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Darwinian Evolution Considered As a Phase
LucidBeast tips a mind-bending report at New Scientist on the latest paradigm-breaking work of Carl Woese, one of whose earlier discoveries was the third branch of life on Earth, the Archaea. Woese and physicist Nigel Goldenfeld argue that, even in its sophisticated modern form, Darwin's theory of evolution by natural selection applies only to a recent phase of life on Earth. Woese and Goldenfeld believe that horizontal evolution led to the rise of the genetic code itself. "At the root of this idea is overwhelming recent evidence for horizontal gene transfer — in which organisms acquire genetic material 'horizontally' from other organisms around them, rather than vertically from their parents or ancestors. The donor organisms may not even be the same species. This mechanism is already known to play a huge role in the evolution of microbial genomes, but its consequences have hardly been explored. According to Woese and Goldenfeld, they are profound, and horizontal gene transfer alters the evolutionary process itself."
The first 2 parts of Spore are like Horizontal Evolution, and the later parts are all vertical.
It makes perfect sense. Clearly Will Wright is a genius.
You know, scientists just keep reforming their ideas until it conforms to observable reality. How can they expect anyone to believe what they say when they're just going to keep changing their minds?
I prefer my religion. It allows me to conform reality to my ideas.
I pass on my genes horizontally
Watch those corners
This really isn't entirely new; Dawkins' book The Selfish Gene is based around the idea that it's individual genes that are selected for, not organisms.
. . . you're better off doing it vertically.
Wearing running shoes.
And ideally permission of the farmer.
(beat)
What?
For those who do not care to register for that New Scientist, we still have arXiv... :)
http://arxiv.org/abs/q-bio/0702015
Paul B.
However, I've always read Darwinian evolution as "survival of the fittest", with no qualifier as to how you go about surviving.
"Survival of the fittest" aka Natural Selection was half of Darwinian evolution. This was the half about how traits were selected for in the environment.
The other half was how an organism's traits came about, and his theory was that traits were passed from parents to offspring in the reproductive cells via some biological mechanism that allowed for combination and mutation. Eventually we discovered DNA, the very biological mechanism in question that had traits like Darwin predicted (though Mendel was the one who really nailed down the probably behavior of this then-unknown mechanism).
"Horizontal" evolution doesn't fall into that category, though. So it's not "Darwinian". Even though natural selection (obviously) still applies to what gene transfers result in successful organisms.
As the summary mentions, this is well known in micro-organisms. In fact as far as I can tell they aren't arguing that it applies to anything but microorganisms. The argument seems more like that because these are the most common life forms on earth and also the oldest, Darwinian evolution is not the most common or dominant form of evolution.
Which is a good point. Though really, as far as what affects us and other sexually reproducing creatures, Darwinian evolution is still 'it' more or less. The real importance of this breakthrough is in studying how the evolutionary mechanisms themselves evolved -- evolution is of course not immune to evolution. ;) This is going to be a powerful way of thinking about how early aspects of DNA came to be.
But just to be clear -- if someone says that this proves Darwin was wrong, evolution is a sham, and therefore their beliefs are probably right, go ahead and slap them. :) All this means is that evolution is even more complicated and powerful than previously thought.
The enemies of Democracy are
Here's a tip, folks. The minute you see some science journalist use the word "paradigm", as in "paradigm shift" or "paradigm breaking" you can be quite certain that what follows will be neither.
Horizontal gene transfer has been known about for decades, and the notion that the root of the tree of life is more a tangle of interconnecting branches has pretty much been accepted for some time now. We know that particularly with prokaryotes, horizontal transfer happens, and that while more difficult with eukaryotes, can still happen (ie. endo-retroviral insertions). It is yet another facet of evolution, not some independent force.
The world's burning. Moped Jesus spotted on I50. Details at 11.
I can't read the article without registering but I wonder if homosexual behavior could be causing horizontal gene transfer in humans, possibly using viruses as a transport mechanism.
If viruses are your transport mechanism, I'm not sure you need homosexual behaviour. You may, yes, but there are plenty of other mechanisms for viruses to spread.
Horizontal transfer isn't really over, either - we still have retroviruses.
