And just in case you think I am talking only about Homo sapiens, you are wrong. We are neither the end result of evolution nor the highest and best use of evolution, just another example of evolution - and one which is surely not long for this world. There is no reason why we should not follow the same fate as 99.9% of all the other species that once lived on the planet.
"We are neither the fastest nor the strongest of creatures. We're not even the most prolific: in terms of biomass, ants are more plentiful, and they've been around much longer..." (Frank T. Vertosick, Jr., The Genus Within - 2002)
Science and the natural law of science rules life and everything in the universe. Although it is also quite possible that natural law may be different elsewhere in the universe and different galaxies and multiverses may have varying natural laws different than our own.
Just as the extreme right wing has been anti-science, for far too long an extremist "radical" political left has resisted science preferring a more idealized romantic world view where everyone has a greater potential for doing good. That may be the ideal view but it is not the right view. The potential all of us have is the biological imperative to reproduce. And biological organisms that survive to reproduce get to provide DNA to the next generation of survivors. That is all there is. Everything else is window dressing.
"So the tendency toward slaughter that manifested itself in the Chinese Cultural Revolution is not the product of agriculture, technology, television, or materialism. It is not an invention of either Western or Eastern civilization. It is not a uniquely human proclivity at all. It comes from something both sub- and super- human, something we share with apes, fish, and ants--a brutality that speaks to us through the animals in our brain. If man has contributed anything of his own to the equation, it is this: He has learned to dream of peace. But to achieve that dream, he will have to overcome what nature has built into him." (Howard Bloom, The Lucifer Principle - 1995)
Life is basically a simple idea but complex enough to add wonderment and awe to it. We can't help but be humble in the presence of nature's wonderment and great majesty.
AT first RNA did rule our world. BUT there were complications. There there was DNA. DNA replicates but cannot do so unassisted. Replication needs proteins which are large molecules chemically different from DNA. And proteins, like DNA are built of subunits of amino acids in a long chain. It is the business of each cell to put to work 20 of these amino acids, which are called building blocks, to form the proteins.
So where did these amino acids come from? What is the origin of amino acids? See "The Origin of Life on the Earth," by L. E. Orgel; Scientific American, October 1994., the Stanley Miller experiment first published in 1953 where he applied a spark to a mix of gases resembling early conditions on Earth out of which two amino acids of the 20 were formed. Also see info re: Murchison meteorite, which impacted with Earth in 1969, in which 80 amino acids were found, out of which were ample building blocks, i.e. nucleotides, for the formation of life. "By extrapolation of these results, some writers have presumed that all of life's building could be formed with ease in Miller-type experiments and were present in meteorites and other extraterrestrial bodies. This is not the case." (Source: Scientific American)
Amino acids make proteins. These proteins do a variety of tasks, they are the _handymen_ of living cells. But it doesn't end there. The handymen; that is, the proteins need enzymes, which are _expeditors_ which hasten chemical processes, making them useful for life.
It is the DNA which contains the recipe for the construction of the protein which cannot be copied or retrieved.
Enter RNA, a class of molecule, like the DNA which is assembled in a helix of nucleotide (protein) building blocks. RNA resembles DNA but it is the molecule which edits and censors DNA code (instructions).
There are clues that RNA appeared before proteins and DNA in the evolution of life. There are small molecules, called _cofactors_ which perform enzyme-catalyzed reactions and they carry an attached nucleotide with no known function, so some scientists have speculated that they are _molecular fossils_ - that is, they are relics descended when RNA alone, without DNA ruled the natural biochemical world. We don't really know for sure, therefore it is just a hypothesis (though it is a good one) that life began with RNA alone.
And what happened before RNA? There are still many questions we cannot answer and until there are answers to these and other questions much of it will be attributed to an intelligent designer because being inexplicable the natural course for those who do not have an answer is to invent one and attribute all things inexplicable to the super-inventor of everything, to that mysterious supernatural thing referred to as GOD. That isn't really an answer for anything but it is the meme most humans adopt as reasonable. And it is difficult to impossible to debate the existence of god, no matter how unreasonable the belief in a belief is - with those committed to that belief. How did that first self-replicating RNA arise? What made RNA? Are Did RNA just emerge out of gray-green goo?
There are opposing views (Miller experiment) and what has been found in meteors is sufficient to produce the basic Watson-Crick building blocks necessary for life.
The Scientific American reported that analysis of "several meteorites led the scientists who conducted the work to a different conclusion: inanimate nature has a bias toward the formation of molecules made of fewer rather than greater numbers of carbon atoms, and thus shows no partiality in favor of creating the building blocks of our kind of life. (When larger carbon-containing molecules are produced, they tend to be insoluble, hydrogen-poor substances that organic chemists call tars.) I have observed a similar pattern in the results of many spark discharge experiments."
"Amino acids, such as those produced or found in these experiments, are far less complex than nucleotides. Their defining features are an amino group (a nitrogen and two hydrogens) and a carboxylic acid group (a carbon, two oxygens and a hydrogen) both attached to the same carbon. The simplest of the 20 used to build natural proteins contains only two carbon atoms. Seventeen of the set contain six or fewer carbons. The amino acids and other substances that were prominent in the Miller experiment contained two and three carbon atoms. By contrast, no nucleotides of any kind have been reported as products of spark discharge experiments or in studies of meteorites, nor have the smaller units (nucleotides) that contain a sugar and base but lack the phosphate." (ibid)
"To rescue the RNA-first concept from this otherwise lethal defect, its advocates have created a discipline called prebiotic synthesis. They have attempted to show that RNA and its components can be prepared in their laboratories in a sequence of carefully controlled reactions, normally carried out in water at temperatures observed on Earth. Such a sequence would start usually with compounds of carbon that had been produced in spark discharge experiments or found in meteorites. The observation of a specific organic chemical in any quantity (even as part of a complex mixture) in one of the above sources would justify its classification as "prebiotic," a substance that supposedly had been proved to be present on the early Earth. Once awarded this distinction, the chemical could then be used in pure form, in any quantity, in another prebiotic reaction. The products of such a reaction would also be considered "prebiotic" and employed in the next step in the sequence." (ibid)
In any event the controversy is far from being resolved at this point in time and any further explanation of the RNA first argument is way above my pay grade but I wanted to at least lay out the essense of the conflict which persists for this conundrum.
I think it is unfortunate that many of those who favor an Intelligent Design approach will use this as an example of the scientific inability to explain life.
There have been numerous other theories proposed for RNA or RNA type substances playing a role in the origin of life on Earth. Most of these theories vis-a-vis prebiotic Earth also rely on hypothetical presumptions that Nucleotide Watson-Crick base pairs type replication was used in the formation of life in prebiotic Earth. It has not been possible to reproduce life using scientific experimentation; at least not so that cytosine can be created, one of the four molecules necessary for the Watson-Crick base for ATCG. Nor has Cytosine been found in any analysis of meteorites or products of spark discharge experimentation. It has been suggested that on the basis of evidence or the lack thereof, it is unlikely that cytosine played a role in the origin of life. However, theories that involve replicators that function without the Watson-Crick pairs, or no replicator at all also remain as viable alternatives.
Hank Roth
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