Word: protozoa
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...main problem is filling up the reservoir,"he said. "Possibly, depending on what they'retrapping in the sludge, viruses and protozoa couldalso become concentrated [in the redepositedwaste...
...however, is a more recent invention. Biologist Lynn Margulis of the University of Massachusetts at Amherst believes the evolutionary roots of egg and sperm cells can be traced back to a group of organisms known as protists that first appeared some 1.5 billion years ago. (Modern examples include protozoa, giant kelp and malaria parasites.) During periods of starvation, Margulis conjectures, one protist was driven to devour another. Sometimes this cannibalistic meal was incompletely digested, and the nuclei of prey and predator fused. By joining forces, the fused cells were better able to survive adversity, and because they survived, their penchant...
From this vantage point, human sexuality seems little more than a wondrous accident, born of a kind of original sin among protozoa. Most population biologists, however, believe sex was maintained over evolutionary time because it somehow enhanced survival. The mixing and matching of parental genes, they argue, provide organisms with a novel mechanism for generating genetically different offspring, thereby increasing the odds that their progeny could exploit new niches in a changing environment and, by virtue of their diversity, have a better chance of surviving the assaults of bacteria and other tiny germs that rapidly evolve tricks for eluding their...
...Rearrangements in Protozoa: Sex and the Single Cell: Kathleen M. Karrer, Gerstenzang Building, Brandeis, Waltham, Saturday...
...census taking can be hazardous. The employees counting poison darts and hedgehogs required thick cloth gloves; those cataloguing protozoa developed eyestrain after weeks of staring intently into microscopes; those working with uranium samples had to wear special devices to monitor levels of radiation; and those tallying mammals preserved in alcohol experienced queasy stomachs. "It doesn't smell like Chivas Regal in those collections," sniffed one researcher...