by bohm 49 Replies latest jw friends
This discovery leads to one hypothesis: life in the Universe in much more exotic than it appeared in StarTrek, where 90% of all intelligent species were humanoid in appearance.
Dude, that's only because the Preservers spread humanoid life throughout the galaxy! They didn't evolve in situ; monogenesis not polygenesis. ;)
2) Can a bacteria based on arsenic, or some other element, evolve into a higher life form? If so, what would it look like / act like / be like?
According to this website, the resulting life form could be very...funny!
http://www.sfgate.com/cgi-bin/blogs/abraham/detail?entry_id=78240
For humans, arsenic pollution in groundwater has been a major problem. While a naturally occurring element, Arsenic can cause cancer in humans and "cardiovascular disease, diabetes, and neurological effects" according to the National Research Council. Moreover, Arsenic is found in cities and areas with smog and industrial emissions, and Mono Lake, which as far back as 2006 and beyond, has been noted for its air pollution problems.
Which brings us to Godzilla vs. The Smog Monster and the idea that we're a giant step closer to science fiction as fact.
Hedorah, or The Smog Monster, is a fictional character in the 1971 movie Godzilla vs. The Smog Monster. The Smog Monster grew from "microscopic tadpole-like organisms which began to feed upon the toxins with which mankind had poisoned its air and water."
A toxin like arsenic?
At any rate, the Wikipedia description of Hedorah gives a view of The Smog Monster's powers and abilities:
...Hedorah is capable of assuming a number of different shapes to suit the particular situation. For traveling through water, Hedorah transformed into a giant tadpole monster similar to the base organism that composed it. For traveling on land, Hedorah became a four-legged pile of slime resembling a gigantic salamander and it also could assume a saucer-like shape which granted it flight capabilities. After being driven back by Godzilla several times, Hedorah assumed a gigantic humanoid shape that even dwarfed the king of the monsters. Thanks to the protean nature of its body, ordinary weapons passed right through Hedorah while even Godzilla's atomic ray was unable to inflict any lasting harm. Finally, since Hedorah fed on pollution, so long as a piece of it remained alive then Hedorah could retreat to absorb more pollution in order to regenerate itself.
So, a possibility long considered to be far-fetched now has to be reconsidered. What, with respect to humans on Earth, is the possible logical conclusion of this new discovery? If a microorganism can exist feeding off a toxic chemical found in smog, what about another organism?
In other words, beyond life from other planets, what kind of new life are we causing to be created right here on Earth? Life that apparently exists from those chemicals which can kill people.
Stay tuned.
can live and thrive of arsenic.
Much different, and better, than that - it is an organism that is made of arsenic (among other elements).
If DNA analysis were available for the GB, I think you would find that they are part of this poisonous, toxic breed.
And in case you haven't heard....Reptilians drink blood mixed with arsenic.
Our world would likely be very toxic to an Alien with arsenic based dna. Just as well- we're overpopulated already.
This is very huge news. Not so much in that NASA now has to broaden their parameters in the search for ET life or life bearing environments, but in the implications for the origins of life here on earth.
Did that bacterium (as would be rational to assume) evolve here on earth in Mono Lake? Then how did that remarkable overhaul of its chemistry come about? Can they find molecular fossils that hint at the evolutionary paths taken?
Now, if its even different in the genetic code itself ( any mention of this at all? Is this known?) then its definitely alien to the rest of life on Earth. Maybe too much to ask for, but if that is also the case, then I'm going to strongly lean towards a dear idea for me...panspermia.
Yale Assistant Professor, Steven Novella. . .
What is entirely new with this discovery, however, is the fact that these bacteria, a strain (GFAJ-1) of a common type of bacteria called Gammaproteobacteria, appear to incorporate arsenic into their own biochemistry. In normal living cells phosphorous is used as part of the DNA and RNA backbone, in addition to being the energy transporting molecule (adenosine triphosphate), and being part of structural phospholipids. Arsenic is chemically similar to phosphate, and in fact that is partly the reason for its toxicity – it is very disruptive to normal biochemistry. These bacteria seem to have replaced phosphate with arsenic in some of these structures and molecules.
