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New Findings Confirm Darwin's Theory — Evolution Not Random
ScienceDaily is reporting a team of biologists has demonstrated that evolution is a deterministic process, rather than a random selection as some competing theories suggested. "When the researchers measured changes in 40 defined characteristics of the nematodes' sexual organs (including cell division patterns and the formation of specific cells), they found that most were uniform in direction, with the main mechanism for the development favoring a natural selection of successful traits, the researchers said."
Hmm... I don't understand...
From what I picked up in bio, it was known to work as such:
Assume Mutation
(1) If mutation not hindrance, animal likely to live and likely makes babies.
(2) If mutation is boon, animal more likely to live and more likely makes babies.
(3) If mutation is hindrance, animal less likely to live and less likely to make babies
From there, you consider whether or not the mutation is recessive/dominant which determines if the babies get the mutation (then referred to as a trait).
Repeat many many times and you get a separation of a special line.
The proper combination of factors being: mutation = beneficial, mutation dominant, mutated animals screw like proverbial rabbits.
How is this different from the new findings?
Deterministic selection might be obvious. But can anyone offer an explanation how the very first instance of a successful trait comes about?
I have faith that the first instance of a long neck was due to one or more coincident random mutations.
yes. Natural selection is the mechanism that determines what survives. The Theory of Evolution includes this, but also encompasses other factors including mutation and/or genetic drift which introduce the differing traits that are acted upon by natural selection.
The theory of evolution includes the theory of the selection of advantageous traits, plus methods for the acquisition of new traits, like mutation.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
You are correct in describing facts and theories, but "evolution" can refer to both. This article explains it well I think - Evolution is a Fact and a Theory.
The article makes it sound like this proves that natural selection isn't a stochastic process, but in a couple of places they contradict this. It wouldn't make sense for natural selection to be deterministic.
My understanding of natural selection is that it's more or less a random walk with drift toward a point determined by the nature of the selection pressures. Reading between the lines, I'm guessing that this new research shows that the drift term of the process is much larger than the error term, not that there is no error term.
The significance of this would be that if the error term were large enough, the process would be unlikely to converge to the point determined by the selective pressure.
My only political goal is to see to it that no political party achieves its goals.
This is a link to the paper cited in the article:
http://www.current-biology.com/content/article/fulltext?uid=PIIS0960982207021938
Mutation is partly random, but selection definitely is not. Genes and traits are selected for by their ability to pass themselves on to the next generation. That's a criterion, not "randomness".
Note: mutation is definitely not always random, either. Organisms have developed extensive systems for modifying and altering how much mutation they incur, and what part of the genome receives those mutations. Look up, for example, the bacterial SOS response, in which bacterial colonies under stress will suddenly amplify their own mutation rate in the hopes that one or more of their member cells will "find a solution" to whatever the current stress and continue to survive. In addition, all organisms protect more critical parts of their genome from mutation to some degree. Truly important things like the region coding for ribosomal RNA and protein subunits tend to get very few mutations, because having a fucked-up ribosome is a death sentence.
Evolution itself is subject to evolution, and has been crafted to be less than perfectly random.
I stole this sig from someone cleverer than me.
Yes they are, at least for the standard dictionary definition of creationism:
creationism:
1. the doctrine that matter and all things were created, substantially as they now exist, by an omnipotent Creator, and not gradually evolved or developed.
2. the doctrine that the true story of the creation of the universe is as it is recounted in the Bible, esp. in the first chapter of Genesis.
Keep in mind, "Creationism" != "Religious faith". There are plenty of people who believe in God and who accept the scientific theory of evolution. But they are not creationists.
A hypothesis doesn't get called a theory until it has demonstrated substantial predictive power, and so is almost never found to be "incorrect" later. Instead conditions are discovered under which the old theory doesn't make useful predictions, and the new theory is "more general", or accurate to more decimal places, etc.
Socialism: a lie told by totalitarians and believed by fools.
Just to be clear, so we don't assume any misconceptions here about Einstein and religion:
I believe in Spinoza's God, Who reveals Himself in the lawful harmony of the world, not in a God Who concerns Himself with the fate and the doings of mankind. -- Einstein
It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it. -- Einstein
If a job's not worth doing, it's not worth doing right.
But the sources for relevant Wikipedia articles are credible primary sources. (Brian, Dennis (1996), Einstein: A Life, New York: John Wiley & Sons, p. 127, ISBN 0-471-11459-6) To save you some time, I've added some line breaks but retained the context.