Have Woese and Goldenfeld a brilliant new idea? All they're saying, I think, is that "parent" and "child" are the appropriate units of selection only when genes are passed vertically: from parent to child. They're suggesting that horizontal gene transfer is underrated as a historical evolutionary force.
Agree or not, it hardly undermines Darwin. Genes weren't known in the 19th century. Darwin didn't have a clue about genes, so we're gonna knock him for being "wrong" about it? I mean, was Jesus wrong about genes, too? It's anachronistic silliness.
Science is fundamentally dynamic. Any science that hasn't progressed in 150 years ain't doing too well. (Dear creationists: stop calling us "Darwinists." We've moved on.) I mean, The Origin came out in 1859, for crying out loud! Darwin was more brilliant, more insightful, and rightly more famous than I'll ever be. But if we both had to take a biology test right now, I'd kill him.
I saw an article recently about a species of snail that has acquired the genes for making chlorophyll from the algae it eats. It hasn't yet acquired the genes to make chloroplasts, so it has to eat algae to get enough chloroplasts from the algae to allow photosynthesis to work, but after that it is capable of living with no food other than light.
So, obviously this is still ongoing, and on larger scales than microbes.
"I do not agree with what you say, but I will defend to the death your right to say it"
There are instances of proteins evolving into something that does something different.
"Biologists have shown that independent but similar molecular changes turned a harmless digestive enzyme into a toxin in two unrelated species -- a shrew and a lizard -- giving each a venomous bite."
http://www.sciencedaily.com/releases/2009/10/091029125532.htm
Generally, what happens in these cases (where a protein evolved into a different protein with a different function) is that the original DNA sequence gets duplicated, and then one of the duplicates starts evolving (and the other copy continues to serve the same original function that it had earlier). One of the things that evolutionary biologists do is look at protein sequences and find similar sequences within the same organism. Very often, there's a tree-like structure showing multiple variations on a single protein within an organism. For example, humans have multiple copies/variations on the hemoglobin gene. They're either inactive or active at different phases in a person's life. Example:
"Fetal hemoglobin, or foetal haemoglobin, (also hemoglobin F or HbF) is the main oxygen transport protein in the fetus during the last seven months of development in the uterus and in the newborn until roughly 6 months old. Functionally, fetal hemoglobin differs most from adult hemoglobin in that it is able to bind oxygen with greater affinity than the adult form, giving the developing fetus better access to oxygen from the mother's bloodstream."
http://en.wikipedia.org/wiki/Hemoglobin_F
http://en.wikipedia.org/wiki/Hemoglobin#Types_in_humans
There's also the case of the fish antifreeze that evolved from non-protein-coding DNA:
"Scientists at the University of Illinois have discovered an antifreeze-protein gene in cod that has evolved from non-coding or 'junk' DNA."
http://www.sciencedaily.com/releases/2006/04/060404090831.htm
Science is not the search for "truth". It's the search for an explanation. Unfortunately, it has become the new religion, people simply believe what some scientist says as gospel and, as you identified, are then frustrated and irritated if it is found to be incomplete or utterly false.
That is not how science is to be treated. Science does not have all the answers. Science is the search for those answers, not the answer itself. Science is not about believing, it is about doubting. About offering a theory and offering ways to test that theory. Especially the latter part is often overlooked by people. A good theory offers an angle to falsify it. I may state that at the center of a black hole is cake. Just to make all the Portal players happy. And while we're at it, before the big bang there was a flat world carried by a turtle. You cannot falsify either theory. You cannot test them. So they have to be true. Right? False! Both are non-theories. They have zero scientific value. At least until we somehow find ways to test them.
So presenting any theory that offers no vector of testing is, scientifically, worthless. Unfortunately, that's not easy to convey to people. They want explanations. And science cannot offer them. Science is not about certain answers. It is about questioning theories.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Creationism is ridiculed because creationism is ridiculous. Such posts get modded up because people with mod points agree, whether on topic or not. It's not really worth a sociology paper or anything.
If you really want to defend creationism on /., I salute your bravery. If you are just trying to figure out why people do what they do, I wish you tremendous amounts of luck.