Thursday, June 14, 2007

The Monster in the Closet...



The experiment, conducted by Sol Spiegelman of the University of Illinois, consisted of introducing the viral RNA into a medium containing the RNA's own replication enzyme, plus a supply of raw materials and some salts, and incubating the mixture. When Spiegelman did this, the system obligingly replicated the strands of naked RNA. Spiegelman then extracted some of the freshly synthesized RNA, put it in a separate nutrient solution, and let it multiply. He then decanted some of that RNA into yet another solution, and so on, in a series of steps.

The effect of allowing unrestricted replication was that the RNA that multiplied fastest won out, and got passed on to the "next generation" in the series. The decanting operation therefore replaced, in a highly accelerated way, the basic competition process of Darwinian evolution, acting directly on the RNA. In this respect it resembled an RNA world.

Spiegelman's results were spectacular. As anticipated, copying errors occurred during replication. Relieved of the responsibility of working for a living and the need to manufacture protein coats, the spoon-fed RNA strands began to slim down, shedding parts of the genome that were no longer required and merely proved to be an encumbrance. The RNA molecules that could replicate the fastest simply out-multiplied the competition. After seventy-four generations, what started out as an RNA strand with 4,500 nucleotide bases ended up as a dwarf genome with only 220 bases. This raw replicator with no frills attached could replicate very fast. It was dubbed Spiegelman's monster.


*Evolution at work in the laboratory.

In 1974, Manfred Eigen and his colleagues also experimented with a chemical broth containing Qb replication enzyme and salts, and an energized form of the four bases that make up the building blocks of RNA. They tried varying the quantity of viral RNA initially added to the mixture. As the amount of input RNA was progressively reduced, the experimenters found that, with little competition, it enjoyed untrammeled exponential growth. Even a single RNA molecule added to the broth was enough to trigger a population explosion.

But then something truly amazing was discovered. Replicating strands of RNA were still produced even when not a single molecule of viral RNA was added! To return to my architectural analogy, it was rather like throwing a pile of bricks into a giant mixer and producing, if not a house, then at least a garage. At first Eigen found the results hard to believe, and checked to see whether accidental contamination had occurred. Soon the experimenters convinced themselves that they were witnessing for the first time the spontaneous synthesis of RNA strands form their basic building blocks. Analysis revealed that under some experimental conditions the created RNA resembled Spiegelman's monster.

*Biogenesis in the lab? Well....lets be honest, its not quite biogenesis...its more pre-biogenesis. The RNA would have to form protein skins and develop into cellular organisms.....but its certainly a hint toward biogenesis.

Wednesday, June 13, 2007

More on Evolution....

The Canard: Random Mutation cannot produce complex 'finished' systems.

The Response: Mutations in evolution are not so much 'random' as indifferent, or undirected. There is no predictability or purpose to the mutation that, through natural selection, results in evolution...it just happens.


Jerry Coyne's explanation:

On the basis of much evidence, scientists have concluded that mutations occur randomly. The term "random" here has a specific meaning that is often misunderstood, even by biologists. What we mean is that mutations occur irrespective of whether they would be useful to the organism. Mutations are simply errors in DNA replication. Most of them are harmful or neutral, but a few of them can turn out to be useful. And there is no known biological mechanism for jacking up the probability that a mutation will meet the current adaptive needs of the organism. Bears adapting to snowy terrain will not enjoy a higher probability of getting mutations producing lighter coats than will bears inhabiting non-snowy terrain.


What we do not mean by "random" is that all genes are equally likely to mutate (some are more mutable than others) or that all mutations are equally likely (some types of DNA change are more common than others). It is more accurate, then, to call mutations "indifferent" rather than "random": the chance of a mutation happening is indifferent to whether it would be helpful or harmful. Evolution by selection, then, is a combination of two steps: a "random" (or indifferent) step--mutation--that generates a panoply of genetic variants, both good and bad (in our example, a variety of new coat colors); and then a deterministic step--natural selection--that orders this variation, keeping the good and winnowing the bad (the retention of light-color genes at the expense of dark-color ones).


So....if my imperfect understanding of the explanation is accurate, the following happens:

- Populations reproduce.

- Genetic mutation causes changes in offspring during embryonic formation.

- Offspring who 'chance' to have beneficial mutations that favour their survivability may survive to reproduce more than those with neutral or non-beneficial mutations.

- The population of 'beneficially mutated breeding subjects' is more likely to pass on a beneficial mutation to their offspring (along with other mutations).

- Over time the net accumulation of passed on beneficial traits may lead to a beneficial mutation being adapted by a species and becoming a 'common inheritance' of said species.

- Natural Selection combined with Beneficial Mutations may not result in increased complexity, but in fact may result in the reduction of certain complexities if those reductions amount to a net-positive or net-benefit for the species.


Note: I'm becoming quite a fan of Jerry Coyne.

Tuesday, June 12, 2007

Strange and Compelling



From: http://users.design.ucla.edu/~akoblin/

What happens when you amalgamate the flight paths over the US, colour coordinate them by airline, and then time-laps the flight paths? Serendipitous Beauty!

Thursday, June 7, 2007

The Succinct Definition of Evolution.

"There is only one going theory of evolution, and it is this: organisms evolved gradually over time and split into different species, and the main engine of evolutionary change was natural selection."

Jerry Coyne, Proff. Ecology and Evolution, University of Chicago.

Wednesday, June 6, 2007

Monday, June 4, 2007

Jennifer Aniston is Equivalent to HOW MANY chickens?

According to Weird Converter, Jen Aniston is equal to 24.9478363422 chickens.

This conversion tool has so many possibilities.

1 Giraffe's neck = 0.1197306539 the length of the world's longest snake.

Friday, June 1, 2007

The Pleasures of Altruism

http://www.washingtonpost.com/wp-dyn/content/article/2007/05/27/AR2007052701056.html

"Moll and Jordan Grafman, neuroscientists at the National Institutes of Health, had been scanning the brains of volunteers as they were asked to think about a scenario involving either donating a sum of money to charity or keeping it for themselves.

As Grafman read the e-mail, Moll came bursting in. The scientists stared at each other. Grafman was thinking, "Whoa -- wait a minute!"

The results were showing that when the volunteers placed the interests of others before their own, the generosity activated a primitive part of the brain that usually lights up in response to food or sex. Altruism, the experiment suggested, was not a superior moral faculty that suppresses basic selfish urges but rather was basic to the brain, hard-wired and pleasurable."

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So...there is some evidence that racial altruism or solidarity produces a pleasurable response in the brain of the typical human.
YET...we still see tribalism rampant in 21 century humanity. We understand that evolving a pleasurable altruism trait may be beneficial to humanity.

It feels good to be good to others, so if we're all good to each other, we'll all feel good together and that is a good thing.

But we compartmentalize, and segregate, and break down our species into smaller, easily sorted packages that we can conceptualize better.
Which brings up an interesting supposition. Do all these religious types who feel "all moral and warm" because of their faith, trigger this "pleasurable altruism" circuit in their brain through tribal solidarity of congregational fellowship?
Could this be part of the reason that so many people take comfort in tribal segregation - by joining a socieity that allows for maximum triggering of the "pleasurable altruism" circuit?
Sororities, Fraternities, Political Parties, Churches, Clubs, Gangs, Associations, Social Networking, Sporting Teams and Fan Associations - all may be humanity flailing around trying to maximize this triggering.