Now for the second quote:
Wow, this is a triple convergence of a bad and confusing title, summary and article (which is a summary of the actual journal article) which is unusual even for slashdot.
This really isn't about Darwinian evolution which involves random mutations and selection of the favorable ones. However, there are some characteristics which are neither advantageous or disadvantageous. There is a debate about how many characteristics are "neutral". For example, did large noses appear because they are advantageous (for warming air perhaps) or because they just worked out that way by chance. So the original paper asked this question about worm vulvas and found that nearly all the characteristics that they looked at did NOT arrive by chance but were selected for (i.e. were advantageous in some way).
It is important to note both possible results would be consistent with Darwinian evolution. The only questions being addressed are the mechanism (does evolution go through mostly neutral phenotypes before a favorable phenotype is selected) and the extent that characteristics are neutral. For worm vulvas, it appears that the vulvas that form are biased towards the most favorable ones.
"In his encyclical Humani Generis (1950), my predecessor Pius XII has already affirmed that there is no conflict between evolution and the doctrine of the faith regarding man and his vocation, provided that we do not lose sight of certain fixed points....Today, more than a half-century after the appearance of that encyclical, some new findings lead us toward the recognition of evolution as more than an hypothesis. In fact it is remarkable that this theory has had progressively greater influence on the spirit of researchers, following a series of discoveries in different scholarly disciplines. The convergence in the results of these independent studies -- which was neither planned nor sought -- constitutes in itself a significant argument in favor of the theory." (John Paul II, Message to the Pontifical Academy of Sciences on Evolution) I believe most mainstream Christian faiths accept generally all mainstream scientific theories. Thermodynamics, gravity, electromagnetism, mechanics, biology..I think we're all on board. I don't see what should infuriate you about that. There are ignorant Christians who like to argue, and ignorant atheists who like to argue as well. They're both equally infuriating to reasonable people.
You offered a German proverb, I'll swap you an English one: you threw the baby out with the bathwater.
Hmm.
"When the proverb "Don't throw the baby out with the bath water" or its parallel proverbial expression "To throw the baby out with the bath water" appear today in Anglo-American oral communication or in books, magazines, newspapers, advertisements or cartoons, hardly anybody would surmise that this common metaphorical phrase is actually of German origin and of relatively recent use in the English language. It had its first written occurrence in Thomas Murner's (1475-1537) versified satirical book Narrenbeschwörung (1512) which contains as its eighty-first short chapter entitled "Das kindt mit dem bad vß schitten" (To throw the baby out with the bath water) a treatise on fools who by trying to rid themselves of a bad thing succeed in destroying whatever good there was as well. In seventy-six rhymed lines the proverbial phrase is repeated three times as a folkloric leitmotif, and there is also the first illustration of the expression as a woodcut depicting quite literally a woman who is pouring her baby out with the bath water.1 Murner also cites the phrase repeatedly in later works and this rather frequent use might be an indication that the proverbial expression was already in oral currency towards the end of the fifteenth century in Germany."
http://www.deproverbio.com/DPjournal/DP,1,1,95/BABY.html
Anyway, somehow I see it perfectly fits.
CC.
TaijiQuan (Huang, 5 loosenings)
Am not a biologist by trade, but had always thought evolution was at its root a random process. It has the potential to try anything, but known survival traits will always be favored.
We do understand the mechanism by which a trait will become dominant; reproduction of that built-in behavior to offspring. What we don't understand is how such dominance prevents other, competing traits from becoming active.
In the Science Daily excerpt, they mentioned long-necked giraffes, and how if evolution was random we would also see those of the short-necked variety.
This logic does not follow. We would see short-necked giraffes only if their survival let them reproduce. As they would tend not to - being unable to reach the leaves at the top of the tall trees, thus denying them the energy required to either attract a mate or carry offspring to term - this hitherto unknown mechanism would not favor that trait becoming dominant, though like the activities of a good pack rat, the DNA which would allow this trait to exist may continue to be stored, and passed - unused - on to future generations.
Thus, evolution hedges its bets. It may come to pass someday that the short-necked giraffe was more easily able to survive than their long-necked counterparts. Perhaps all trees become shorter. Perhaps some form of brittle bone disease kills the ones with longer necks, and they change their neck length and diet in order to survive. Perhaps they enter into a symbiotic relationship with some other creature that digs up food and leaves it on the ground. Who knows what the future will bring. But should conditions change, the potential for such a trait, still dormant within the species, may emerge to dominance.
This is not meant to introduce any talk of "design" into evolution, but the fact is our understanding of the system remains in the realm of how traits are passed on, not why.