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Erich Feldmeier

@biogarage #diversity Kim Hughes: The hottest guy guppies stand out in a crowd | Scienc... - 0 views

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    "Evolution likes to keep what works best. The rest falls by the wayside. In theory, this means that the most "fit" variations, say, a color that looks poisonous or one particularly attractive to the ladies, would become the most common. By this logic, the many colors of the guppy should have conformed to a single common pattern long ago. But they haven't. Instead, the male guppies continue to show not only bright colors but also a high diversity of colors. What keeps the variety going? The rare-male effect. Female guppies prefer the males that are rare, no matter what their color pattern actually is. This effect has been documented in the laboratory in guppies and in other species like fruit flies."
thinkahol *

Push-Button Logic on the Nanoscale - 0 views

thinkahol *

The Biology of Consciousness | WBUR and NPR - On Point with Tom Ashbrook - 0 views

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    "Renegade husband and wife philosophers Pat and Paul Churchland met forty years ago in a college Plato class. Their instincts as philosophers - then and now - run outside the philosophy mainstream. Where most philosophers looked to reason and logic to apprehend the human mind, the Churchlands looked - and look - to science. There is no independent "mind", these two practically say, just the human brain, three pounds of tissue and water, firing away behind all our emotions, beliefs, actions. Consciousness itself, they say, is straight biology, a machine. Once, that sounded esoteric. Now, it's on the frontline of debate over law, soul and life."
thinkahol *

YouTube - Sam Harris SALT - 2 views

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    December 9th, 02005 - Sam Harris"The View From The End Of The World"This is an audio only presentation. This talk took place in the Conference Center Golden Gate Room, San Francisco. Quote: With gentle demeanor and tight argument, Sam Harris carried an overflow audience into the core of one of the crucial issues of our time: What makes some religions lethal? How do they employ aggressive irrationality to justify threatening and controlling non-believers as well as believers? What should be our response? Harris began with Christianity. In the US, Christians use irrational arguments about a soul in the 150 cells of a 3-day old human embryo to block stem cell research that might alleviate the suffering of millions. In Africa, Catholic doctrine uses tortured logic to actively discourage the use of condoms in countries ravaged by AIDS. "This is genocidal stupidity," Harris said. Faith trumps rational argument. Common-sense ethical intuition is blinded by religious metaphysics. In the US, 22% of the population are CERTAIN that Jesus is coming back in the next 50 years, and another 22% think that it's likely. The good news of Christ's return, though, can only occur following desperately bad news. Mushroom clouds would be welcomed. "End time thinking," Harris said, "is fundamentally hostile to creating a sustainable future." Harris was particularly critical of religious moderates who give cover to the fundamentalists by not challenging them. The moderates say that all is justified because religion gives people meaning in their life. "But what would they say to a guy who believes there's a diamond the size of a refrigerator buried in his backyard? The guy digs out there every Sunday with his family, cherishing the meaningthe quest gives them." "I've read the books," Harris said. "God is not a moderate." The Bible gives strict instructions to kill various kinds of sinners, and their relatives, and on occasion their entire towns. Yet slavery is challenged nowhere in the New or
Janos Haits

Welcome to Less Wrong - 0 views

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    Less Wrong is an online community for people who want to apply the discovery of biases like the conjunction fallacy, the affect heuristic, and scope insensitivity in order to fix their own thinking.
Mike Chelen

RNA world easier to make : Nature News - 0 views

  • John Sutherland and his colleagues from the University of Manchester, UK
  • ribonucleotide
  • building block of RNA
  • ...29 more annotations...
  • Donna Blackmond, a chemist at Imperial College London.
  • strong evidence for the RNA world
  • 'RNA world' hypothesis, which suggests that life began when RNA, a polymer related to DNA that can duplicate itself and catalyse reactions
  • chemists had thought the subunits would probably assemble themselves first, then join to form a ribonucleotide
  • three distinct parts: a ribose sugar, a phosphate group and a base
  • RNA polymer is a string of ribonucleotides
  • efforts to connect ribose and base together have met with frustrating failure
  • researchers have now managed to synthesise
  • ribonucleotides
  • remedy is to avoid producing separate ribose-sugar and base subunits
  • makes a molecule whose scaffolding contains a bond that will
  • be the key ribose-base connection
  • atoms are then added around this skeleton
  • final connection is to add a phosphate group
  • influences the entire synthesis
  • acting as a catalyst, it guides small organic molecules into making the right connections
  • What we have ended up with is molecular choreography
  • objectors to the RNA-world theory say the RNA molecule as a whole is too complex to be created using early-Earth geochemistry
  • flaw is in the logic — that this experimental control by researchers in a modern laboratory could have been available on the early Earth
  • Robert Shapiro, a chemist at New York University
  • early-Earth scenarios
  • heating molecules in water, evaporating them and irradiating them with ultraviolet light
  • results showing that they can string nucleotides together
  • ultimate goal is to get a living system (RNA) emerging from a one-pot experiment
  • need to know what the constraints on the conditions are first
  • Shapiro sides with
  • another theory of life's origins
  • because RNA is too complex to emerge from small molecules, simpler metabolic processes
  • eventually catalysed the formation of RNA and DNA
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