posted on Oct, 30 2013 @ 07:15 PM
“When the Earth formed some 4.5 billion years ago, it was a sterile planet inhospitable to living organisms,” said Sankar Chatterjee, Horn
Professor of Geosciences and curator of paleontology at the Museum of Texas Tech University. “It was a seething cauldron of erupting volcanoes,
raining meteors and hot, noxious gasses. One billion years later, it was a placid, watery planet teeming with microbial life – the ancestors to all
OK basically he is saying that that meteors that once struck the earth not only brought the right ingredients needed to start building life they also
created the right habitats by punching holes through the crust creating those geothermal vents.
Us being in the goldilocks zone where water remains water those craters filled with water first. Imagine each crater as its own test tube. The thermal
vents as its heating source. Those thermal vents also added in the right mixture of elements to the process as well.
“For may years, the debate on the origins of life centered on the chemical evolution of living cells from organic molecules by natural processes.
Chatterjee said life began in four steps of increasing complexity – cosmic, geological, chemical and biological. By studying three sites containing
the world’s oldest fossils, he believes he knows how the first single-celled organisms formed in hydrothermal crater basins.
“The dual origin of the ‘RNA/protein’ world is more plausible in the vent environments than the popular ‘RNA world,’” he said. “RNA
molecules are very unstable. In vent environments, they would decompose quickly. Some catalysts, such as simple proteins, were necessary for primitive
RNA to replicate and metabolize. On the other hand, amino acids, from which proteins are made, are easier to make than RNA components.”
The question remains how loose RNA and protein material floating in this soup protected itself in a membrane. Chatterjee believes University of
California professor David Deamer’s hypothesis that membranous material existed in the primordial soup. Deamer isolated fatty acid vesicles from the
Murchison meteorite that fell in 1969 in Australia. The cosmic fatty bubbles extracted from the meteorite mimic cell membranes.
“Meteorites brought this fatty lipid material to early Earth,” Chatterjee said. “This fatty lipid material floated on top of the water surface
of crater basins but moved to the bottom by convection currents. At some point in this process during the course of millions of years, this fatty
membrane could have encapsulated simple RNA and proteins together like a soap bubble. The RNA and protein molecules begin interacting and
communicating. Eventually RNA gave way to DNA – a much more stable compound – and with the development of the genetic code, the first cells
the daily galaxy
Once those crater filled with water along with other materials brought by other meteors the environment is ready and the process begins. One of the
main ingredients to this is the fatty lipids because other scientists have shown they were probably instrumental in forming the first cells because
they form something like a cell membrane.
Here is how some of that may have worked.
Chemists show life on Earth was not a fluke
How life came about from inanimate sets of chemicals is still a mystery. While we may never be certain which chemicals existed on prebiotic Earth, we
can study the biomolecules we have today to give us clues about what happened three billion years ago.
Now scientists have used a set of these biomolecules to show one way in which life might have started. They found that these molecular machines, which
exist in living cells today, don’t do much on their own. But as soon as they add fatty chemicals, which form a primitive version of a cell membrane,
it got the chemicals close enough to react in a highly specific manner.
This form of self-organisation is remarkable, and figuring out how it happens may hold the key to understanding life on earth formed and perhaps how
it might form on other planets.
The 1987 Nobel Prize in Chemistry was given to chemists for showing how complex molecules can perform very precise functions. One of the behaviours of
these molecules is called self-organisation, where different chemicals come together because of the many forces acting on them and become a molecular
machine capable of even more complex tasks. Each living cell is full of these molecular machines.
Pasquale Stano at the University of Roma Tre and his colleagues were interested in using this knowledge to probe the origins of life. To make things
simple, they chose an assembly that produces proteins. This assembly consists of 83 different molecules including DNA, which was programmed to produce
a special green fluorescent protein (GFP) that could be observed under a confocal microscope.
Back to the main article.
The final stage – the biological stage – represents the origin of replicating cells as they began to store, process and transmit genetic
information to their daughter cells, Chatterjee said. Infinite combinations took place, and countless numbers must have failed to function before the
secret of replication was broken and the proper selection occurred.
“These self-sustaining first cells were capable of Darwinian evolution,” he said. “The emergence of the first cells on the early Earth was the
culmination of a long history of prior chemical, geological and cosmic processes.”
the daily galaxy
That part is a little harder for me to explain but it is pretty common theory of how life evolved from that point and is found in many theory’s.
He has built on other plausible theorems adding in more variables.
Chatterjee said. However, he suggested an experiment to recreate the ancient prebiotic world and support or refute his theory. “If future
experiments with membrane-bound RNA viruses and prions result in the creation of a synthetic protocell, it may reflect the plausible pathways for the
emergence of life on early Earth,”
I think his theory is worth testing it would be great if they get some positive results.
I see the beginning of earth as a giant testing ground that had billions of years to churn different scenarios out. For me it only makes sense that
eventually the right conditions would have been met to create life. The planet wasn’t placid it was alive in its own way with meteor strikes,
thermal vents, and seismic activity. Proof for that is we are here I would just like to see science recreate it.
edit on 30-10-2013 by
Grimpachi because: (no reason given)