculate that their delivery to the early Earth could have fostered prebiotic molecular evolution,” they write.

DNA Building Blocks Found in Carbon-Rich Meteorites

A team of GCA scientists M. Callahan, J. Stern, D. Glavin. J. Dworkin and their co-investigators found diverse suite of nucleobases and terrestrially rare nucleobase analogs in twelve carbon-rich meteorites. These include denine and guanine, as well as hypoxanthine and xanthine DNA resembles a spiral ladder; adenine and guanine connect with two other nucleobases to form the rungs of the ladder. They are part of the code that tells the cellular machinery which proteins to make. Hypoxanthine and xanthine are not found in DNA, but are used in other biological processes. The discovery adds to a growing body of evidence that asteroids and meteorites are chemical 'factories' that may have been important sources of organic compounds required for the emergence of life on the early Earth. The discovery of new nucleobase analogs in meteorites also expands the prebiotic molecular inventory available for constructing the first genetic molecules. 08.08.11

Variations of Gas Release from Comet Hartley-2

GCA scientists, Drs. Mumma, Bonev, Villanueva, Paganini, DiSanti and an international team of co-investigators measured episodic and spatial variations of eight primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, C2H2, H2CO, and NH3) and two product species (OH and NH2) in comet 103P/Hartley 2 using high-dispersion infrared spectroscopy with large ground-based telescopes in Hawaii and Chile. The primary species were released directly from the comet nucleus, while the product species were produced in the coma. The team quantified the long- and short-term production rates of these volatiles over a three-month interval from October to December 2010 that encompassed the comet’s close approach to Earth, its perihelion passage, and flyby of the comet by the Deep Impact spacecraft during the EPOXI mission. The short-term variations were consistent with nucleus rotation when compared with other observations. These measurements helped to determine the composition of Hartley-2, which is the only comet from the Kuiper Belt to be so categorized. 5.17.2011

NASA Researchers Make First Discovery of Life's Building Block in Comet - 08.17.09

NASA scientists have discovered glycine, a fundamental building block of life, in samples of comet Wild 2 returned by NASA's Stardust spacecraft.

"Glycine is an amino acid used by living organisms to make proteins, and this is the first time an amino acid has been found in a comet," said Dr. Jamie Elsila of NASA's Goddard Space Flight Center in Greenbelt, Md. "Our discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago by meteorite and comet impacts."

Elsila is the lead author of a paper on this research accepted for publication in the journal Meteoritics and Planetary Science. The research will be presented during the meeting of the American Chemical Society at the Marriott Metro Center in Washington, DC, August 16.

"The discovery of glycine in a comet supports the idea that the fundamental building blocks of life are prevalent in space, and strengthens the argument that life in the universe may be common rather than rare," said Dr. Carl Pilcher, Director of the NASA Astrobiology Institute which co-funded the research.

Proteins are the workhorse molecules of life, used in everything from structures like hair to enzymes, the catalysts that speed up or regulate chemical reactions. Just as the 26 letters of the alphabet are arranged in limitless combinations to make words, life uses 20 different amino acids in a huge variety of arrangements to build millions of different proteins.

Stardust passed through dense gas and dust surrounding the icy nucleus of Wild 2 (pronounced "Vilt-2") on January 2, 2004. As the spacecraft flew through this material, a special collection grid filled with aerogel – a novel sponge-like material that's more than 99 percent empty space – gently captured samples of the comet's gas and dust. The grid was stowed in a capsule which detached from the spacecraft and parachuted to Earth on January 15, 2006. Since then, scientists around the world have been busy analyzing the samples to learn the secrets of comet formation and our solar system's history.

"We actually analyzed aluminum foil from the sides of tiny chambers that hold the aerogel in the collection grid," said Elsila. "As gas molecules passed through the aerogel, some stuck to the foil. We spent two years testing and developing our equipment to make it accurate and sensitive enough to analyze such incredibly tiny samples."

Earlier, preliminary analysis in the Goddard labs detected glycine in both the foil and a sample of the aerogel. However, since glycine is used by terrestrial life, at first the team was unable to rule out contamination from sources on Earth. "It was possible that the glycine we found originated from handling or manufacture of the Stardust spacecraft itself," said Elsila. The new research used isotopic analysis of the foil to rule out that possibility.

Isotopes are versions of an element with different weights or masses; for example, the most common carbon atom, Carbon 12, has six protons and six neutrons in its center (nucleus). However, the Carbon 13 isotope is heavier because it has an extra neutron in its nucleus. A glycine molecule from space will tend to have more of the heavier Carbon 13 atoms in it than glycine that's from Earth. That is what the team found. "We discovered that the Stardust-returned glycine has an extraterrestrial carbon isotope signature, indicating that it originated on the comet," said Elsila.

The team includes Dr. Daniel Glavin and Dr. Jason Dworkin of NASA Goddard. "Based on the foil and aerogel results it is highly probable that the entire comet-exposed side of the Stardust sample collection grid is coated with glycine that formed in space," adds Glavin.

"The discovery of amino acids in the returned comet sample is very exciting and profound," said Stardust Principal Investigator Professor Donald E. Brownlee of the University of Washington, Seattle, Wash. "It is also a remarkable triumph that highlights the advancing capabilities of laboratory studies of primitive extraterrestrial materials."

The research was funded by the NASA Stardust Sample Analysis program and the NASA Astrobiology Institute. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Stardust mission for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, developed and operated the spacecraft.

To learn more about the mission, visit http://stardustnext.jpl.nasa.gov/ .

Dr. F: I have problems accepting that Life could have come from a meteorite or planted here by aliens. No life can make it through a descent into the atmosphere and not burn up into dust.

I have problems accepting that Life could have come from a meteorite or planted here by aliens.

No life can make it through a descent into the atmosphere and not burn up into dust.

Life wasn't created.

"we haven't completely figured out yet."