Re: Study Shows How Insects Lost Extra, Clumsy Legs, etc

From: Stephen E. Jones (sejones@iinet.net.au)
Date: Tue May 02 2000 - 17:40:15 EDT

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    Reflectorites

    Here are three Yahoo stories. The first is about antibiotic resistance in
    bacteria being due to two genes for cell membrane repair which are
    naturally selected.

    The second is about the death of a `talking' gorilla named Michael who was
    apparently an exponent of (modern?) art! Apparently Michael did not have
    any memorable sayings to report, so the article mentions that another
    gorilla named Koko "took to the Internet in what was billed as the first
    `interspecies' chat, relaying pithy comments such as `I like drinks' through a
    human interpreter to tens of thousands of online participants." I presume if
    the interpreter was hungry Koko would have said "I like hamburgers"? :-)

    The third story is perhaps the most interesting. It claims that by suppressing
    genes in beetle larvae, they grew extra legs. It seems to be saying that
    insects arose from centipedes by this mechanism. But that would seem to
    be a *loss* of genetic information? This would mean that all the
    information for the making of insects was already `front loaded' into
    centipedes? But as my tagline quote says, "Aviation engineers look with
    envy on...insects" because their wings are far more efficient than aircraft
    wings. Insect wings "can exploit an intriguing loophole in the laws of
    aerodynamics." So, the master genes which built centipedes bodies already
    had encoded in them a plan for making insect wings in the distant future
    which "exploit an intriguing loophole in the laws of aerodynamics." If this
    is the case then this would be evidence for intelligent design by forward
    planning, or as Paley put it "prospective contrivances":

    "CHAPTER XIV. PROSPECTIVE CONTRIVANCES. I CAN hardly
    imagine to myself a mere distinguishing mark, and, consequently, a more
    certain proof of design, than *preparation*, i.e. the providing of things
    beforehand, which are not to be used until a considerable time afterwards
    for this implies a contemplation of the future, which belongs only to
    intelligence." (Paley W., "Natural Theology," 1972, reprint, p.179.
    Emphasis in original.)

    Steve

    ================================================
    http://dailynews.yahoo.com/h/nm/20000424/sc/health_resistance_1.html

    [...]

    Yahoo

    Monday April 24 5:04 PM ET Study Points to Drug Resistance Genes in
    Bacteria WASHINGTON (Reuters) - Two genes help bacteria outwit
    penicillin and switching off those genes makes the bugs completely
    vulnerable to the antibiotic, researchers said on Monday.

    Those findings could help scientists develop better infection-fighting drugs,
    they reported in the Proceedings of the National Academy of Sciences.

    More than 90 percent of all strains of Staphylococcus aureus, the most
    common cause of infections, now resist penicillin, U.S. government
    researchers say.

    The related S. pneumoniae is estimated to cause at least 6,000 cases of
    meningitis, 50,000 cases of blood infections, a half million cases of
    pneumonia and several million childhood ear infections in the United States
    every year. Globally, staph infections kill a million people every year.

    [...]

    New antibiotics are being developed, but because bacteria evolve so
    quickly, resistance is almost certain at some point. Therefore, scientists
    have to keep adding to the arsenal.

    Alexander Tomasz and colleagues at Rockefeller University in New York
    have spent two decades studying how staph and other bacteria develop
    their resistance to penicillin.

    They found that bacteria can rebuild the cell wall breached by penicillin,
    and homed in on the two genes, called MurM and MurN, involved in this
    process.

    Writing in the Proceedings of the National Academy of Sciences, they said
    the genes are responsible for producing molecules called branched
    muropeptides, which are important to the cell wall structure.

    "We have now identified two genes that are responsible for making these
    branched muropeptides, and we have shown for the first time that by
    inactivating these genes we can restore penicillin's potency," Tomasz said
    in a statement.

    "This opens the door to the development of new drugs that would act
    synergistically with penicillin by blocking the production of the branched
    peptides."

    E-mail this story

    [...]

    Copyright (c) 2000 Reuters Limited. All rights reserved.

    [...]

    ================================================

    ================================================
    http://dailynews.yahoo.com/h/nm/20000420/sc/life_gorilla_1.html

    Yahoo!

    [...]

    Thursday April 20 2:55 PM ET One of Two 'Talking' Gorillas Dies in
    California

    Reuters Photo

    WOODSIDE, Calif. (Reuters) - Michael, one of two lowland gorillas said
    to have mastered basic American Sign Language, has died at the California
    institute which had studied him since 1976. He was 27.

    Officials at the Gorilla Foundation in Woodside, just south of San
    Francisco, said Michael collapsed in his outdoor play area on Wednesday
    and, despite efforts to resuscitate him, died shortly afterward.

    Gorillas are susceptible to heart disease, although it was not clear on
    Thursday if this is what killed Michael.

    Dr. Francine Patterson, who cared for and taught Michael since he was
    brought to California from Cameroon, West Africa in 1976, said he
    expressed his artistic spirit through language, music and art.

    "He has been an inspiration to us all," Patterson said in a news release
    announcing the gorilla's death.

    "He had a great facility with gestural communication and was a talented
    artist. His work has been displayed in galleries around the country. He was
    our group's silverback (dominant male) and we will miss his strong
    presence a great deal."