This is an important proof of concept – an alternate biochemistry in which arsenic replaces phosphate is possible.
This raises several interesting points. The one that NASA is primarily interested in is exobiology – life outside of earth. As the number of possible environments in which life can exist expands, so does the probable density of life in the universe and the chance that we will discover such life. The most common alternate biochemisty that I hear (whether in science fiction or speculation) is one in which silicon replaces carbon. Methane-breathers (using methane instead of oxygen for metabolism) is also common. Swapping arsenic for phosphorous now has to be added to the list.
Another interesting point is that “alien” life may exist on earth. So far, all life on earth that we have examined is biochemically similar and is clearly related – the result of one origin of life and subsequent evolution. But there is no reason why there cannot be multiple trunks to the tree of life on earth. Life may have arisen, or been seeded, multiple times. Clearly one origin now dominates, and may be exclusive, but there may be bacteria-like organisms on earth that are the remnants of other origins. Or, they may share a common origin with known life, but have branched off so much earlier than any known life that their biochemistry (even their DNA code) can be vastly different than anything known.
There are many thousands of species of bacteria that we have not yet fully investigated, so this possibility cannot be ruled out. We can conclude that if such a so-called shadow biome exists it must be rare, or else by chance alone we would have encountered it by now.
It can be argued that the discovery of extremophiles, especially this latest discovery, makes the discovery of “alien” bacteria on earth more unlikely because even in extreme environments bacteria that is related to the rest of life have pushed their way in. Perhaps the life that we know was so successful that it managed to invade every possible niche, crowding out any competitors.
Perhaps we will have to look beyond earth to discover the descendants of a truly independent origin for life. Such exploration is underway on Mars, and there are other candidates in our solar system, such as the moons Europa, Titan, and Enceladus. The primary way that we look for microbial life in such locations is by looking for the signs of biochemistry. This is precisely why NASA is interested in this research – they have to know what kinds of biochemistry to look for. This research may partly determine the kinds of experiments that future NASA probes will use to search for the signs of exobiology.
There aren't many discrete elements in the 4 nucleobases that make up DNA...just oxygen, hydrogen, and nitrogen. These are arranged in varying sequences of 4 nucleobases (adenine, guanine, thymine, cytosine) to make up one DNA "bit", or nucleotide. The 4 nucleobase "bits", however, are terminated and attached to other "bits" using phosphate bonds. So in total, that is just 4 elements.
I reread a book I have on DNA/RNA on this. The thing that strikes me is not the difference of substituting Arsenic for the single Phosphorus atom in each nucleotide - it is the apparant fact that the active part of the DNA - (the computer-code like pairing of the C, A, U, and G, the self-replication quality of this molecule, and the ability to code the production of protiens via the triads) - would appear to still be identical hydrocarbon formations and are remarkably similar to other earthly DNA.
Could it be that this is more a sign that primative construction of the DNA molecule and related protiens is really far more common than we realized in earthlike surroundings and can take place in an environment where Arsenic is common?
Still important, but not quite the alien quality of Michael Chrighton's "The Adromeda Strain" with its non-DNA living crystal forms.
I do agree that this gives a tremendous boost to the idea that alein life is out there. I have long held the view that life could be based on other matter besides carbon.
S
1) The GFAJ-1 bacteria is not "made of arsenic". There is some evidence that it may be able to incorporate a low amount of it into its own proteins, lipids and/or DNA.
2) The GFAJ-1 bacteria is carbon-based, as all known life is.
3) Arsenates are highly unstable in aquous (water) environment, and since cells contain mostly water, it is extremely unlikely that the GFAJ-1 bacteria that got to incorporate the arsenate into its metabolites are functional or viable.
There are many thousands of species of bacteria that we have not yet fully investigated,
Want some factual numbers? Biologists are able to culture only 2% of all bacteria species (of course, most of these are of medical/agricultural interest). That means that 98% of the microscopic world is still undiscovered.
