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24 Dec 09

The Brain: What Is the Speed of Thought? | Mind & Brain | DISCOVER Magazine

  • Using a fast code helps speed up thought, but to a large extent the brain—like a telegraph network—really depends on efficient pathways. Impulses from the retinas, for instance, have to travel up the optic nerve to the thalamus, which relays the signals to the visual cortex in the back of the brain. Then they ripple forward to other brain centers, where we use the visual information to make decisions and take actions. One way to hasten that journey is to use fast wiring. In 1854 physicist William Thomson showed that the wider a telegraph wire, the faster its signal and the farther the signal could travel. That same principle applies to nerves. The fattest axons, such as Betz cells in the brain, are 200 times thicker than the thinnest ones.
  • Another way to speed up wires is to insulate them, and again the same goes for neurons.
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The Brain: What Is the Speed of Thought? | Mind & Brain | DISCOVER Magazine

  • Morse’s invention debuted just as researchers were starting to make sense of the nervous system, and telegraph wires were an inspiring model of how nerves might work. After all, nerves and telegraph wires were both long strands, and they both used electricity to transmit signals. Scientists knew that telegraph signals did not travel instantaneously; in one experiment, it took a set of dots and dashes a quarter of a second to travel 900 miles down a telegraph wire. Perhaps, the early brain investigators considered, it took time for nerves to send signals too. And perhaps we could even quantify that time.


  • Helmholtz’s results clashed with people’s gut instinct that they experienced the world as it happened, with no lag between sensation and awareness. “This is altogether a delusion,” German physiologist Emil Du Bois-Reymond declared in 1868. “It appears that ‘quick as thought’ is, after all, not so very quick.”

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23 Dec 09

20 Things You Didn't Know About... Nothing | DISCOVER Magazine

  • Black holes are not holes or voids; they are the exact opposite of nothing, being the densest concentration of mass known in the universe.
  • Any number divided by zero is . . . nothing, not even zero. The equation is mathematically impossible.
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20 Things You Didn't Know About... Time | Cosmology | DISCOVER Magazine

  • “Time is an illusion. Lunchtime doubly so,” joked Douglas Adams in The Hitchhiker’s Guide to the Galaxy. Scientists aren’t laughing, though. Some speculative new physics theories suggest that time emerges from a more fundamental—and timeless—reality.
  • The world’s most accurate clock, at the National Institute of Standards and Technology in Colorado, measures vibrations of a single atom of mercury. In a billion years it will not lose one second.
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19 Nov 09

Computer Based on Insights From The Brain Moves Closer to Reality

  • As the amount of digital data that we create continues to grow massively and the world becomes more instrumented and interconnected, there is a need for new kinds of computing systems - imbued with a new intelligence that can spot hard-to-find patterns in vastly varied kinds of data, both digital and sensory; analyze and integrate information real-time in a context-dependent way; and deal with the ambiguity found in complex, real-world environments.
  • Businesses will simultaneously need to monitor, prioritize, adapt and make rapid decisions based on ever-growing streams of critical data and information. A cognitive computer could quickly and accurately put together the disparate pieces of this complex puzzle, while taking into account context and previous experience, to help business decision makers come to a logical response.
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26 Oct 09

God, creation, science, religion: the conflicts - Telegraph

  • The argument rages to this day, although the weight of evidence is
    overwhelmingly in favour and very few biologists now question the basic idea
    of evolution.

  • In the early 19th century, a young girl called Mary Anning discovered a
    strange beast in the rock of the cliff-face in Lyme Regis, Dorset. It was a
    fossil ichthyosaur – a marine reptile that lived at the time of the
    dinosaurs.



    Other fossils were being found in their hundreds, in Britain, the United
    States and elsewhere. The fact that many of the creatures being found did
    not seem to exist on Earth led to problems with another of the Bible’s
    teaching: that God, through Noah, had saved all the animals of the world
    from the Flood.



