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Articles: Bird Memory; Cloned Emryos

Started by Robert Karl Sto · · Last activity · 1 post · 373 views

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General fitness, health and nutrition
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15 February 2004
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  1. Where'd I Put That? Maybe it takes a bird brain to find the car keys Susan Milius

    Should humanity get a little too full of itself and its intellectual prowess, there's always Clark's
    nutcracker to think about. This pale-gray bird with black wings and a long beak flits through
    woodlands in the West, collecting seeds during times of plenty and tucking them away for a hungry
    winter's day. During a year, each bird buries 22,000 to 33,000 seeds in up to 2,500 locations, and
    scientists estimate that the bird recovers two-thirds of them up to 13 months later.

    Just how seed cachers do this has fascinated biologists for decades. Scientific investigation of the
    topic has broadened and deepened in recent years. Cognitive scientists pose seed-storage puzzles to
    birds as a way of sorting out how their brains work and might resemble our own. Ecologists are
    looking for links between seed-caching powers and the perils of a species' environment.

    Robots no more

    Thirty years ago, biologists took a very different view of seed caching, reminisces one of the
    pioneers of the field, Russell Balda of Northern Arizona University in Flagstaff. Bird-watchers knew
    that certain species store food. These include some members of the family encompassing jays and
    crows, as well as that of chickadees and [censored]. Russian and Scandinavian scientists in particular had
    documented the remarkable industry and seed-recovery accuracy of birds surviving in far-northern
    regions. Yet, says Balda, speculation about how the birds manage these retrieval heroics centered on
    the simplest of mental powers.

    Scientists had trouble imagining that the birds have the brainpower to remember where seeds are.
    Instead, biologists typically speculated that the birds must follow a few simple rules, perhaps
    having favorite types of hiding places. The birds would hide seeds there; later, returning to the
    same preferred places, they would happen onto their caches.

    Biologists of that era tended to think of animals in general as "very robotic," says Balda. "In the
    early 1970s, the idea that animals were cognitive creatures was still in its infancy."

    Balda started studying pinyon jays and Clark's nutcrackers in the late 1960s. He noticed the
    nutcrackers heading high into the San Francisco Peaks in northern Arizona, and he organized his own
    flock of extreme bird trackers. To glimpse seed cachers at work, the researchers took advantage of
    most forms of transportation then available, from snowshoes to motorcycles. The project showed that
    nutcrackers carry their seeds as far as 25 kilometers to cache them, often hiding their supplies
    above the tree line. The shy birds were reluctant to cache when observed and often made fake
    deposits. "It was maddening," Balda says.

    The overwhelming logistical problems of observing the birds in the wild led Balda and his colleagues
    to begin to study caching in the laboratory in 1977. Their first experimental subject, a Eurasian
    nutcracker, obligingly buried seeds in a large sand floor while Balda watched from a corner. After
    each caching session, Balda dug up seeds and let the bird back into the aviary to search for its
    stores. "The bird caught on and refused to cache ever again," Balda says. "Now, we make sure our
    birds see us as providers of seeds, not robbers." The researchers don't let the birds know they're
    being watched while hiding seeds.

    Once the researchers got the kinks out of their laboratory system, the results began to undermine
    the idea that the birds just follow simple-minded rules. When Balda gave individual Clark's
    nutcrackers a second chance to cache seeds in the same sandy aviary floor, the birds often choose
    different hiding places.

    Also, when Balda removed all the seeds and smoothed any disturbances in the sand, the birds still
    searched in 60 percent to 90 percent of the correct locations in a half-hour recovery session.
    Moreover, the birds were able to find their treasures whether or not the researchers put landmarks
    such as cinder blocks, wall posters, and two-by-fours in the room. These findings ch allenged the
    idea that the birds were following some subtle sensory clue to the seeds themselves instead of
    relocating particular sites.

    In a further refinement of the experiments, Balda's research team built a floor that was 30 feet by
    50 feet, with 330 holes drilled in it to hold either Dixie cups of sand or plugs. This way the
    people, not the birds, determined the possible cache locations. Still, the birds maintained their
    high success rate in relocating their hiding places.

    Could it be that the birds were just poking around randomly until they happened on their caches? The
    rates of recovery, from half to virtually all the seeds cached, made that seem unlikely.

    Balda also tested one of his graduate students at caching. The student hid seeds and 30 days later
    found only about half as many caches as a bird typically did.

    Evidence grew that the remarkable birds indeed remembered spatial locations for their caches, says
    Balda, and bird minds began to seem more interesting than many scientists had expected.

    Moreover, scientific opinion about the minds of animals in general shifted during the 1970s and
    1980s, and biologists started looking at mental capability as another trait that natural selection
    shapes. Just as the fastest and biggest might best survive, so might the smartest.

    Caching research, says Balda, "played some role in changing how people viewed the animal mind."

    Read the rest at Science News sciencenews.orgbob8.asp

    Comment: Autistic Savants typically have this ability, but ordinary humans do not. It seems that
    some function of ordinary consciousness severely compromises this kind of memory ability. Some
    Autistic people respond to therapy and begin to approach normal social interaction. But as they do
    so, the amazing memory abilities start to diminish. The evolution of this form of consciousness must
    have occurred at a time when photographic memory was superfluous, or when only one or two members of
    a tribe needed to have it (story tellers, wise people, mystics and witch doctors etc).

    Tailoring Therapies: Cloned human embryo provides stem cells John Travis

    Scientists have for the first time used cloning to create human embryos that live long enough in a
    laboratory dish to have their stem cells harvested. The feat could set the stage for physicians to
    produce cells and tissues, tailored to a patient's genetic identity, that can treat a wide variety
    of human illnesses. The accomplishment also provides a road map for how to clone a person, an even
    more divisive undertaking.

    The new work, performed in South Korea, represents "a major advance in stem cell research . . . . It
    could help spur a medical revolution as important as antibiotics and vaccines," says Robert Lanza of
    Advanced Cell Technology (ACT), a company in Worcester, Mass., that's also investigating the
    promising stem cell strategy dubbed therapeutic cloning.

    "However, now that the methodology is publicly available," Lanza adds, "I think it is absolutely
    imperative that we pass laws worldwide to prevent the technology from being abused for reproductive-
    cloning purposes."

    While some fertility doctors and a religious cult have claimed success at creating a pregnancy via
    cloning, they've offered no convincing proof. In contrast, the South Korean research is being
    reported at the meeting of the American Association for the Advancement of Science in Seattle and
    will appear in an upcoming Science. "This is reality," says stem cell researcher John Gearhart of
    Johns Hopkins University. "Here is a bona fide, refereed journal saying that a human embryo has been
    cloned and a cell line derived from it."

    Read the rest at Science News sciencenews.orgfob1.asp

    Comment: I've sent a nice letter with samples of my DNA and polite request for a new brain. I
    patiently await...

    Posted by Robert Karl Stonjek.

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