Word: silkworms
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Dates: during 1950-1959
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...silkworm size or immense; at times invisible...
...nature's most baffling phenomena has been the extraordinary power of female moths to attract mates over long distances. In one experiment, a female emperor in a gauze cage collected 127 males of her species in seven hours; male Chinese silkworm moths have been known to home in on intended mates from as far away as seven miles. Since a female under a bell jar will stir nothing in males on the outside only inches away, biologists have concluded that the secret of her charm must be an odor-from a substance so strong that a few molecules send...
...massive experiment conducted by Adolf Butenandt, 56, who was co-winner of the 1939 Nobel Prize in Chemistry (for isolating the male sex hormone, androsterone), a research team at Munich's Max Planck Institute for Biochemistry imported 1,000,000 silkworm cocoons from Italy and Japan, opened them up with razor blades, separated the pupae of 310,000 females from the males. What followed, in the words of one researcher, was "a mass slaughter, and not for the fainthearted." Each tiny pupa was disemboweled, the scent glands carefully cut out. Male moths served as lab assistants: when they were...
Biologists guessed a generation ago that the metamorphosis of insects (changing from larvae to pupae and from pupae to adults) is probably controlled by a chemical hormone. Three years ago Dr. Williams extracted an oil from the abdomens of silkworm moths, injected it into silkworm pupae. It stopped their normal development. The pupae never became adult moths, instead developed into a second kind of pupa. Smaller doses brought forth monstrosities with mingled patches of adult and juvenile tissue. Williams concluded that the oil contained a "juvenile hormone...
...discovery, other biologists ransacked nature looking for the presence of the juvenile hormone in other species. Last year Drs. Lawrence I. Gilbert and Howard A. Schneiderman of Cornell University extracted a substance from the cortex of the adrenal glands of cattle. They found it had the same effect on silkworm pupae as the moth hormone. For the first time a hormone extracted from vertebrates was shown to influence the growth of invertebrate insects...