Researchers observing female Barbary macaques found that "middle hierarchy" monkeys experienced the most stress.

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Stephen Worthington of Barbary Coast Capital Management sees trouble brewing on the balance sheet of PacifiCare Health Systems.

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Researchers in Liverpool and Manchester observed female Barbary macaques for almost 600 hours, recording all incidences of social behaviour.

BBC: Monkey study helps explain stress of 'middle managers'