    [...]

    Michael, who was said to have mastered more than 500 signs in American
    Sign Language, is survived by one other "talking" gorilla, 29-year-old
    Koko, and her male companion, Ndume, 18.

    Koko and Michael achieved worldwide fame with their prowess in
    American Sign Language, and were said by their human keepers to
    understand some spoken English as well.

    While some scientists remained doubtful about the claim, the two "talking"
    lowland gorillas nevertheless became important ambassadors for their
    species, which is threatened by logging and poaching in their native habitats
    in central Africa. Their cousins, the mountain gorillas, number now fewer
    than 500 in the wild.

    In 1997, a San Francisco gallery exhibited paintings by both gorillas, saying
    the acrylic-on-canvas work offered "an unprecedented glimpse of the joys,
    frustrations and desires that they encounter in daily life."

    In 1998, Koko took to the Internet in what was billed as the first
    "interspecies" chat, relaying pithy comments such as "I like drinks" through
    a human interpreter to tens of thousands of online participants.

    E-mail this story

    [...]

    Copyright (c) 2000 Reuters Limited. All rights reserved.

    [...]

    ================================================

    ================================================
    http://dailynews.yahoo.com/h/nm/20000424/sc/science_legs_1.html

    Yahoo!

    [...]

    Monday April 24 5:01 PM ET Study Shows How Insects Lost Extra,
    Clumsy Legs By Maggie Fox, Health and Science Correspondent

    WASHINGTON (Reuters) - A couple of genes helped insects evolve from
    leggy millipedes and boring worms into flies, beetles and fleas and probably
    helped them become among the most numerous creatures on the Earth,
    researchers said on Monday.

    When they suppressed the two genes in beetle larvae, the grubs grew extra
    legs, although they did not work well, Randy Bennett and colleagues at
    Brigham Young University in Provo, Utah reported.

    "We got legs everywhere," Bennett said.

    [...]

    The findings, published in the Proceedings of the National Academy of
    Sciences, shed light on how so many different animals developed and also
    have implications for scientists studying human genetics -- even gene
    therapy, Bennett said.

    "They were central characters in the specialization of the insect body plan.
    These two were involved in making the abdomen, the hind end of an insect,
    special and different from the middle," Bennett said in a telephone
    interview.

    "We do see that there are a lot of similar genes involved in most animals,
    and we are trying to see how they use these to make different body types."

    Hundreds of millions of years ago, there were far fewer kinds of creatures
    around, Bennett said. Only when they developed new genes could things
    get interesting.

    "Building a genetic toolkit that allows different animals to diversify, until
    you have a certain number of tools -- genes -- in your toolbox, animals
    could not do much but be sponges and jellyfish and flatworms," said
    Bennett, a developmental biologist.

    Once they got a few interesting genes, "then they could have fun."

    Insects, which include flies, beetles, fleas and bees, have six legs on the
    middle region or thorax of their bodies.

    But fossils show that modern insects descended from animals that looked
    more like centipedes, with many legs and sometimes multiple wings along
    their bodies.

    Bennett said the two genes, known as Ubx and abd-A, helped insects
    develop the three-regioned body plan that is so familiar -- head, thorax and
    abdomen. The thorax is the only region with legs and wings on it.

    The genes belong to a family of genes, known as hox genes, that are
    known to encode for master body plans.

    They also play a role in humans.

    "They don't do exactly the same thing," Bennett said. "They do help make
    different regions of the body different from other regions. So if you look
    down the spinal column, you see that cervical vertebrae are different from
    the thoracic vertebrae."

    He said his experiment would not create monstrous babies if tried on
    human beings. "If we took (the genes) out of humans, we would not get
    legs coming out," he said.

    But the findings have implications for studying human genetics, because the
    study shows that genes have complex relationships and that changing one
    gene can alter the functions of many others.

    And Bennett said the study helps illustrate how animals developed
    evolutionary advantages. Winged insects have a clear advantage over
    millipedes, he said.

    "When you pick up a rock, when you look under a log, you find centipedes
    or millipedes," Bennett said in a statement.

    "You don't see them just everywhere, whereas insects we do see just
    everywhere. So there seems to be an advantage to having wings and six
    legs."

    Photos of the insects can be found on the Internet at
    http://www.byu.edu/news/releases/Apr/beetles/photos.html.

    [...]

    Copyright (c) 2000 Reuters Limited. All rights reserved.

    [...]
    ================================================

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    "Aviation engineers look wide envy on birds and especially insects. Their
    flapping wings lift and propel them far more efficiently than the fixed wings
    of aircraft. One reason is their ability to exploit the subtleties of stalling.
    If the angle of attack of a wing is increased, it ultimately stalls, with sudden
    disastrous loss of lift. No fixed-wing aircraft dare risk stalling But an insect
    with oscillating wings can exploit an intriguing loophole in the laws of
    aerodynamics. Accelerated at a high angle of attack into the stalling
    regime, a wing takes a short while to stall. And until it does, it generates
    enormous lift. By speeding into stall and out again at each flap, an insect
    wing develops amazingly high average lift. (Jones D., "The insect plane,"
    Nature, Vol. 400, 5 August 1999, p.513).
    Stephen E. Jones | sejones@iinet.net.au | http://www.iinet.net.au/~sejones
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