Can visiting a plant ruin an experiment?
By Susan Milius
Merely walking up to a plant and handling its leaves, which is routine for any researcher collecting data, may skew outcomes in studies of predators attacking plants, ecologists suggest.
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For two species out of six tested, the amount of leaf damage from insects differed significantly depending on whether researchers handled plants once a week or left them alone, report James Cahill Jr. of the University of Alberta in Edmonton and his colleagues.