    Taken together with the belief that God had given Adam “dominion over every
    living thing that moveth over the Earth”, it was widely believed that it was
    impossible for animals to go extinct. Anning’s discovery, and the arguments
    of Georges Cuvier and other scientists, made that position untenable.



    Another, greater problem for literal readings of the Bible was that if Noah
    had saved the dinosaurs, humanity must have coexisted with them

Modern man had sex with Neanderthals - Telegraph

  • "I'm sure that they had sex, but did it give offspring that contributed
    to us? We will be able to answer quite vigorously with the new [Neanderthal
    genome] sequence."
  • The phenomenon is already seen in modern animals such as horses and zebras,
    and lions and tigers, but resulting offspring have always been infertile.
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Immortality only 20 years away says scientist - Telegraph

  • Mr Kurzweil adds that although his claims may seem far-fetched, artificial
    pancreases and neural implants are already available.
  • I and many other scientists now believe
    that in around 20 years we will have the means to reprogramme our bodies'
    stone-age software so we can halt, then reverse, ageing. Then nanotechnology
    will let us live for ever.
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Science Explains: Why You Can’t Drink Red Wine With Fish | 80beats | Discover Magazine

  • Researchers found a correlation between the high iron content of red wine and a nasty, fishy aftertaste when the reds are sipped with seafood. In the experiment, tasters ate a bit of scallop, tasted some wine and evaluated the aftertaste on a scale of 1 to 4. The diners found the unpleasant aftertaste was more intense with wines that had a higher iron content, the researchers say
  • The iron content of a wine depends on the composition of the soil in which the grapes were grown, the dust on the berry, contamination during harvesting, transportation, and crushing, and the conditions during fermentation
22 Oct 09

Can animals be homosexual? | Science | The Guardian

  • "There's a video some researchers made of male bachelor gorillas engaging in fellatio, but it still hasn't been shown in the US," she says. "As far as I know, homosexual behaviour has been observed in all manner of animals, and if pleasure is driving it, why wouldn't they?"

Reduced genome works fine with 2000 chunks missing - 22 October 2009 - New Scientist

  • IT'S the blueprint for life, but not all of our genome is truly mission-critical. Now the first systematic search for non-essential regions of the human genome is providing an estimate of the "minimal genome" needed by a healthy human being, as well as clues to our evolutionary history.
  • Previous studies suggested it is possible to lead a full and healthy life without every single bit of the genome. "You don't need a complete genome to be a complete person," says Terry Vrijenhoek of the Radboud University Nijmegen Medical Centre in the Netherlands.
17 Oct 09

APOD: 2002 October 29 - A Lunar Rille

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apod.nasa.gov/ap021029.html - Preview

moon science astronomy

03 Oct 09

Ardi Fossil Discovery: New Human-Evolution Puzzle Piece - TIME

  • This tableau demolishes one aspect of what had been conventional evolutionary wisdom. Paleoanthropologists once thought that what got our ancestors walking on two legs in the first place was a change in climate that transformed African forest into savanna. In such an environment, goes the reasoning, upright-standing primates would have had the advantage over knuckle walkers because they could see over tall grasses to find food and avoid predators. The fact that Lucy's species sometimes lived in a more wooded environment began to undermine that theory. The fact that Ardi walked upright in a similar environment many hundreds of thousands of years earlier makes it clear that there must have been another reason.
  • That suggests that females mated preferentially with smaller-fanged males. In order for females to have had so much power, Lovejoy argues, Ar. ramidus must have developed a social system in which males were cooperative. Males probably helped females, and their own offspring, by foraging for and sharing food, for example — a change in behavior that could help explain why bipedality arose. Carrying food is difficult in the woods, after all, if you can't free up your forelimbs by walking erect.
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06 Jul 09

Party Animals: Early Human Culture Thrived in Crowds | LiveScience

  • as human population density increased so did the transmission of ideas and skills. The result: the emergence of more and more clever innovations.
  • The idea that demography is linked to modern human behavior has been around for decades,
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