Word: cyclic
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Dates: during 1980-1989
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Whether these catastrophic impacts are random or cyclic remains to be seen. But if they occur at all, they could shake the foundations of evolutionary biology and call into question the current concept of natural selection. Should the Alvarez theory be correct, says Harvard Paleontologist Stephen Jay Gould, the importance of competition between species diminishes. If every so often a megablast opens up a broad array of ecological niches, then new creatures can flourish without having to crowd out the old. "If you ask the question, 'Why are we here?' " says Gould, "the answer is, 'Because the dinosaurs disappeared...
...controversy has engulfed not only astronomers, geologists, paleontologists and astrophysicists but even evolutionary biologists. If the cyclic theory is true, the biologists argue, many assumptions about the course of evolution on earth--and even the likelihood of finding complex life forms on other planets--will be overturned. Says Whitmire: "Just the possibility that life here has been controlled by an astronomical event is very far reaching...
Among the various astronomers who considered and promptly rejected the galactic carrousel notion was California's Muller, a scientist obsessed by periodicity. If a familiar cosmic mechanism could not account for the cyclic nature of extinctions, he decided, something completely different would have to do. During Christmas break in 1983, Muller and fellow Astronomers Marc Davis of Berkeley and Piet Hut of the Institute for Advanced Study in Princeton were brainstorming about stars and periodicity, when Muller noted that more than half the stars in the galaxy are thought to be binaries (pairs of stars that orbit a common center...
Postel said that the current outbreak occured primarily among young people might be attributed to the virus's cyclic pattern and that possibly the present generation of college age students grew up without immunity...
Tremblay unfolds the plot through gradual, cyclic self-revelation. On returning from a three month vacation in Europe to escape his family's problems. Serge has talks with his father and two aunts, his three elder sisters, and his lover, Nicole--and has talks, and has talks, and has talks. Wingrove's blocking is deft: Serge travels an a small circle around his bed, center stage, and is able to enter the houses and lives of each of his relatives with one single step towards their particular corner of the stage. His jerky, frantic movements contrast markedly with the immobility...