Or so they think at MSNBC. In “Can life evolve from a different chemical code?” (8/19/2011), Clara Moskowitz tells us, “Scientists ponder if life elsewhere is based on another set of amino acids.”
Other, that is, than the 20 – among hundreds – that build life’s known proteins:
“Life has been using a standard set of 20 amino acids to build proteins for more than 3 billion years,” said Stephen J. Freeland of the NASA Astrobiology Institute at the University of Hawaii. “It’s becoming increasingly clear that many other amino acids were plausible candidates, and although there’s been speculation and even assumptions about what life was doing, there’s been very little in the way of testable hypotheses.”
Along with colleagues, he discovered that
… life seemingly did not choose its 20 building blocks randomly.
“We found that chance alone would be extremely unlikely to pick a set of amino acids that outperforms life’s choice,” Freeland said.
So there is only one possible answer:
Natural selection
The story is,
“Here we found a very simple test that begins to show us that life knew exactly what it was doing,” Freeland said. “This is consistent with the idea that there was natural selection going on.”
No, it is not. Natural selection is blind to outcomes. That was the point, remember?
Turns out it’s “experimentally difficult” to find out any more.
We’ll be back here at origin of life in 1, 2, and 20 years. Same station, Same show. Same theme. Some new cast members.
Sure as heck some selection was going on.
Natural selection is teleological.
Since natural selection is, by definition, whatever happens happens, anything is consistent with the idea that there was natural selection going on.
Actually for natural selection you need, by definition, differential reproduction due to heritable (random) variation.
If you have differential reproduction due to something other than heritable (random) variation then you don’t have natural selection.
And if there isn’t any differential reproduction then you don’t have natural selection.
That said I would say the concept that “whatever happenes happens” applies to the theory of evolution (as in whatever survives to reproduce…)
The problem with applying natural selection to inanimate matter and energy is that nature would “select” a rock- simple to make and durable.
“Other, that is, than the 20 – among hundreds – that build life’s known proteins …”
There are now (*) 22 known amino acids coded by DNA … this is why the 64 DNA codons are no longer called “the universal DNA code”, but rather “the canonical DNA code”.
The discovery of the 21st amino acid coded by DNA codons shows the DNA code to *be* a code, such that it is not chemical necessity, but rather context and “syntax” which causes this codon to code for that amino acid.
(*) 22 is the latest number of which I am aware.
From the article you quote:
“So Freeland and his University of Hawaii colleague Gayle K. Philip devised a test to try to learn if the 20 amino acids Earth’s life uses were randomly chosen, or if they were the only possible ones that could have done the job.”
This was an analysis of physical and chemical attributes – not and assumption that NS acted but a search to see if there was something that NS could act on.
The post is misleading.
“If you have differential reproduction due to something other than heritable (random) variation then you don’t have natural selection.”
What confuses people is that most of the variation that we are familiar with isn’t random. It is already a product of several levels of selection, since what we see is usually a part of a functioning organism, at worst it wasn’t fatal at the meiotic or developmental levels or young adult levels at best and unlikely, it may be an obvious adaptive advantage, and usually it is just part of a mileau of accumulating variation having perhaps a minor influence on differential reproduction.
So . . . life chose life before it was life! Gotchya.
There is no fundamental difference between chance and natural selection. All chance processes operate through the filter of natural law. Increase the number of natural laws, does not get rid of chance, it just narrows down the possibilities. It always upsets me that Darwinists try to claim that NS is not random, when in fact it is.
The Strength of natural Selection in the Wild:
Or several levels of sheer dumb luck…